Fixed issue #378 - Don't show empty floating containers on startup

This fixes a crash which could occur when restoring the state of a floating container to a non-floating container.

This was because `ads::CDockContainerWidget::RestoreState()` will unconditionally assume this is floating if the XML has the `Floating` boolean set, and will dereference `floatingWidget()`. If this isn't floating, `floatingWidget()` will return `nullptr`, leading to a crash when it's subsequently used.

Fixes #379.

.github/workflows/linux-builds.yml

@@ -6,7 +6,7 @@ jobs:
   build:
     strategy:
       matrix:
-        os: [ubuntu-latest, ubuntu-18.04, ubuntu-16.04]
+        os: [ubuntu-latest, ubuntu-20.04, ubuntu-18.04]
 
     runs-on: ${{ matrix.os }}
     
@@ -16,7 +16,7 @@ jobs:
       run: |
         sudo apt-get update --fix-missing
         sudo apt-get install qt5-default
-        sudo apt-get install libqt5x11extras5-dev
+        sudo apt-get install qtbase5-private-dev
     - name: qmake
       run: qmake
     - name: make

.gitignore

@@ -383,3 +383,4 @@ FodyWeavers.xsd
 / build
 /Settings.ini
 .vscode/settings.json
+/.settings

.settings/language.settings.xml

@@ -1,12 +0,0 @@
-<?xml version="1.0" encoding="UTF-8" standalone="no"?>
-<project>
-	<configuration id="cdt.managedbuild.toolchain.gnu.mingw.base.1119687795" name="Default">
-		<extension point="org.eclipse.cdt.core.LanguageSettingsProvider">
-			<provider-reference id="org.eclipse.cdt.managedbuilder.core.GCCBuiltinSpecsDetectorMinGW" ref="shared-provider"/>
-			<provider copy-of="extension" id="org.eclipse.cdt.ui.UserLanguageSettingsProvider"/>
-			<provider-reference id="org.eclipse.cdt.core.ReferencedProjectsLanguageSettingsProvider" ref="shared-provider"/>
-			<provider class="org.eclipse.cdt.managedbuilder.language.settings.providers.GCCBuildCommandParser" id="org.eclipse.cdt.managedbuilder.core.GCCBuildCommandParser" keep-relative-paths="false" name="CDT GCC Build Output Parser" parameter="(g?cc)|([gc]\+\+)|(clang)" prefer-non-shared="true"/>
-			<provider-reference id="org.eclipse.cdt.managedbuilder.core.MBSLanguageSettingsProvider" ref="shared-provider"/>
-		</extension>
-	</configuration>
-</project>

.travis.yml

@@ -18,7 +18,6 @@ matrix:
         packages:
         - qt55base
         - qt55tools
-        - qt55x11extras
         - gcc-9
         - g++-9
     script:
@@ -45,7 +44,6 @@ matrix:
         packages:
         - qt514base
         - qt514tools
-        - qt514x11extras
         - gcc-9
         - g++-9
         - libc6-i386
@@ -67,7 +65,7 @@ matrix:
     services:
         - xvfb
     compiler: gcc
-    addons:
+    addons:  
       apt:
         sources:
         - ubuntu-toolchain-r-test
@@ -76,7 +74,6 @@ matrix:
         packages:
         - qt514base
         - qt514tools
-        - qt514x11extras
         - gcc-9
         - g++-9
         - libc6-i386
@@ -107,7 +104,6 @@ matrix:
         packages:
         - qt514base
         - qt514tools
-        - qt514x11extras
         - gcc-9
         - g++-9
         - libc6-i386
@@ -144,7 +140,6 @@ matrix:
         packages:
         - qt514base
         - qt514tools
-        - qt514x11extras
         - gcc-9
         - g++-9
         - libc6-i386

README.md

@@ -1,6 +1,6 @@
 # Advanced Docking System for Qt
 
-[![Build Status](https://travis-ci.org/githubuser0xFFFF/Qt-Advanced-Docking-System.svg?branch=master)](https://travis-ci.org/githubuser0xFFFF/Qt-Advanced-Docking-System)
+[![Build status](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/workflows/linux-builds/badge.svg)](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/actions?query=workflow%3Alinux-builds)
 [![Build status](https://ci.appveyor.com/api/projects/status/qcfb3cy932jw9mpy/branch/master?svg=true)](https://ci.appveyor.com/project/githubuser0xFFFF/qt-advanced-docking-system/branch/master)
 [![License: LGPL v2.1](https://img.shields.io/badge/License-LGPL%20v2.1-blue.svg)](gnu-lgpl-v2.1.md)
 
@@ -15,7 +15,34 @@ integrated development environments (IDEs) such as Visual Studio.
 
 ## New and Noteworthy
 
-The [release 3.5.0](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/releases/tag/3.5.0)
+The [release 3.8](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/releases/tag/3.8.0)
+adds the following features:
+
+- option to close tabs with the middle mouse button
+- `DeleteContentOnClose` flag for dynamic deletion and creation of dock widget
+  content
+
+The [release 3.7](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/releases/tag/3.7.0)
+adds the following features:
+
+- support for **Qt6.**
+- support for [empty dock area](doc/user-guide.md#empty-dock-area)
+
+The [release 3.6](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/releases/tag/3.6.0)
+adds some nice new features:
+
+- support for [central widget](doc/user-guide.md#central-widget) concept
+
+![Central Widget](doc/central_widget.gif)
+
+- support for [native floating widgets](doc/user-guide.md#floatingcontainerforcenativetitlebar-linux-only) on Linux
+
+![FloatingContainerForceNativeTitleBar true](doc/cfg_flag_FloatingContainerForceNativeTitleBar_true.png)
+
+Both features are contributions from ADS users. Read the [documentation](doc/user-guide.md)
+to learn more about both new features.
+
+The [release 3.5](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/releases/tag/3.5.0)
 adds the new [focus highlighting](doc/user-guide.md#focushighlighting) feature.
 This optional feature enables highlighting of the focused dock widget like you
 know it from Visual Studio.
@@ -42,6 +69,7 @@ know it from Visual Studio.
   - [Supports deletion of dynamically created dock widgets](#supports-deletion-of-dynamically-created-dock-widgets)
   - [Python PyQt5 Bindings](#python-pyqt5-bindings)
 - [Tested Compatible Environments](#tested-compatible-environments)
+  - [Supported Qt Versions](#supported-qt-versions)
   - [Windows](#windows)
   - [macOS](#macos)
   - [Linux](#linux)
@@ -60,6 +88,8 @@ know it from Visual Studio.
   - [ezEditor](#ezeditor)
   - [D-Tect X](#d-tect-x)
   - [HiveWE](#hivewe)
+  - [Ramses Composer](#ramses-composer)
+  - [Plot Juggler](#plot-juggler)
 
 ### Docking everywhere - no central widget
 
@@ -67,8 +97,8 @@ There is no central widget like in the Qt docking system. You can dock on every
 border of the main window or you can dock into each dock area - so you are
 free to dock almost everywhere.
 
-![Dropping widgets](doc/preview-dragndrop.png)\
-\
+![Dropping widgets](doc/preview-dragndrop.png)
+
 ![Dropping widgets](doc/preview-dragndrop_dark.png)
 
 ### Docking inside floating windows
@@ -76,8 +106,8 @@ free to dock almost everywhere.
 There is no difference between the main window and a floating window. Docking
 into floating windows is supported.
 
-![Docking inside floating windows](doc/floating-widget-dragndrop.png)\
-\
+![Docking inside floating windows](doc/floating-widget-dragndrop.png)
+
 ![Docking inside floating windows](doc/floating-widget-dragndrop_dark.png)
 
 ### Grouped dragging
@@ -86,8 +116,8 @@ When dragging the titlebar of a dock, all the tabs that are tabbed with it are
 going to be dragged. So you can move complete groups of tabbed widgets into
 a floating widget or from one dock area to another one.
 
-![Grouped dragging](doc/grouped-dragging.gif)\
-\
+![Grouped dragging](doc/grouped-dragging.gif)
+
 ![Grouped dragging](doc/grouped-dragging_dark.png)
 
 ### Perspectives for fast switching of the complete main window layout
@@ -98,13 +128,13 @@ perspective to make your own custom perspective. Later you can simply
 select a perspective from the perspective list to quickly switch the complete 
 main window layout.
 
-![Perspective](doc/perspectives.gif)\
-\
+![Perspective](doc/perspectives.gif)
+
 ![Perspective](doc/perspectives_dark.png)
 
 ### Opaque and non-opaque splitter resizing
 
-The advanced docking system uses standard QSplitters as resize separators and thus supports opaque and non-opaque resizing functionality of QSplitter. In some rare cases, for very complex widgets or on slow machines resizing via separator on the fly may cause flicking and glaring of rendered content inside a widget. The global dock manager flag `OpaqueSplitterResize` configures the resizing behaviour of the splitters. If this flag is set, then widgets are resized dynamically (opaquely) while interactively moving the splitters. 
+The advanced docking system uses standard QSplitters as resize separators and thus supports opaque and non-opaque resizing functionality of QSplitter. In some rare cases, for very complex widgets or on slow machines resizing via separator on the fly may cause flicking and glaring of rendered content inside a widget. The global dock manager flag `OpaqueSplitterResize` configures the resizing behaviour of the splitters. If this flag is set, then widgets are resized dynamically (opaquely) while interactively moving the splitters.
 
 ![Opaque resizing](doc/opaque_resizing.gif)
 
@@ -157,6 +187,10 @@ Latest working version: [3.5.2](https://github.com/githubuser0xFFFF/Qt-Advanced-
 
 ## Tested Compatible Environments
 
+### Supported Qt Versions
+
+The library supports **Qt5** and **Qt6**.
+
 ### Windows
 
 Windows 10 [![Build status](https://ci.appveyor.com/api/projects/status/qcfb3cy932jw9mpy/branch/master?svg=true)](https://ci.appveyor.com/project/githubuser0xFFFF/qt-advanced-docking-system/branch/master)
@@ -173,20 +207,34 @@ The application can be compiled for macOS. A user reported, that the library wor
 
 ### Linux
 
-Ubuntu [![Build Status](https://travis-ci.org/githubuser0xFFFF/Qt-Advanced-Docking-System.svg?branch=master)](https://travis-ci.org/githubuser0xFFFF/Qt-Advanced-Docking-System)
+[![Build Status](https://travis-ci.org/githubuser0xFFFF/Qt-Advanced-Docking-System.svg?branch=master)](https://travis-ci.org/githubuser0xFFFF/Qt-Advanced-Docking-System)
 [![Build status](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/workflows/linux-builds/badge.svg)](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/actions?query=workflow%3Alinux-builds)
 
-The application can be compiled for Linux and has been developed and tested with **Kubuntu 18.04** and **Kubuntu 19.10**.
+Unfortunately, there is no such thing as a Linux operating system. Linux is a heterogeneous environment with a variety of different distributions. So it is not possible to support "Linux" like this is possible for Windows. It is only possible to support and test a small subset of Linux distributions. The library can be compiled for and has been developed and tested with the following Linux distributions:
 
+- **Kubuntu 18.04 and 19.10**
+- **Ubuntu 18.04, 19.10 and 20.04**
+
+There are some requirements for the Linux distribution that have to be met:
+
+- an X server that supports ARGB visuals and a compositing window manager. This is required to display the translucent dock overlays ([https://doc.qt.io/qt-5/qwidget.html#creating-translucent-windows](https://doc.qt.io/qt-5/qwidget.html#creating-translucent-windows)). If your Linux distribution does not support this, or if you disable this feature, you will very likely see issue [#95](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/issues/95).
+- Wayland is not properly supported by Qt yet. If you use Wayland, then you should set the session type to x11: `XDG_SESSION_TYPE=x11 ./AdvancedDockingSystemDemo`. You will find more details about this in issue [#288](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/issues/288).
+
+Screenshot Kubuntu:
 ![Advanced Docking on Kubuntu Linux](doc/linux_kubuntu_1804.png)
 
-and with **Ubuntu 19.10**
-
+Screenshot Ubuntu:
 ![Advanced Docking on Ubuntu Linux](doc/linux_ubuntu_1910.png)
 
 ## Build
 
-Open the `ads.pro` with QtCreator and start the build, that's it.
+The Linux build requires private header files. Make sure that they are installed:
+
+```bash
+sudo apt install qtbase5-private-dev
+```
+
+Open the `ads.pro` file with QtCreator and start the build, that's it.
 You can run the demo project and test it yourself.
 
 ## Getting started / Example
@@ -321,7 +369,7 @@ Taken from the [Qt Blog](https://www.qt.io/blog/qt-design-studio-1.5-beta-releas
 
 > The most obvious change in [Qt Design Studio 1.5](https://www.qt.io/blog/qt-design-studio-1.5-beta-released) is the integration of dock widgets using the Qt Advanced Docking System. This allows the user to fully customize the workspace and also to undock any view into its own top level window. This especially improves the usability when using multiple screens.
 
-![Qt Design Studio](doc/showcase_qt_design_studio.png)
+[![Qt Design Studio](doc/showcase_qt_design_studio_video.png)](https://youtu.be/za9KBWcFXEw?t=84)
 
 ### [QmixElements](https://www.cetoni.com/products/qmixelements/)
 
@@ -357,4 +405,39 @@ of the open editor windows.
 
 [learn more...](https://github.com/stijnherfst/HiveWE)
 
-![HiveWE](doc/showcase_hivewe.png)
+![HiveWE](doc/showcase_hivewe.png)
+
+### [Ramses Composer](https://github.com/GENIVI/ramses-composer)
+
+Ramses Composer is the authoring tool for the open source [RAMSES](https://github.com/GENIVI/ramses)
+rendering ecosystem.
+
+Ramses is a low-level rendering engine which is optimized for embedded hardware
+mobile devices, automotive ECUs, IoT electronics. Ramses was initially developed
+at the BMW Group and open-sourced in 2018 as part of a collaboration initiative
+with the Genivi Alliance. It is an important part of the BMW infotainment cluster
+and digital portfolio.
+
+[learn more...](https://github.com/GENIVI/ramses-composer)
+
+![RamsesComposer](doc/showcase_ramses_composer.png)
+
+### [Plot Juggler](https://github.com/facontidavide/PlotJuggler)
+
+PlotJuggler is a fast, powerful and intuitive tool to visualize time series.
+It makes it easy to visualize data but also to analyze it. You can manipulate
+your time series using a simple and extendable Transform Editor. Some of the
+highlights are:
+
+- Simple Drag & Drop user interface.
+- Load data from file.
+- Connect to live streaming of data.
+- Save the visualization layout and configurations to re-use them later.
+- Fast OpenGL visualization.
+- Can handle thousands of timeseries and millions of data points.
+- Transform your data using a simple editor: derivative, moving average, integral, etc…
+- PlotJuggler can be easily extended using plugins.
+
+[read more...](https://github.com/facontidavide/PlotJuggler)
+
+[![Plot Juggler](doc/showcase_plot_juggler.png)](https://vimeo.com/480588113#t=46s)

ads.pri

@@ -0,0 +1,25 @@
+
+CONFIG(debug, debug|release){
+    win32 {
+    	versionAtLeast(QT_VERSION, 5.15.0) {
+    		LIBS += -lqtadvanceddocking
+    	}
+    	else {
+    		LIBS += -lqtadvanceddockingd
+    	}
+    }
+    else:mac {
+        LIBS += -lqtadvanceddocking_debug
+    }
+    else {
+        LIBS += -lqtadvanceddocking
+    }
+}
+else{
+    LIBS += -lqtadvanceddocking
+}
+
+
+unix:!macx {
+    LIBS += -lxcb
+}

adsConfig.cmake

@@ -2,5 +2,4 @@ include(CMakeFindDependencyMacro)
 find_dependency(Qt5Core ${REQUIRED_QT_VERSION} REQUIRED)
 find_dependency(Qt5Gui ${REQUIRED_QT_VERSION} REQUIRED)
 find_dependency(Qt5Widgets ${REQUIRED_QT_VERSION} REQUIRED)
-find_dependency(Qt5X11Extras ${REQUIRED_QT_VERSION} REQUIRED)
 include("${CMAKE_CURRENT_LIST_DIR}/adsTargets.cmake")

demo/CMakeLists.txt

@@ -1,9 +1,10 @@
 cmake_minimum_required(VERSION 3.5)
 project(ads_demo VERSION ${VERSION_SHORT}) 
 
-find_package(Qt5 5.5 COMPONENTS Core Gui Widgets REQUIRED)
-if(WIN32)
-    find_package(Qt5 5.5 COMPONENTS AxContainer REQUIRED)
+find_package(QT NAMES Qt6 Qt5 COMPONENTS Core REQUIRED)
+find_package(Qt${QT_VERSION_MAJOR} 5.5 COMPONENTS Core Gui Widgets REQUIRED)
+if(WIN32 AND QT_VERSION_MAJOR LESS 6)
+    find_package(Qt${QT_VERSION_MAJOR} COMPONENTS AxContainer REQUIRED)
 endif()
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
 set(ads_demo_SRCS
@@ -16,9 +17,11 @@ set(ads_demo_SRCS
 )
 add_executable(AdvancedDockingSystemDemo WIN32 ${ads_demo_SRCS})
 target_include_directories(AdvancedDockingSystemDemo PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/../src")
-target_link_libraries(AdvancedDockingSystemDemo PUBLIC Qt5::Core Qt5::Gui Qt5::Widgets)
-if(WIN32)
-    target_link_libraries(AdvancedDockingSystemDemo PUBLIC Qt5::AxContainer)
+target_link_libraries(AdvancedDockingSystemDemo PUBLIC Qt${QT_VERSION_MAJOR}::Core 
+                                                       Qt${QT_VERSION_MAJOR}::Gui 
+                                                       Qt${QT_VERSION_MAJOR}::Widgets)
+if(WIN32 AND QT_VERSION_MAJOR LESS 6)
+    target_link_libraries(AdvancedDockingSystemDemo PUBLIC Qt${QT_VERSION_MAJOR}::AxContainer)
 endif()
 target_link_libraries(AdvancedDockingSystemDemo PRIVATE qtadvanceddocking)
 set_target_properties(AdvancedDockingSystemDemo PROPERTIES 

demo/MainWindow.cpp

@@ -58,11 +58,15 @@
 #include <QMessageBox>
 #include <QMenu>
 #include <QToolButton>
+#include <QToolBar>
+#include <QPointer>
 
 
 #ifdef Q_OS_WIN
+#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
 #include <QAxWidget>
 #endif
+#endif
 
 #include <QMap>
 #include <QElapsedTimer>
@@ -75,7 +79,7 @@
 #include "FloatingDockContainer.h"
 #include "DockComponentsFactory.h"
 #include "StatusDialog.h"
-
+#include "DockSplitter.h"
 
 
 /**
@@ -109,7 +113,7 @@ static void appendFeaturStringToWindowTitle(ads::CDockWidget* DockWidget)
 static QIcon svgIcon(const QString& File)
 {
 	// This is a workaround, because in item views SVG icons are not
-	// properly scaled an look blurry or pixelate
+	// properly scaled and look blurry or pixelate
 	QIcon SvgIcon(File);
 	SvgIcon.addPixmap(SvgIcon.pixmap(92));
 	return SvgIcon;
@@ -166,6 +170,8 @@ struct MainWindowPrivate
 	QComboBox* PerspectiveComboBox = nullptr;
 	ads::CDockManager* DockManager = nullptr;
 	ads::CDockWidget* WindowTitleTestDockWidget = nullptr;
+	QPointer<ads::CDockWidget> LastDockedEditor;
+	QPointer<ads::CDockWidget> LastCreatedFloatingEditor;
 
 	MainWindowPrivate(CMainWindow* _public) : _this(_public) {}
 
@@ -352,6 +358,7 @@ struct MainWindowPrivate
 
 
 #ifdef Q_OS_WIN
+#if (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
 	/**
 	 * Creates an ActiveX widget on windows
 	 */
@@ -365,6 +372,7 @@ struct MainWindowPrivate
 	   return DockWidget;
 	}
 #endif
+#endif
 
 };
 
@@ -409,6 +417,22 @@ void MainWindowPrivate::createContent()
 	DockWidget = createCalendarDockWidget();
 	DockWidget->setTabToolTip(QString("Tab ToolTip\nHodie est dies magna"));
 	auto DockArea = DockManager->addDockWidget(ads::CenterDockWidgetArea, DockWidget, TopDockArea);
+    // Now we create a action to test resizing of DockArea widget
+	auto Action = ui.menuTests->addAction(QString("Resize %1").arg(DockWidget->windowTitle()));
+	QObject::connect(Action, &QAction::triggered, [DockArea]()
+	{
+		// Resizing only works, if the Splitter is visible and has a valid
+		// sizes
+		auto Splitter = ads::internal::findParent<ads::CDockSplitter*>(DockArea);
+		if (!Splitter)
+		{
+			return;
+		}
+		// We change the sizes of the splitter that contains the Calendar 1 widget
+		// to resize the dock widget
+		int Width = Splitter->width();
+		Splitter->setSizes({Width * 2/3, Width * 1/3});
+	});
 
 	// Now we add a custom button to the dock area title bar that will create
 	// new editor widgets when clicked
@@ -435,18 +459,30 @@ void MainWindowPrivate::createContent()
 	DockManager->addDockWidget(ads::CenterDockWidgetArea, createLongTextLabelDockWidget(), RighDockArea);
 	DockManager->addDockWidget(ads::CenterDockWidgetArea, createLongTextLabelDockWidget(), BottomDockArea);
 
-    auto Action = ui.menuTests->addAction(QString("Set %1 Floating").arg(DockWidget->windowTitle()));
+    Action = ui.menuTests->addAction(QString("Set %1 Floating").arg(DockWidget->windowTitle()));
     DockWidget->connect(Action, SIGNAL(triggered()), SLOT(setFloating()));
     Action = ui.menuTests->addAction(QString("Set %1 As Current Tab").arg(DockWidget->windowTitle()));
     DockWidget->connect(Action, SIGNAL(triggered()), SLOT(setAsCurrentTab()));
     Action = ui.menuTests->addAction(QString("Raise %1").arg(DockWidget->windowTitle()));
     DockWidget->connect(Action, SIGNAL(triggered()), SLOT(raise()));
 
+    // Test hidden floating dock widget
+    DockWidget = createLongTextLabelDockWidget();
+    DockManager->addDockWidgetFloating(DockWidget);
+    DockWidget->toggleView(false);
+
+    // Test visible floating dock widget
+    DockWidget = createCalendarDockWidget();
+    DockManager->addDockWidgetFloating(DockWidget);
+
+
 #ifdef Q_OS_WIN
+#if (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
     if (!ads::CDockManager::testConfigFlag(ads::CDockManager::OpaqueUndocking))
     {
     	DockManager->addDockWidget(ads::CenterDockWidgetArea, createActiveXWidget(), RighDockArea);
     }
+#endif
 #endif
 
 	for (auto DockWidget : DockManager->dockWidgetsMap())
@@ -603,12 +639,20 @@ CMainWindow::CMainWindow(QWidget *parent) :
 	// uncomment if you would like to enable an equal distribution of the
 	// available size of a splitter to all contained dock widgets
 	// CDockManager::setConfigFlag(CDockManager::EqualSplitOnInsertion, true);
+	
+	// uncomment if you would like to close tabs with the middle mouse button, web browser style
+	// CDockManager::setConfigFlag(CDockManager::MiddleMouseButtonClosesTab, true);
 
 	// Now create the dock manager and its content
 	d->DockManager = new CDockManager(this);
 
+ #if (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
 	connect(d->PerspectiveComboBox, SIGNAL(activated(const QString&)),
 		d->DockManager, SLOT(openPerspective(const QString&)));
+ #else
+    connect(d->PerspectiveComboBox, SIGNAL(textActivated(const QString&)),
+        d->DockManager, SLOT(openPerspective(const QString&)));
+ #endif
 
 	d->createContent();
 	// Default window geometry - center on screen
@@ -711,16 +755,39 @@ void CMainWindow::createEditor()
 	bool Floating = vFloating.isValid() ? vFloating.toBool() : true;
 	auto DockWidget = d->createEditorWidget();
 	DockWidget->setFeature(ads::CDockWidget::DockWidgetDeleteOnClose, true);
+	DockWidget->setFeature(ads::CDockWidget::DockWidgetForceCloseWithArea, true);
     connect(DockWidget, SIGNAL(closeRequested()), SLOT(onEditorCloseRequested()));
 
     if (Floating)
     {
 		auto FloatingWidget = d->DockManager->addDockWidgetFloating(DockWidget);
 		FloatingWidget->move(QPoint(20, 20));
+		d->LastCreatedFloatingEditor = DockWidget;
+		d->LastDockedEditor.clear();
     }
     else
     {
-    	d->DockManager->addDockWidget(ads::TopDockWidgetArea, DockWidget);
+    	ads::CDockAreaWidget* EditorArea = d->LastDockedEditor ? d->LastDockedEditor->dockAreaWidget() : nullptr;
+    	if (EditorArea)
+    	{
+    		std::cout << "DockAreaCount before: " << EditorArea->dockContainer()->dockAreaCount() << std::endl;
+    		d->DockManager->setConfigFlag(ads::CDockManager::EqualSplitOnInsertion, true);
+    		d->DockManager->addDockWidget(ads::RightDockWidgetArea, DockWidget, EditorArea);
+    		std::cout << "DockAreaCount after: " << DockWidget->dockContainer()->dockAreaCount() << std::endl;
+    	}
+    	else
+    	{
+    		if (d->LastCreatedFloatingEditor)
+    		{
+    			std::cout << "LastCreated" << std::endl;
+    			d->DockManager->addDockWidget(ads::RightDockWidgetArea, DockWidget, d->LastCreatedFloatingEditor->dockAreaWidget());
+    		}
+    		else
+    		{
+    			d->DockManager->addDockWidget(ads::TopDockWidgetArea, DockWidget);
+    		}
+    	}
+    	d->LastDockedEditor = DockWidget;
     }
 }
 

demo/demo.pro

@@ -4,8 +4,12 @@ TARGET = AdvancedDockingSystemDemo
 DESTDIR = $${ADS_OUT_ROOT}/lib
 QT += core gui widgets
 
-win32 {
-QT += axcontainer
+include(../ads.pri)
+
+lessThan(QT_MAJOR_VERSION, 6) {
+    win32 {
+        QT += axcontainer
+    }
 }
 
 CONFIG += c++14
@@ -34,21 +38,6 @@ RESOURCES += demo.qrc
 
 LIBS += -L$${ADS_OUT_ROOT}/lib
 
-# Dependency: AdvancedDockingSystem (shared)
-CONFIG(debug, debug|release){
-    win32 {
-        LIBS += -lqtadvanceddockingd
-    }
-    else:mac {
-        LIBS += -lqtadvanceddocking_debug
-    }
-    else {
-        LIBS += -lqtadvanceddocking
-    }
-}
-else{
-    LIBS += -lqtadvanceddocking
-}
 
 INCLUDEPATH += ../src
 DEPENDPATH += ../src

demo/main.cpp

@@ -35,9 +35,11 @@ void myMessageOutput(QtMsgType type, const QMessageLogContext &context, const QS
 
 int main(int argc, char *argv[])
 {
+#if (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
 	QCoreApplication::setAttribute(Qt::AA_UseHighDpiPixmaps);
 #if QT_VERSION >= 0x050600
     QGuiApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
+#endif
 #endif
 	std::shared_ptr<int> b;
 	QApplication a(argc, argv);

demo/main.py

@@ -65,7 +65,7 @@ def append_feature_string_to_window_title(dock_widget: QtAds.CDockWidget):
 def svg_icon(filename: str):
     '''Helper function to create an SVG icon'''
     # This is a workaround, because because in item views SVG icons are not
-    # properly scaled an look blurry or pixelate
+    # properly scaled and look blurry or pixelate
     icon = QIcon(filename)
     icon.addPixmap(icon.pixmap(92))
     return icon
@@ -104,6 +104,8 @@ class MainWindow(MainWindowUI, MainWindowBase):
         self.perspective_list_action = None
         self.perspective_combo_box = None
         self.dock_manager = None
+        self.window_title_test_dock_widget = None
+        self.last_docked_editor = None
 
         self.setupUi(self)
         self.create_actions()
@@ -184,6 +186,7 @@ class MainWindow(MainWindowUI, MainWindowBase):
         # special_dock_area.setAllowedAreas(QtAds.LeftDockWidgetArea | QtAds.RightDockWidgetArea) # just for testing
         
         dock_widget = self.create_long_text_label_dock_widget()
+        self.window_title_test_dock_widget = dock_widget
         dock_widget.setFeature(QtAds.CDockWidget.DockWidgetFocusable, False)
         self.dock_manager.addDockWidget(QtAds.LeftDockWidgetArea, dock_widget)
         file_system_widget = self.create_file_system_tree_dock_widget()
@@ -203,8 +206,8 @@ class MainWindow(MainWindowUI, MainWindowBase):
         QtAds.CDockComponentsFactory.setFactory(CCustomComponentsFactory())
         top_dock_area = self.dock_manager.addDockWidget(QtAds.TopDockWidgetArea, file_system_widget)
         # Uncomment the next line if you would like to test the
-        # setHideSingleWidgetTitleBar() functionality
-        # top_dock_area.setHideSingleWidgetTitleBar(True)
+        # HideSingleWidgetTitleBar functionality
+        # top_dock_area.setDockAreaFlag(QtAds.CDockAreaWidget.HideSingleWidgetTitleBar, True)
         QtAds.CDockComponentsFactory.resetDefaultFactory()
 
         # We create a calendar widget and clear all flags to prevent the dock area
@@ -212,6 +215,17 @@ class MainWindow(MainWindowUI, MainWindowBase):
         dock_widget = self.create_calendar_dock_widget()
         dock_widget.setTabToolTip("Tab ToolTip\nHodie est dies magna")
         dock_area = self.dock_manager.addDockWidget(QtAds.CenterDockWidgetArea, dock_widget, top_dock_area)
+        # Now we create a action to test resizing of DockArea widget
+        action = self.menuTests.addAction("Resize {}".format(dock_widget.windowTitle()))
+        def action_triggered():
+            splitter = QtAds.internal.findParent(QtAds.CDockSplitter, dock_area)
+            if not splitter:
+                return
+            # We change the sizes of the splitter that contains the Calendar 1 widget
+            # to resize the dock widget
+            width = splitter.width()
+            splitter.setSizes([width * 2/3, width * 1/3])
+        action.triggered.connect(action_triggered)
 
         # Now we add a custom button to the dock area title bar that will create
         # new editor widgets when clicked
@@ -354,16 +368,22 @@ class MainWindow(MainWindowUI, MainWindowBase):
     def create_editor(self):
         sender = self.sender()
         floating = sender.property("Floating")
-        print("Floating:", floating)
         dock_widget = self.create_editor_widget()
         dock_widget.setFeature(QtAds.CDockWidget.DockWidgetDeleteOnClose, True)
+        dock_widget.setFeature(QtAds.CDockWidget.DockWidgetForceCloseWithArea, True)
         dock_widget.closeRequested.connect(self.on_editor_close_requested)
         
         if floating:
             floating_widget = self.dock_manager.addDockWidgetFloating(dock_widget)
             floating_widget.move(QPoint(20, 20))
         else:
-            self.dock_manager.addDockWidget(QtAds.TopDockWidgetArea, dock_widget)
+            editor_area = self.last_docked_editor.dockAreaWidget() if self.last_docked_editor is not None else None
+            if editor_area is not None:
+                self.dock_manager.setConfigFlag(QtAds.CDockManager.EqualSplitOnInsertion, True)
+                self.dock_manager.addDockWidget(QtAds.RightDockWidgetArea, dock_widget, editor_area)
+            else:
+                self.dock_manager.addDockWidget(QtAds.TopDockWidgetArea, dock_widget)
+            self.last_docked_editor = dock_widget
             
     def on_editor_close_requested(self):
         dock_widget = self.sender()
@@ -382,6 +402,16 @@ class MainWindow(MainWindowUI, MainWindowBase):
         dialog = CStatusDialog(self.dock_manager)
         dialog.exec_()
 
+
+    def toggle_dock_widget_window_title(self):
+        title = self.window_title_test_dock_widget.windowTitle()
+        i = title.find(" (Test) ")
+        if i == -1:
+            title += " (Test) "
+        else:
+            title = title[i]
+        self.window_title_test_dock_widget.setWindowTitle(title)
+
     def save_state(self):
         '''
         Saves the dock manager state and the main window geometry

doc/user-guide.md

@@ -24,6 +24,23 @@
   - [`FloatingContainerHasWidgetIcon`](#floatingcontainerhaswidgeticon)
   - [`HideSingleCentralWidgetTitleBar`](#hidesinglecentralwidgettitlebar)
   - [`FocusHighlighting`](#focushighlighting)
+  - [`EqualSplitOnInsertion`](#equalsplitoninsertion)
+  - [`FloatingContainerForceNativeTitleBar` (Linux only)](#floatingcontainerforcenativetitlebar-linux-only)
+  - [`FloatingContainerForceQWidgetTitleBar` (Linux only)](#floatingcontainerforceqwidgettitlebar-linux-only)
+  - [`MiddleMouseButtonClosesTab`](#middlemousebuttonclosestab)
+- [DockWidget Feature Flags](#dockwidget-feature-flags)
+  - [`DockWidgetClosable`](#dockwidgetclosable)
+  - [`DockWidgetMovable`](#dockwidgetmovable)
+  - [`DockWidgetFloatable`](#dockwidgetfloatable)
+  - [`DockWidgetDeleteOnClose`](#dockwidgetdeleteonclose)
+  - [`CustomCloseHandling`](#customclosehandling)
+  - [`DockWidgetFocusable`](#dockwidgetfocusable)
+  - [`DockWidgetForceCloseWithArea`](#dockwidgetforceclosewitharea)
+  - [`NoTab`](#notab)
+  - [`DeleteContentOnClose`](#deletecontentonclose)
+- [Central Widget](#central-widget)
+- [Empty Dock Area](#empty-dock-area)
+- [Custom Close Handling](#custom-close-handling)
 - [Styling](#styling)
   - [Disabling the Internal Style Sheet](#disabling-the-internal-style-sheet)
 
@@ -409,6 +426,188 @@ bool CMainWindow::eventFilter(QObject *watched, QEvent *event)
 }
 ```
 
+### `EqualSplitOnInsertion`
+
+This flag configures how the space is distributed if a new dock widget is
+inserted into an existing dock area. The flag is disabled by default. If 3 
+dock widgets are inserted with the following code
+
+```c++
+d->DockManager->addDockWidget(ads::RightDockWidgetArea, DockWidget, EditorArea);
+```
+
+then this is the result, if the flag is disabled:
+
+![EqualSplitOnInsertion false](cfg_flag_EqualSplitOnInsertion_false.png)
+
+If the flag is enabled, then the space is equally distributed to all widgets 
+in a  splitter:
+
+![EqualSplitOnInsertion true](cfg_flag_EqualSplitOnInsertion_true.png)
+
+
+### `FloatingContainerForceNativeTitleBar` (Linux only)
+
+Since release 3.6 the library supports native title bars and window decorations
+for floating widgets on Linux (thanks to a user contribution).
+Native title bars and window decorations are supported by most Linux window
+managers, such as Compiz or Xfwm. Some window managers like KWin do not properly
+support this feature. Native floating widgets look better because of the native
+styling and the support all window manager features like snapping to window
+borders or maximizing. The library tries to detect the window manager during
+runtime and activates native window decorations if possible:
+
+![FloatingContainerForceNativeTitleBar true](cfg_flag_FloatingContainerForceNativeTitleBar_true.png)
+
+If you would like to overwrite this autodetection, then you can  activate this
+flag to force native window titlebars. You can overwrite autodetection and this
+flag, if you set the environment variable `ADS_UseNativeTitle` to 0 or 1.
+
+### `FloatingContainerForceQWidgetTitleBar` (Linux only)
+
+If your window manager (i.e. KWin) does not properly support native floating
+windows, the docking library falls back to QWidget based floating widget
+title bars.
+
+![FloatingContainerForceNativeTitleBar false](cfg_flag_FloatingContainerForceNativeTitleBar_false.png)
+
+If you would like to overwrite autodetection, then you can activate this flag
+to force QWidget based title bars. You can overwrite autodetection and this
+flag, if you set the environment variable `ADS_UseNativeTitle` to 0 or 1.
+
+### `MiddleMouseButtonClosesTab`
+
+If the flag is set, the user can use the mouse middle button to close the tab
+under the mouse. So you do not need to exactly hit the tab close button to
+close tab. Just click with the middle mouse button on a tab like this is
+possible in various web browsers.
+
+![MiddleMouseButtonClosesTab true](cfg_flag_MiddleMouseButtonClosesTab.gif)
+
+## DockWidget Feature Flags
+
+### `DockWidgetClosable`
+
+If set, the dock widget will have a close button.
+
+### `DockWidgetMovable`
+
+If a dock widget is movable, then it and can be moved to a new position in the
+current dock container. Disable this flag to prevent moving of a dock widget
+via mouse. If the `OpaqueUndocking` configuration flag is set, then dock widgets
+are immediately undocked into floating widgets. That means, moving is only
+possible in this case, if the dock widget is also floatable (feature flag
+`DockWidgetFloatable` is set).
+
+### `DockWidgetFloatable`
+
+If set, a dock widget can be dragged into a floating window.
+
+### `DockWidgetDeleteOnClose`
+
+Deletes the dock widget and its content when it is closed.
+
+### `CustomCloseHandling`
+
+Clicking the close button will not close the dock widget but emits the
+`closeRequested()` signal instead. This allows the application to implement
+a custom close handling.
+
+### `DockWidgetFocusable`
+
+If this is enabled, a dock widget can get focus highlighting.
+
+### `DockWidgetForceCloseWithArea`
+
+A dock widget will be closed when the dock area hosting it is closed. If the
+`DockWidgetDeleteOnClose` feature is enabled for a dock widget, then it will
+be deleted, if the user clicks the close button of this dock widget. If the
+user clicks the close button of the dock area that contains this widget,
+then only the visibility of the dock widget is toggled. If this feature flag
+is set, the closing the dock area also closes the dock widget. That means, if
+the dock widget feature `DockWidgetDeleteOnClose` is set for the dock widgets
+in a dock area, then all dock widgets will be deleted if the dock area is closed.
+
+### `NoTab`
+
+A dock widget tab will never be shown if this flag is set.
+
+### `DeleteContentOnClose`
+
+Deletes only the contained widget on close, keeping the dock widget intact and
+in place. Attempts to rebuild the contents widget on show if there is a widget
+factory set. See [issue #365](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/pull/365) for more details.
+
+## Central Widget
+
+The Advanced Docking System has been developed to overcome the limitations of
+the native Qt docking system with its central widget concept. This was the
+reason that until version 3.6 of the library, there was no support for such
+thing like a central widget. Thanks to the contribution of a user the library
+now supports a central widget.
+
+In the Advanced Docking System a central widget is a docking widget that is
+neither closable nor movable or floatable. A central widget has no title bar
+and so it is not possible for the user to hide, close or drag the central
+widget. If there is a central widget, then also the distribution of the sizes
+for the dock widgets around the central widget is different:
+
+- **no central widget (default)** - on resizing the available space is
+distributed to all dock widgets - the size of all dock widgets
+shrinks or grows
+- **with central widget** - on resizing only the central widget is resized - the
+dock widgets around the central widget keep their size (see the animation below)
+
+![Central Widget](central_widget.gif)
+
+To set a central widget, you just need to pass your central dock widget
+to the dock manager `setCentralWidget` function:
+
+```c++
+auto* CentralDockArea = DockManager->setCentralWidget(CentralDockWidget);
+```
+
+See the `centralwidget` example to learn how it works.
+
+> ##### Note
+> The central widget needs to be the first dock widget that is added to the
+> dock manager. The function does not work and returns a `nullptr` if there
+> are already other dock widgets registered. So `setCentralWidget` should be
+> the first function that you call when adding dock widgets.
+
+## Empty Dock Area
+
+Some applications require a fixed DockArea that is always visible, even if it
+does not contain any DockWidgets. I.e. the DockArea is in this case a kind
+of central widget that is always visible (see this
+[issue](https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/issues/199)).
+
+Since version 3.7.1 the advanced docking system supports this feature. The
+`emptydockarea` example shows how this can be implemented with the library. You
+just need to create a dock widget and set the feature flag `CDockWidget::NoTab`.
+This permanently hides the tab widget of this area and removes it from the tab
+menu. For this special dock widget you should also disable all other features
+(movable, closable and floatable) to prevent closing and moving of this widget.
+If you use the `CDockManager::setCentralWidget` function like in the example
+code below, then you don't need to disable these features because this is done
+in the `setCentralWidget` function.
+
+```c++
+QLabel* label = new QLabel();
+label->setText("This is a DockArea which is always visible, even if it does not contain any DockWidgets.");
+label->setAlignment(Qt::AlignCenter);
+CDockWidget* CentralDockWidget = new CDockWidget("CentralWidget");
+CentralDockWidget->setWidget(label);
+CentralDockWidget->setFeature(ads::CDockWidget::NoTab, true);// set the flag before adding the widget to dock manager
+auto* CentralDockArea = DockManager->setCentralWidget(CentralDockWidget);
+```
+
+## Custom Close Handling
+
+Normally clicking the close button of a dock widget will just hide the widget and the user can show it again using the `toggleView()` action of the dock widget. This is meant for user interfaces with a static amount of widgets. But the advanced docking system also supports dynamic dock widgets that will get deleted on close. If you set the dock widget flag `DockWidgetDeleteOnClose` for a certain dock widget, then it will be deleted as soon as you close this dock widget. This enables the implementation of user interfaces with dynamically created editors, like in word processing applications or source code development tools.
+
+When an entire area is closed, the default behavior is to hide the dock widgets it contains regardless of the `DockWidgetDeleteOnClose` flag except if there is only one dock widget. In this special case, the `DockWidgetDeleteOnClose` flag is followed. This behavior can be changed by setting the `DockWidgetForceCloseWithArea` flag to all the dock widgets that needs to be closed with their area.
+
 ## Styling
 
 The Advanced Docking System supports styling via [Qt Style Sheets](https://doc.qt.io/qt-5/stylesheet.html). All components like splitters, tabs, buttons, titlebar and

examples/CMakeLists.txt

@@ -3,4 +3,6 @@ project(QtADSExamples LANGUAGES CXX VERSION ${VERSION_SHORT})
 add_subdirectory(simple)
 add_subdirectory(sidebar)
 add_subdirectory(deleteonclose)
-add_subdirectory(centralwidget)
+add_subdirectory(centralwidget)
+add_subdirectory(emptydockarea)
+add_subdirectory(dockindock)

examples/centralwidget/CMakeLists.txt

@@ -1,6 +1,7 @@
 cmake_minimum_required(VERSION 3.5)
 project(ads_example_centralwidget VERSION ${VERSION_SHORT}) 
-find_package(Qt5 5.5 COMPONENTS Core Gui Widgets REQUIRED)
+find_package(QT NAMES Qt6 Qt5 COMPONENTS Core REQUIRED)
+find_package(Qt${QT_VERSION_MAJOR} 5.5 COMPONENTS Core Gui Widgets REQUIRED)
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
 add_executable(CentralWidgetExample WIN32 
     main.cpp
@@ -9,7 +10,9 @@ add_executable(CentralWidgetExample WIN32
 )
 target_include_directories(CentralWidgetExample PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/../../src")
 target_link_libraries(CentralWidgetExample PRIVATE qtadvanceddocking)
-target_link_libraries(CentralWidgetExample PUBLIC Qt5::Core Qt5::Gui Qt5::Widgets)
+target_link_libraries(CentralWidgetExample PUBLIC Qt${QT_VERSION_MAJOR}::Core 
+                                                  Qt${QT_VERSION_MAJOR}::Gui 
+                                                  Qt${QT_VERSION_MAJOR}::Widgets)
 set_target_properties(CentralWidgetExample PROPERTIES 
     AUTOMOC ON
     AUTORCC ON

examples/centralwidget/centralwidget.pro

@@ -28,23 +28,7 @@ FORMS += \
     mainwindow.ui
 
 LIBS += -L$${ADS_OUT_ROOT}/lib
-
-# Dependency: AdvancedDockingSystem (shared)
-CONFIG(debug, debug|release){
-    win32 {
-        LIBS += -lqtadvanceddockingd
-    }
-    else:mac {
-        LIBS += -lqtadvanceddocking_debug
-    }
-    else {
-        LIBS += -lqtadvanceddocking
-    }
-}
-else{
-    LIBS += -lqtadvanceddocking
-}
-
+include(../../ads.pri)
 INCLUDEPATH += ../../src
 DEPENDPATH += ../../src
 

examples/centralwidget/main.py

@@ -0,0 +1,106 @@
+import os
+import sys
+
+from PyQt5 import uic
+from PyQt5.QtCore import Qt, QTimer, QDir, QSignalBlocker
+from PyQt5.QtGui import QCloseEvent, QIcon
+from PyQt5.QtWidgets import (QApplication, QLabel, QCalendarWidget, QFrame, QTreeView,
+                             QTableWidget, QFileSystemModel, QPlainTextEdit, QToolBar,
+                             QWidgetAction, QComboBox, QAction, QSizePolicy, QInputDialog)
+
+from PyQtAds import QtAds
+
+UI_FILE = os.path.join(os.path.dirname(__file__), 'mainwindow.ui')
+MainWindowUI, MainWindowBase = uic.loadUiType(UI_FILE)
+    
+class MainWindow(MainWindowUI, MainWindowBase):
+
+    def __init__(self, parent=None):
+        super().__init__(parent)
+
+        self.setupUi(self)
+ 
+        QtAds.CDockManager.setConfigFlag(QtAds.CDockManager.OpaqueSplitterResize, True)
+        QtAds.CDockManager.setConfigFlag(QtAds.CDockManager.XmlCompressionEnabled, False)
+        QtAds.CDockManager.setConfigFlag(QtAds.CDockManager.FocusHighlighting, True)
+        self.dock_manager = QtAds.CDockManager(self)
+        
+        # Set central widget
+        text_edit = QPlainTextEdit()
+        text_edit.setPlaceholderText("This is the central editor. Enter your text here.")
+        central_dock_widget = QtAds.CDockWidget("CentralWidget")
+        central_dock_widget.setWidget(text_edit)
+        central_dock_area = self.dock_manager.setCentralWidget(central_dock_widget)
+        central_dock_area.setAllowedAreas(QtAds.DockWidgetArea.OuterDockAreas)
+        
+        # create other dock widgets
+        table = QTableWidget()
+        table.setColumnCount(3)
+        table.setRowCount(10)
+        table_dock_widget = QtAds.CDockWidget("Table 1")
+        table_dock_widget.setWidget(table)
+        table_dock_widget.setMinimumSizeHintMode(QtAds.CDockWidget.MinimumSizeHintFromDockWidget)
+        table_dock_widget.resize(250, 150)
+        table_dock_widget.setMinimumSize(200, 150)
+        table_area = self.dock_manager.addDockWidget(QtAds.DockWidgetArea.LeftDockWidgetArea, table_dock_widget)
+        self.menuView.addAction(table_dock_widget.toggleViewAction())
+        
+        table = QTableWidget()
+        table.setColumnCount(5)
+        table.setRowCount(1020)
+        table_dock_widget = QtAds.CDockWidget("Table 2")
+        table_dock_widget.setWidget(table)
+        table_dock_widget.setMinimumSizeHintMode(QtAds.CDockWidget.MinimumSizeHintFromDockWidget)
+        table_dock_widget.resize(250, 150)
+        table_dock_widget.setMinimumSize(200, 150)
+        table_area = self.dock_manager.addDockWidget(QtAds.DockWidgetArea.BottomDockWidgetArea, table_dock_widget, table_area)
+        self.menuView.addAction(table_dock_widget.toggleViewAction())
+
+        properties_table = QTableWidget()
+        properties_table.setColumnCount(3)
+        properties_table.setRowCount(10)
+        properties_dock_widget = QtAds.CDockWidget("Properties")
+        properties_dock_widget.setWidget(properties_table)
+        properties_dock_widget.setMinimumSizeHintMode(QtAds.CDockWidget.MinimumSizeHintFromDockWidget)
+        properties_dock_widget.resize(250, 150)
+        properties_dock_widget.setMinimumSize(200, 150)
+        self.dock_manager.addDockWidget(QtAds.DockWidgetArea.RightDockWidgetArea, properties_dock_widget, central_dock_area)
+        self.menuView.addAction(properties_dock_widget.toggleViewAction())
+        
+        self.create_perspective_ui()
+        
+    def create_perspective_ui(self):
+        save_perspective_action = QAction("Create Perspective", self)
+        save_perspective_action.triggered.connect(self.save_perspective)
+        perspective_list_action = QWidgetAction(self)
+        self.perspective_combobox = QComboBox(self)
+        self.perspective_combobox.setSizeAdjustPolicy(QComboBox.AdjustToContents)
+        self.perspective_combobox.setSizePolicy(QSizePolicy.Preferred, QSizePolicy.Preferred)
+        self.perspective_combobox.activated[str].connect(self.dock_manager.openPerspective)
+        perspective_list_action.setDefaultWidget(self.perspective_combobox)
+        self.toolBar.addSeparator()
+        self.toolBar.addAction(perspective_list_action)
+        self.toolBar.addAction(save_perspective_action)
+        
+    def save_perspective(self):
+        perspective_name, ok = QInputDialog.getText(self, "Save Perspective", "Enter Unique name:")
+        if not ok or not perspective_name:
+            return
+        
+        self.dock_manager.addPerspective(perspective_name)
+        blocker = QSignalBlocker(self.perspective_combobox)
+        self.perspective_combobox.clear()
+        self.perspective_combobox.addItems(self.dock_manager.perspectiveNames())
+        self.perspective_combobox.setCurrentText(perspective_name)
+        
+    def closeEvent(self, event: QCloseEvent):
+        self.dock_manager.deleteLater()
+        super().closeEvent(event)
+
+
+if __name__ == '__main__':
+    app = QApplication(sys.argv)
+    
+    w = MainWindow()
+    w.show()
+    app.exec_()

examples/centralwidget/mainwindow.cpp

@@ -15,6 +15,8 @@
 #include <QFileDialog>
 #include <QSettings>
 #include <QMessageBox>
+#include <QPlainTextEdit>
+#include <QToolBar>
 
 #include "DockAreaWidget.h"
 #include "DockAreaTitleBar.h"
@@ -24,6 +26,7 @@
 
 using namespace ads;
 
+
 CMainWindow::CMainWindow(QWidget *parent)
     : QMainWindow(parent)
     , ui(new Ui::CMainWindow)
@@ -31,42 +34,43 @@ CMainWindow::CMainWindow(QWidget *parent)
     ui->setupUi(this);
     CDockManager::setConfigFlag(CDockManager::OpaqueSplitterResize, true);
     CDockManager::setConfigFlag(CDockManager::XmlCompressionEnabled, false);
+    CDockManager::setConfigFlag(CDockManager::FocusHighlighting, true);
     DockManager = new CDockManager(this);
 
     // Set central widget
-    QCalendarWidget* calendar = new QCalendarWidget();
+    QPlainTextEdit* w = new QPlainTextEdit();
+	w->setPlaceholderText("This is the central editor. Enter your text here.");
     CDockWidget* CentralDockWidget = new CDockWidget("CentralWidget");
-    CentralDockWidget->setWidget(calendar);
+    CentralDockWidget->setWidget(w);
     auto* CentralDockArea = DockManager->setCentralWidget(CentralDockWidget);
     CentralDockArea->setAllowedAreas(DockWidgetArea::OuterDockAreas);
 
     // create other dock widgets
-    QTreeView* fileTree = new QTreeView();
-    fileTree->setFrameShape(QFrame::NoFrame);
-    QFileSystemModel* fileModel = new QFileSystemModel(fileTree);
-    fileModel->setRootPath(QDir::currentPath());
-    fileTree->setModel(fileModel);
-    CDockWidget* DataDockWidget = new CDockWidget("File system");
-    DataDockWidget->setWidget(fileTree);
-    DataDockWidget->resize(150, 250);
-    DataDockWidget->setMinimumSize(100, 250);
-    auto* fileArea = DockManager->addDockWidget(DockWidgetArea::LeftDockWidgetArea, DataDockWidget, CentralDockArea);
-    ui->menuView->addAction(DataDockWidget->toggleViewAction());
-
     QTableWidget* table = new QTableWidget();
     table->setColumnCount(3);
     table->setRowCount(10);
-    CDockWidget* TableDockWidget = new CDockWidget("Table");
+    CDockWidget* TableDockWidget = new CDockWidget("Table 1");
     TableDockWidget->setWidget(table);
     TableDockWidget->setMinimumSizeHintMode(CDockWidget::MinimumSizeHintFromDockWidget);
     TableDockWidget->resize(250, 150);
     TableDockWidget->setMinimumSize(200,150);
-    DockManager->addDockWidget(DockWidgetArea::BottomDockWidgetArea, TableDockWidget, fileArea);
+    auto TableArea = DockManager->addDockWidget(DockWidgetArea::LeftDockWidgetArea, TableDockWidget);
+    ui->menuView->addAction(TableDockWidget->toggleViewAction());
+
+    table = new QTableWidget();
+    table->setColumnCount(5);
+    table->setRowCount(1020);
+    TableDockWidget = new CDockWidget("Table 2");
+    TableDockWidget->setWidget(table);
+    TableDockWidget->setMinimumSizeHintMode(CDockWidget::MinimumSizeHintFromDockWidget);
+    TableDockWidget->resize(250, 150);
+    TableDockWidget->setMinimumSize(200,150);
+    DockManager->addDockWidget(DockWidgetArea::BottomDockWidgetArea, TableDockWidget, TableArea);
     ui->menuView->addAction(TableDockWidget->toggleViewAction());
 
     QTableWidget* propertiesTable = new QTableWidget();
-    table->setColumnCount(3);
-    table->setRowCount(10);
+    propertiesTable->setColumnCount(3);
+    propertiesTable->setRowCount(10);
     CDockWidget* PropertiesDockWidget = new CDockWidget("Properties");
     PropertiesDockWidget->setWidget(propertiesTable);
     PropertiesDockWidget->setMinimumSizeHintMode(CDockWidget::MinimumSizeHintFromDockWidget);
@@ -74,6 +78,8 @@ CMainWindow::CMainWindow(QWidget *parent)
     PropertiesDockWidget->setMinimumSize(200,150);
     DockManager->addDockWidget(DockWidgetArea::RightDockWidgetArea, PropertiesDockWidget, CentralDockArea);
     ui->menuView->addAction(PropertiesDockWidget->toggleViewAction());
+
+    createPerspectiveUi();
 }
 
 CMainWindow::~CMainWindow()
@@ -81,3 +87,47 @@ CMainWindow::~CMainWindow()
     delete ui;
 }
 
+
+void CMainWindow::createPerspectiveUi()
+{
+	SavePerspectiveAction = new QAction("Create Perspective", this);
+	connect(SavePerspectiveAction, SIGNAL(triggered()), SLOT(savePerspective()));
+	PerspectiveListAction = new QWidgetAction(this);
+	PerspectiveComboBox = new QComboBox(this);
+	PerspectiveComboBox->setSizeAdjustPolicy(QComboBox::AdjustToContents);
+	PerspectiveComboBox->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Preferred);
+	connect(PerspectiveComboBox, SIGNAL(activated(const QString&)),
+		DockManager, SLOT(openPerspective(const QString&)));
+	PerspectiveListAction->setDefaultWidget(PerspectiveComboBox);
+	ui->toolBar->addSeparator();
+	ui->toolBar->addAction(PerspectiveListAction);
+	ui->toolBar->addAction(SavePerspectiveAction);
+}
+
+
+void CMainWindow::savePerspective()
+{
+	QString PerspectiveName = QInputDialog::getText(this, "Save Perspective", "Enter unique name:");
+	if (PerspectiveName.isEmpty())
+	{
+		return;
+	}
+
+	DockManager->addPerspective(PerspectiveName);
+	QSignalBlocker Blocker(PerspectiveComboBox);
+	PerspectiveComboBox->clear();
+	PerspectiveComboBox->addItems(DockManager->perspectiveNames());
+	PerspectiveComboBox->setCurrentText(PerspectiveName);
+}
+
+
+//============================================================================
+void CMainWindow::closeEvent(QCloseEvent* event)
+{
+    // Delete dock manager here to delete all floating widgets. This ensures
+    // that all top level windows of the dock manager are properly closed
+    DockManager->deleteLater();
+	QMainWindow::closeEvent(event);
+}
+
+

examples/centralwidget/mainwindow.h

@@ -2,6 +2,8 @@
 #define MAINWINDOW_H
 
 #include <QMainWindow>
+#include <QComboBox>
+#include <QWidgetAction>
 
 #include "DockManager.h"
 #include "DockAreaWidget.h"
@@ -19,14 +21,23 @@ public:
     CMainWindow(QWidget *parent = nullptr);
     ~CMainWindow();
 
+protected:
+	virtual void closeEvent(QCloseEvent* event) override;
+
 private:
-    static const QString kTableTopLayout;
-    static const QString kTableBottomLayout;
+	QAction* SavePerspectiveAction = nullptr;
+	QWidgetAction* PerspectiveListAction = nullptr;
+	QComboBox* PerspectiveComboBox = nullptr;
 
     Ui::CMainWindow *ui;
 
     ads::CDockManager* DockManager;
     ads::CDockAreaWidget* StatusDockArea;
     ads::CDockWidget* TimelineDockWidget;
+
+    void createPerspectiveUi();
+
+private slots:
+	void savePerspective();
 };
 #endif // MAINWINDOW_H

examples/centralwidget/mainwindow.ui

@@ -30,6 +30,17 @@
    </widget>
    <addaction name="menuView"/>
   </widget>
+  <widget class="QToolBar" name="toolBar">
+   <property name="windowTitle">
+    <string>toolBar</string>
+   </property>
+   <attribute name="toolBarArea">
+    <enum>TopToolBarArea</enum>
+   </attribute>
+   <attribute name="toolBarBreak">
+    <bool>false</bool>
+   </attribute>
+  </widget>
  </widget>
  <resources/>
  <connections/>

examples/deleteonclose/CMakeLists.txt

@@ -1,13 +1,16 @@
 cmake_minimum_required(VERSION 3.5)
 project(ads_example_deleteonclose VERSION ${VERSION_SHORT}) 
-find_package(Qt5 5.5 COMPONENTS Core Gui Widgets REQUIRED)
+find_package(QT NAMES Qt6 Qt5 COMPONENTS Core REQUIRED)
+find_package(Qt${QT_VERSION_MAJOR} 5.5 COMPONENTS Core Gui Widgets REQUIRED)
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
 add_executable(DeleteOnCloseTest WIN32 
     main.cpp
 )
 target_include_directories(DeleteOnCloseTest PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/../../src")
 target_link_libraries(DeleteOnCloseTest PRIVATE qtadvanceddocking)
-target_link_libraries(DeleteOnCloseTest PUBLIC Qt5::Core Qt5::Gui Qt5::Widgets)
+target_link_libraries(DeleteOnCloseTest PUBLIC Qt${QT_VERSION_MAJOR}::Core 
+                                               Qt${QT_VERSION_MAJOR}::Gui 
+                                               Qt${QT_VERSION_MAJOR}::Widgets)
 set_target_properties(DeleteOnCloseTest PROPERTIES 
     AUTOMOC ON
     CXX_STANDARD 14

examples/deleteonclose/deleteonclose.pro

@@ -17,23 +17,7 @@ SOURCES += main.cpp
 
 
 LIBS += -L$${ADS_OUT_ROOT}/lib
-
-# Dependency: AdvancedDockingSystem (shared)
-CONFIG(debug, debug|release){
-    win32 {
-        LIBS += -lqtadvanceddockingd
-    }
-    else:mac {
-        LIBS += -lqtadvanceddocking_debug
-    }
-    else {
-        LIBS += -lqtadvanceddocking
-    }
-}
-else{
-    LIBS += -lqtadvanceddocking
-}
-
+include(../../ads.pri)
 INCLUDEPATH += ../../src
 DEPENDPATH += ../../src    
 

examples/deleteonclose/main.cpp

@@ -41,19 +41,39 @@ int main(int argc, char *argv[])
         now->widget()->setFocus();
     });
 
-    QAction *action = new QAction("New Delete On Close", &w);
+    QAction *action = new QAction("New [DockWidgetDeleteOnClose]", &w);
     w.menuBar()->addAction(action);
 
     int i = 0;
     QObject::connect(action, &QAction::triggered, [&]() {
-        auto dw = new ads::CDockWidget(QStringLiteral("test doc %1").arg(i++), &w);
+        auto dw = new ads::CDockWidget(QStringLiteral("test %1 [DockWidgetDeleteOnClose]").arg(i++), &w);
         auto editor = new QTextEdit(QStringLiteral("lorem ipsum..."), dw);
         dw->setWidget(editor);
         dw->setFeature(ads::CDockWidget::DockWidgetDeleteOnClose, true);
         auto area = dockManager->addDockWidgetTab(ads::CenterDockWidgetArea, dw);
         qDebug() << "doc dock widget created!" << dw << area;
     });
-
+	
+	auto dw = new ads::CDockWidget(QStringLiteral("test %1 [DeleteContentOnClose]").arg(i++), &w);
+	auto editor = new QTextEdit(QStringLiteral("recreated lorem ipsum......"), dw);
+	dw->setWidget(editor);
+	dw->setFeature(ads::CDockWidget::DeleteContentOnClose, true);
+	dw->setWidgetFactory([](QWidget* dw)
+	{
+		static int timesRecreated = 0;
+		return new QTextEdit(QStringLiteral("recreated lorem ipsum... times %1").arg(++timesRecreated), dw);
+	});
+	auto area = dockManager->addDockWidgetTab(ads::CenterDockWidgetArea, dw);
+	qDebug() << "DeleteContentOnClose dock widget created!" << dw << area;
+	
+	action = new QAction("Toggle [DeleteContentOnClose]", &w);
+    w.menuBar()->addAction(action);
+	
+	QObject::connect(action, &QAction::triggered, [dw]() {
+		dw->toggleView(dw->isClosed());
+		qDebug() << QString("dock widget %1! contents widget %2!").arg(dw->isClosed() ? "closed" : "open", dw->widget() ? "created" : "deleted");
+    });
+	
     action = new QAction("New", &w);
     w.menuBar()->addAction(action);
     QObject::connect(action, &QAction::triggered, [&]() {

examples/dockindock/CMakeLists.txt

@@ -0,0 +1,31 @@
+cmake_minimum_required(VERSION 3.5)
+project(ads_example_dockindock VERSION ${VERSION_SHORT}) 
+find_package(QT NAMES Qt6 Qt5 COMPONENTS Core REQUIRED)
+find_package(Qt${QT_VERSION_MAJOR} 5.5 COMPONENTS Core Gui Widgets REQUIRED)
+set(CMAKE_INCLUDE_CURRENT_DIR ON)
+add_executable(DockInDockExample WIN32 
+    dockindock.cpp
+    dockindockmanager.cpp
+    perspectiveactions.cpp
+    perspectives.cpp
+    main.cpp
+    mainframe.cpp
+)
+target_include_directories(DockInDockExample PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/../../src")
+target_link_libraries(DockInDockExample PRIVATE qtadvanceddocking)
+target_link_libraries(DockInDockExample PUBLIC Qt${QT_VERSION_MAJOR}::Core 
+                                           Qt${QT_VERSION_MAJOR}::Gui 
+                                           Qt${QT_VERSION_MAJOR}::Widgets)
+set_target_properties(DockInDockExample PROPERTIES 
+    AUTOMOC ON
+    AUTORCC ON
+    AUTOUIC ON
+    CXX_STANDARD 14
+    CXX_STANDARD_REQUIRED ON
+    CXX_EXTENSIONS OFF
+    VERSION ${VERSION_SHORT}
+    EXPORT_NAME "Qt Advanced Docking System Simple Example"
+    ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/${ads_PlatformDir}/lib"
+    LIBRARY_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/${ads_PlatformDir}/lib"
+    RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/${ads_PlatformDir}/bin"
+)

examples/dockindock/dockindock.cpp

@@ -0,0 +1,296 @@
+#include "dockindock.h"
+#include "perspectives.h"
+#include "dockindockmanager.h"
+#include "perspectiveactions.h"
+
+#include <QMenu>
+#include <QDir>
+#include <QVBoxLayout>
+#include <QMainWindow>
+#include <QMessageBox>
+#include <QInputDialog>
+
+#include <set>
+#include <assert.h>
+
+using namespace QtAdsUtl;
+
+DockInDockWidget::DockInDockWidget( QWidget* parent, bool canCreateNewGroups, PerspectivesManager* perspectivesManager ) : 
+    DockInDockWidget( parent, (DockInDockWidget*)NULL, perspectivesManager )
+{
+    m_canCreateNewGroups = canCreateNewGroups;
+    m_topLevelDockWidget = this;
+}
+
+DockInDockWidget::DockInDockWidget( QWidget* parent, DockInDockWidget* topLevelDockWidget, PerspectivesManager* perspectivesManager ) : 
+    baseClass( parent ),
+    m_topLevelDockWidget( topLevelDockWidget ),
+    m_canCreateNewGroups( (topLevelDockWidget) ? topLevelDockWidget->m_canCreateNewGroups : false ),
+    m_perspectivesManager( perspectivesManager )
+{
+    QVBoxLayout* layout = new QVBoxLayout(this);
+    layout->setContentsMargins( 0,0,0,0 );
+    layout->addWidget( m_mgr = new DockInDockManager(*this) );
+}
+
+DockInDockWidget::~DockInDockWidget()
+{
+    
+}
+
+ads::CDockAreaWidget* DockInDockWidget::addTabWidget( QWidget* widget, const QString& name, ads::CDockAreaWidget* after )
+{
+    return addTabWidget( widget, name, QIcon(), after );
+}
+
+ads::CDockAreaWidget* DockInDockWidget::addTabWidget( QWidget* widget, const QString& name, QIcon icon, ads::CDockAreaWidget* after )
+{
+    for ( auto existing : getTopLevelDockWidget()->getManager()->allDockWidgets(true,true) )
+    {
+        if ( existing.second->objectName() == name )
+        {
+            QMessageBox::critical( this, "Error", "Name '" + name + "' already in use" );
+            return NULL;
+        }
+    }
+
+    ads::CDockWidget* DockWidget = new ads::CDockWidget(name);
+    DockWidget->setWidget(widget);
+    DockWidget->setIcon( icon );
+
+    // Add the dock widget to the top dock widget area
+    return m_mgr->addDockWidget(ads::CenterDockWidgetArea, DockWidget, after);
+}
+
+bool DockInDockWidget::isTopLevel()
+{
+    return objectName().isEmpty();
+}
+
+QString DockInDockWidget::getGroupNameError( const QString& groupName )
+{
+    if ( groupName.isEmpty() )
+    {
+        return "Group must have a non-empty name";
+    }
+
+    std::vector<DockInDockManager*> dockManagers = m_mgr->allManagers( true, true );
+    for ( auto mgr : dockManagers )
+    {
+        if ( mgr->getGroupName() == groupName )
+            return "Group name '" + groupName + "' already used";
+    }
+
+    return "";
+}
+
+DockInDockWidget* DockInDockWidget::createGroup( const QString& groupName, ads::CDockAreaWidget*& insertPos )
+{
+    return createGroup( groupName, QIcon(), insertPos );
+}
+
+DockInDockWidget* DockInDockWidget::createGroup( const QString& groupName, QIcon icon, ads::CDockAreaWidget*& insertPos )
+{
+    QString error = getGroupNameError( groupName );
+    if ( !error.isEmpty() )
+    {
+        QMessageBox::critical( NULL, "Error", error );
+        return NULL;
+    }
+
+    DockInDockWidget* child = new DockInDockWidget( this, m_topLevelDockWidget, m_perspectivesManager );
+    child->setObjectName( groupName );
+
+    ads::CDockWidget* DockWidget = new ads::CDockWidget(groupName);
+    DockWidget->setWidget(child);
+    DockWidget->setIcon(icon);
+
+    insertPos = m_mgr->addDockWidget(ads::CenterDockWidgetArea, DockWidget, insertPos);
+
+    return child;
+}
+
+void DockInDockWidget::destroyGroup( DockInDockWidget* widgetToRemove )
+{
+    auto topLevelWidget = widgetToRemove->getTopLevelDockWidget();
+
+    if ( topLevelWidget && topLevelWidget != widgetToRemove )
+    {
+        // reaffect all child docks to top-level
+        for ( auto dockwidget : widgetToRemove->getManager()->getWidgetsInGUIOrder() ) // don't use allDockWidgets to preserve sub-groups
+        {
+            MoveDockWidgetAction::move( dockwidget, topLevelWidget->getManager() );
+        }
+        assert( widgetToRemove->getManager()->allDockWidgets( true, true ).empty() );
+
+        // find widget's parent:
+        for ( auto dockwidget : topLevelWidget->getManager()->allDockWidgets( true, true ) )
+        {
+            if ( dockwidget.second->widget() == widgetToRemove )
+            {
+                dockwidget.first->removeDockWidget( dockwidget.second );
+                delete dockwidget.second;
+                //delete widgetToRemove; automatically deleted when dockWidget is deleted
+                widgetToRemove = NULL;
+                break;
+            }
+        }
+
+        assert( widgetToRemove == NULL );
+    }
+    else
+    {
+        assert( false );
+    }
+}
+
+void DockInDockWidget::attachViewMenu( QMenu* menu )
+{
+    connect( menu, SIGNAL(aboutToShow()), this, SLOT(autoFillAttachedViewMenu()) );
+}
+
+void DockInDockWidget::autoFillAttachedViewMenu()
+{
+    QMenu* menu = dynamic_cast<QMenu*>( QObject::sender() );
+
+    if ( menu )
+    {
+        menu->clear();
+        setupViewMenu( menu );
+    }
+    else
+    {
+        assert( false );
+    }
+}
+
+void DockInDockWidget::setupViewMenu( QMenu* menu )
+{
+    std::vector<DockInDockManager*> dockManagers = m_mgr->allManagers( true, true );
+
+    bool hasPerspectivesMenu = false;
+    if ( getTopLevelDockWidget() == this )
+        hasPerspectivesMenu = (m_perspectivesManager != NULL);
+    else
+        assert( false );
+
+    QMenu* organize = menu;
+    if ( hasPerspectivesMenu )
+        organize = menu->addMenu( "Organize" );
+
+    setupMenu( organize, dockManagers );
+
+    if ( hasPerspectivesMenu )
+    {
+        QMenu* perspectives = menu->addMenu( "Perspectives" );
+        fillPerspectivesMenu( perspectives );
+    }
+}
+
+void DockInDockWidget::setupMenu( QMenu* menu, const std::vector<DockInDockManager*>& moveTo )
+{
+    m_mgr->fillViewMenu( menu, moveTo );
+    menu->addSeparator();
+    auto moveMenu = menu->addMenu( "Move" );
+    m_mgr->fillMoveMenu( moveMenu, moveTo );
+}
+
+void DockInDockWidget::fillPerspectivesMenu( QMenu* menu )
+{
+    menu->addAction( "Create perspective...", this, SLOT(createPerspective()) );
+
+    QStringList perspectiveNames;
+    if ( m_perspectivesManager )
+        perspectiveNames = m_perspectivesManager->perspectiveNames();
+
+    if ( !perspectiveNames.isEmpty() )
+    {
+        QMenu* load = menu->addMenu( "Load perspective" );
+        for ( auto name : perspectiveNames )
+            load->addAction( new LoadPerspectiveAction( load, name, *this ) );
+        QMenu* remove = menu->addMenu( "Remove perspective" );
+        for ( auto name : perspectiveNames )
+            remove->addAction( new RemovePerspectiveAction( remove, name, *this ) );
+    }
+}
+
+void DockInDockWidget::setNewPerspectiveDefaultName( const QString& defaultName )
+{
+    m_newPerspectiveDefaultName = defaultName;
+}
+
+void DockInDockWidget::createPerspective()
+{
+    if ( !m_perspectivesManager )
+        return;
+
+    QString name = m_newPerspectiveDefaultName;
+    if ( !m_newPerspectiveDefaultName.isEmpty() )
+    {
+        int index = 2;
+        while ( m_perspectivesManager->perspectiveNames().contains( name ) )
+        {
+            name = m_newPerspectiveDefaultName + " (" + QString::number(index) + ")";
+            ++index;
+        }
+    }
+
+    while ( true )
+    {
+        bool ok = false;
+        name = QInputDialog::getText( NULL, "Create perspective", "Enter perspective name", QLineEdit::Normal, name, &ok );
+        if ( ok )
+        {
+            if ( name.isEmpty() )
+            {
+                QMessageBox::critical( NULL, "Error", "Perspective name cannot be empty" );
+                continue;
+            }
+            else if ( m_perspectivesManager->perspectiveNames().contains( name ) )
+            {
+                if ( QMessageBox::critical( NULL, "Error", "Perspective '" + name + "' already exists, overwrite it?", QMessageBox::Yes | QMessageBox::No, QMessageBox::No ) == QMessageBox::No )
+                    continue;
+            }
+            
+            m_perspectivesManager->addPerspective( name, *this );
+            break;
+        }
+        else
+        {
+            break;
+        }
+    }
+}
+
+static void dumpStatus( std::ostream& str, ads::CDockWidget* widget, const std::string& tab, std::string suffix )
+{
+    DockInDockManager* asMgr = DockInDockManager::dockInAManager( widget );
+    if ( asMgr )
+    {
+        asMgr->parent().dumpStatus( str, tab );
+    }
+    else
+    {
+        str << tab << widget->objectName().toStdString() << suffix << std::endl;
+    }
+}
+
+void DockInDockWidget::dumpStatus( std::ostream& str, std::string tab )
+{
+    str << tab << "Group: " << getManager()->getGroupName().toStdString() << std::endl;
+    tab += "   ";
+    std::set<ads::CDockWidget*> visibleWidgets;
+    for ( auto widget : getManager()->getWidgetsInGUIOrder() )
+    {
+        visibleWidgets.insert( widget );
+        ::dumpStatus( str, widget, tab, "" );
+    }
+
+    for ( auto closed : getManager()->dockWidgetsMap() )
+    {
+        if ( visibleWidgets.find( closed ) == visibleWidgets.end() )
+        {
+            ::dumpStatus( str, closed, tab, " (closed)" );
+        }
+    }
+}

examples/dockindock/dockindock.h

@@ -0,0 +1,80 @@
+#pragma once
+
+#include <QWidget>
+#include <QMap>
+
+#include <memory>
+#include <ostream>
+
+class QMenu;
+
+namespace ads
+{
+    class CDockAreaWidget;
+}
+
+namespace QtAdsUtl
+{
+
+class DockInDockManager;
+class PerspectivesManager;
+// tab of tab example for https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/issues/306
+class DockInDockWidget : public QWidget
+{
+    typedef QWidget baseClass;
+
+    Q_OBJECT
+
+public:
+    DockInDockWidget( QWidget* parent, bool canCreateNewGroups, PerspectivesManager* perspectivesManager );
+    ~DockInDockWidget() override; 
+
+    ads::CDockAreaWidget* addTabWidget( QWidget* widget, const QString& name, ads::CDockAreaWidget* after );
+    DockInDockWidget* createGroup( const QString& groupName, ads::CDockAreaWidget*& insertPos );
+
+    ads::CDockAreaWidget* addTabWidget( QWidget* widget, const QString& name, QIcon icon, ads::CDockAreaWidget* after );
+    DockInDockWidget* createGroup( const QString& groupName, QIcon icon, ads::CDockAreaWidget*& insertPos );
+    
+    QString getGroupNameError( const QString& groupName );
+    void destroyGroup( DockInDockWidget* widget );
+
+    /** Manually fill a given view menu */
+    void setupViewMenu( QMenu* menu );
+
+    /** Attach a view menu that will be automatically fill */
+    void attachViewMenu( QMenu* menu );
+
+    bool isTopLevel();
+    void setupMenu( QMenu* menu, const std::vector<DockInDockManager*>& moveTo );
+
+    inline DockInDockManager* getManager() { return m_mgr; }
+    inline DockInDockWidget* getTopLevelDockWidget() { return m_topLevelDockWidget; }
+
+    inline bool canCreateNewGroups() const { return m_canCreateNewGroups; }
+
+    void dumpStatus( std::ostream& str, std::string tab = "" );
+
+    inline PerspectivesManager* getPerspectivesManager() { return m_perspectivesManager; }
+
+    void setNewPerspectiveDefaultName( const QString& defaultName );
+
+private slots:
+    void autoFillAttachedViewMenu();
+    void createPerspective();
+
+private:
+    DockInDockManager* m_mgr;
+    DockInDockWidget* m_topLevelDockWidget;
+
+    bool m_canCreateNewGroups;
+
+    DockInDockWidget( QWidget* parent, DockInDockWidget* topLevelDockWidget,  PerspectivesManager* perspectivesManager );
+
+    PerspectivesManager* m_perspectivesManager;
+    QString m_newPerspectiveDefaultName;
+
+    void fillPerspectivesMenu( QMenu* menu );
+};
+
+}
+

examples/dockindock/dockindock.pro

@@ -0,0 +1,35 @@
+ADS_OUT_ROOT = $${OUT_PWD}/../..
+
+QT += core gui widgets
+
+TARGET = DockInDock
+DESTDIR = $${ADS_OUT_ROOT}/lib
+TEMPLATE = app
+CONFIG += c++14
+CONFIG += debug_and_release
+adsBuildStatic {
+    DEFINES += ADS_STATIC
+}
+
+DEFINES += QT_DEPRECATED_WARNINGS
+
+SOURCES += \
+        dockindock.cpp \
+        dockindockmanager.cpp \
+        perspectiveactions.cpp \
+        perspectives.cpp \
+        main.cpp \
+        mainframe.cpp
+
+HEADERS += \
+        dockindock.h \
+        dockindockmanager.h \
+        perspectiveactions.h \
+        perspectives.h \
+        mainframe.h      
+
+LIBS += -L$${ADS_OUT_ROOT}/lib
+include(../../ads.pri)
+INCLUDEPATH += ../../src
+DEPENDPATH += ../../src    
+

examples/dockindock/dockindock.py

@@ -0,0 +1,203 @@
+import sys
+
+from PyQt5.QtWidgets import (QApplication, QWidget, QVBoxLayout, QMessageBox,
+                             QInputDialog, QMenu, QLineEdit)
+from PyQt5.QtGui import QIcon
+from PyQtAds import QtAds
+
+from dockindockmanager import DockInDockManager
+from perspectiveactions import LoadPerspectiveAction, RemovePerspectiveAction
+
+
+class DockInDockWidget(QWidget):
+    def __init__(self, parent, perspectives_manager: 'PerspectivesManager', can_create_new_groups: bool = False, top_level_widget = None):
+        super().__init__(parent)
+        
+        if top_level_widget is not None:
+            self.__can_create_new_groups = top_level_widget.can_create_new_groups
+        else:
+            self.__can_create_new_groups = can_create_new_groups
+        self.__top_level_dock_widget = top_level_widget if top_level_widget else self
+        self.__perspectives_manager = perspectives_manager        
+        self.__new_perspective_default_name: str = ''
+        
+        layout = QVBoxLayout(self)
+        layout.setContentsMargins(0,0,0,0)
+        self.__mgr = DockInDockManager(self)
+        layout.addWidget(self.__mgr)
+        
+    def getManager(self) -> 'DockInDockManager':
+        return self.__mgr
+        
+    def getTopLevelDockWidget(self) -> 'DockInDockWidget':
+        return self.__top_level_dock_widget
+        
+    def canCreateNewGroups(self) -> bool:
+        return self.__can_create_new_groups
+        
+    def getPerspectivesManager(self) -> 'PerspectivesManager':
+        return self.__perspectives_manager
+        
+    def addTabWidget(self, widget: QWidget, name: str, after: QtAds.CDockAreaWidget, icon = QIcon()) -> QtAds.CDockAreaWidget:
+        for existing in self.getTopLevelDockWidget().getManager().allDockWidgets(True, True):
+            if existing[1].objectName() == name:
+                QMessageBox.critical(self, "Error", "Name '" + name + "' already in use")
+                return
+                
+        dock_widget = QtAds.CDockWidget(name)
+        dock_widget.setWidget(widget)
+        dock_widget.setIcon(icon)
+        
+        # Add the dock widget to the top dock widget area
+        return self.__mgr.addDockWidget(QtAds.CenterDockWidgetArea, dock_widget, after)
+        
+    def isTopLevel(self) -> bool:
+        return not self.objectName()
+        
+    def getGroupNameError(self, group_name: str) -> str:
+        if not group_name:
+            return "Group must have a non-empty name"
+            
+        dock_managers = self.__mgr.allManagers(True, True)
+        for mgr in dock_managers:
+            if mgr.getGroupName() == group_name:
+                return "Group name '" + group_name + "' already used"
+                
+        return ""
+        
+    def createGroup(self, group_name: str, insert_pos: QtAds.CDockAreaWidget, icon = QIcon()) -> 'DockInDockWidget':
+        error = self.getGroupNameError(group_name)
+        if error:
+            QMessageBox.critical(None, "Error", error)
+            return
+            
+        child = DockInDockWidget(self, self.__top_level_dock_widget, self.__perspectives_manager)
+        child.setObjectName(group_name)
+        
+        dock_widget = QtAds.CDockWidget(group_name)
+        dock_widget.setWidget(child)
+        dock_widget.setIcon(icon)
+        
+        insert_pos = self.__mgr.addDockWidget(QtAds.CenterDockWidgetArea, dock_widget, insert_pos)
+
+        return child, insert_pos
+        
+    def destroyGroup(self, widget_to_remove: 'DockInDockWidget') -> None:
+        top_level_widget = widget_to_remove.getTopLevelDockWidget()
+        
+        if top_level_widget and top_level_widget != widget_to_remove:
+            for dock_widget in widget_to_remove.getManager().getWidgetsInGUIOrder(): #don't use allDockWidgets to preserve sub-groups
+                MoveDockWidgetAction.move(dock_widget, top_level_widget.getManager())
+            assert not widget_to_remove.getManager().allDockWidgets(True, True)
+
+            # find widget's parent:
+            for dock_widget in top_level_widget.getManager().allDockWidgets(True, True):
+                if dockwidget[1].widget() == widget_to_remove:
+                    dockwidget[0].removeDockWidget(dockwidget[1])
+                    del dockwidget[1]
+                    # delete widgetToRemove; automatically deleted when dockWidget is deleted
+                    widget_to_remove = None
+                    break
+
+            assert widget_to_remove == None
+        else:
+            assert False
+            
+    def attachViewMenu(self, menu: QMenu) -> None:
+        menu.aboutToShow.connect(self.autoFillAttachedViewMenu)
+        
+    def autoFillAttachedViewMenu(self) -> None:
+        menu = self.sender()
+        
+        if menu:
+            menu.clear()
+            self.setupViewMenu(menu)
+        else:
+            assert False
+            
+    def setupViewMenu(self, menu):
+        dock_managers = self.__mgr.allManagers(True, True)
+        
+        has_perspectives_menu = False
+        if self.getTopLevelDockWidget() == self:
+            has_perspectives_menu = (self.__perspectives_manager != None)
+        else:
+            assert False
+            
+        organize = menu
+        if has_perspectives_menu:
+            organize = menu.addMenu("Organize")
+            
+        self.setupMenu(organize, dock_managers)
+        
+        if has_perspectives_menu:
+            perspectives = menu.addMenu("Perspectives")
+            self.fillPerspectivesMenu(perspectives)
+            
+    def setupMenu(self, menu: QMenu, move_to: 'list[DockInDockManager]') -> None:
+        self.__mgr.fillViewMenu(menu, move_to)
+        menu.addSeparator()
+        move_menu = menu.addMenu("Move")
+        self.__mgr.fillMoveMenu(move_menu, move_to)
+            
+    def fillPerspectivesMenu(self, menu: QMenu):
+        menu.addAction("Create perspective...", self.createPerspective)
+        perspectives_names = []
+        if self.__perspectives_manager:
+            perspectives_names = self.__perspectives_manager.perspectiveNames()
+            
+        if perspectives_names:
+            load = menu.addMenu("Load perspective")
+            for name in perspectives_names:
+                load.addAction(LoadPerspectiveAction(load, name, self))
+            remove = menu.addMenu("Remove perspective")
+            for name in perspectives_names:
+                remove.addAction(RemovePerspectiveAction(remove, name, self))
+                
+    def setNewPerspectiveDefaultName(default_name: str) -> None:
+        self.__new_perspective_default_name = default_name
+        
+    def createPerspective(self) -> None:
+        if not self.__perspectives_manager:
+            return
+            
+        name = self.__new_perspective_default_name
+        if self.__new_perspective_default_name:
+            index = 2
+            while name in self.__perspectives_manager.perspectiveNames():
+                name = f"{self.__new_perspective_default_name}({index})"
+                index += 1
+                
+        while True:
+            name, ok = QInputDialog.getText(None, "Create perspective", "Enter perspective name", QLineEdit.Normal, name)
+            if ok:
+                if not name:
+                    QMessageBox.critical(None, "Error", "Perspective name cannot be empty")
+                    continue
+                elif name in self.__perspectives_manager.perspectiveNames():
+                    if QMessageBox.critical(None, "Error", f"Perspective '{name}' already exists, overwrite it?", QMessageBox.Yes | QMessageBox.No, QMessageBox.No) == QMessageBox.No:
+                        continue
+                    
+                self.__perspectives_manager.addPerspective(name, self)
+                break
+            else:
+                break
+                
+    def dumpStatus(self, echo: callable = print, widget: QtAds.CDockWidget = None, tab: str = '', suffix: str = '') -> str:
+        if widget is not None:
+            as_mgr = DockInDockManager.dockInAManager(widget)
+            if as_mgr:
+                as_mgr.parent().dumpStatus(tab=tab)
+            else:
+                echo(tab + widget.objectName() + suffix)
+        else:
+            echo(tab + "Group: " + self.getManager().getGroupName())
+            tab += "   "
+            visible_widgets = set()
+            for widget in self.getManager().getWidgetsInGUIOrder():
+                visible_widgets.add(widget)
+                self.dumpStatus(widget=widget, tab=tab)
+                
+            for closed in self.getManager().dockWidgetsMap().values():
+                if not closed in visible_widgets:
+                    self.dumpStatus(widget=closed, tab=tab, suffix=" (closed)")

examples/dockindock/dockindockmanager.cpp

@@ -0,0 +1,334 @@
+#include "dockindockmanager.h"
+#include "dockindock.h"
+
+#include "DockAreaWidget.h"
+
+#include <QMenu>
+#include <QInputDialog>
+#include <QSettings>
+#include <QMessageBox>
+
+#include <assert.h>
+
+using namespace QtAdsUtl;
+
+/////////////////////////////////////
+// DockInDockManager
+/////////////////////////////////////
+DockInDockManager::DockInDockManager( DockInDockWidget& parent ) :
+    baseClass( &parent ),
+    m_parent( parent )
+{
+
+}
+
+DockInDockManager::~DockInDockManager()
+{
+
+}
+
+void DockInDockManager::fillViewMenu( QMenu* menu, const std::vector<DockInDockManager*>& moveTo )
+{
+    auto widgetsMap = dockWidgetsMap();
+    for ( auto iter = widgetsMap.begin(); iter != widgetsMap.end(); ++iter )
+    {
+        auto widget = iter.value()->widget();
+        auto action = iter.value()->toggleViewAction();
+
+        DockInDockWidget* asMgr = dynamic_cast<DockInDockWidget*>( widget );
+        if ( asMgr )
+        {
+            auto subMenu = menu->addMenu( iter.key() );
+
+            subMenu->addAction( action );
+            subMenu->addSeparator();
+
+            asMgr->setupMenu( subMenu, moveTo );
+        }
+        else
+        {
+            menu->addAction(action);
+        }
+    }
+
+    if ( parent().canCreateNewGroups() )
+    {
+        // see how this works, to create it in the right place, 
+        // and also to have load perspective work when some groups are missing
+        menu->addSeparator();
+        menu->addAction( new QtAdsUtl::CreateChildDockAction( m_parent, menu ) );
+
+        if ( parent().getTopLevelDockWidget()->getManager() != this )
+            menu->addAction( new QtAdsUtl::DestroyGroupAction( &m_parent, menu ) );
+    }
+}
+
+void DockInDockManager::fillMoveMenu( QMenu* menu, const std::vector<DockInDockManager*>& moveTo )
+{
+    auto widgetsMap = dockWidgetsMap();
+    for ( auto iter = widgetsMap.begin(); iter != widgetsMap.end(); ++iter )
+    {
+        auto subMenu = menu->addMenu( iter.key() );
+
+        for ( auto mgr : moveTo )
+        {
+            // iterate over all possible target managers
+            if ( mgr == this )
+            {
+                // if dock is already in mgr, no reason to move it there
+            }
+            else if ( mgr == dockInAManager( iter.value() ) )
+            {
+                // if target is the group itself, can't move it there, would make no sense
+            }
+            else
+            {
+                subMenu->addAction( new MoveDockWidgetAction( iter.value(), mgr, subMenu ) );
+            }
+        }
+    }
+}
+
+void DockInDockManager::addPerspectiveRec( const QString& name )
+{
+    std::vector<DockInDockManager*> managers = allManagers( true, true );
+
+    for ( auto child : managers )
+        child->addPerspective( name );
+}
+
+void DockInDockManager::openPerspectiveRec( const QString& name )
+{
+    std::vector<DockInDockManager*> managers = allManagers( true, true );
+
+    for ( auto child : managers )
+        child->openPerspective( name );
+}
+
+QString DockInDockManager::getGroupName()
+{
+    return parent().objectName();
+}
+
+#define CHILD_PREFIX QString("Child-")
+QString DockInDockManager::getPersistGroupName()
+{
+    QString group = "Top";
+    if ( !getGroupName().isEmpty() )
+        group = CHILD_PREFIX + getGroupName();
+    return group;
+}
+
+QString DockInDockManager::getGroupNameFromPersistGroupName( QString persistGroupName )
+{
+    if ( persistGroupName.startsWith( CHILD_PREFIX ) )
+    {
+        persistGroupName = persistGroupName.mid( CHILD_PREFIX.size() );
+    }
+    else
+    {
+        assert( false );
+    }
+    return persistGroupName;
+}
+
+void DockInDockManager::loadPerspectivesRec(QSettings& Settings)
+{
+    std::vector<DockInDockManager*> children = allManagers( true, true );
+
+    for ( auto mgr : children )
+    {
+        Settings.beginGroup(mgr->getPersistGroupName());
+        mgr->loadPerspectives( Settings );
+        Settings.endGroup();
+    }
+}
+
+void DockInDockManager::savePerspectivesRec(QSettings& Settings) const
+{
+    std::vector<DockInDockManager*> children = allManagers( true, true );
+
+    for ( auto mgr : children )
+    {
+        Settings.beginGroup(mgr->getPersistGroupName());
+        mgr->savePerspectives( Settings );
+        Settings.endGroup();
+    }
+}
+
+void DockInDockManager::removePerspectivesRec()
+{
+    std::vector<DockInDockManager*> managers = allManagers( true, true );
+
+    for ( auto child : managers )
+        child->removePerspectives( child->perspectiveNames() );
+}
+
+DockInDockManager* DockInDockManager::dockInAManager( ads::CDockWidget* widget )
+{
+    DockInDockWidget* dockWidget = widget ? dynamic_cast<DockInDockWidget*>( widget->widget() ) : NULL;
+    return ( dockWidget ) ? dockWidget->getManager() : NULL;
+}
+
+void DockInDockManager::childManagers( std::vector<DockInDockManager*>& managers, bool rec ) const
+{
+    auto widgets = getWidgetsInGUIOrder();
+    for ( auto widget : widgets )
+    {
+        DockInDockManager* asMgr = dockInAManager( widget );
+        if ( asMgr )
+        {
+            managers.push_back( asMgr );
+            if ( rec )
+                asMgr->childManagers( managers, rec );
+        }
+    }
+}
+
+std::vector<DockInDockManager*> DockInDockManager::allManagers( bool includeThis, bool rec ) const
+{
+    std::vector<DockInDockManager*> managers;
+    if ( includeThis )
+        managers.push_back( const_cast<DockInDockManager*>(this) );
+    childManagers( managers, rec );
+    return managers;
+}
+
+std::vector<std::pair<DockInDockManager*,ads::CDockWidget*>> DockInDockManager::allDockWidgets( bool includeThis, bool rec ) const
+{
+    std::vector<std::pair<DockInDockManager*,ads::CDockWidget*>> widgets;
+    for ( auto mgr : allManagers( includeThis, rec ) )
+    {
+        for ( auto widget : mgr->getWidgetsInGUIOrder() )
+            widgets.push_back( std::make_pair(mgr, widget) );
+    }
+    return widgets;
+}
+
+QMap<QString,QStringList> DockInDockManager::getGroupContents()
+{
+    QMap<QString,QStringList> result;
+    std::vector<DockInDockManager*> managers = allManagers( true, true );
+    for ( auto mgr : managers )
+    {
+        result[mgr->getPersistGroupName()] = mgr->dockWidgetsMap().keys();
+    }
+    return result;
+}
+
+ads::CDockAreaWidget* DockInDockManager::getInsertDefaultPos()
+{
+    ads::CDockAreaWidget* defaultPos = NULL;
+    if ( dockAreaCount() != 0 )
+        defaultPos = dockArea(dockAreaCount()-1);
+    return defaultPos;
+}
+
+std::vector<ads::CDockWidget*> DockInDockManager::getWidgetsInGUIOrder() const
+{
+    std::vector<ads::CDockWidget*> result;
+    result.reserve( dockWidgetsMap().size() );
+    for ( int i = 0; i != dockAreaCount(); ++i )
+    {
+        for ( auto widget : dockArea(i)->dockWidgets() )
+            result.push_back( widget );
+    }
+    return result;
+}
+
+/////////////////////////////////////
+// CreateChildDockAction
+/////////////////////////////////////
+CreateChildDockAction::CreateChildDockAction( DockInDockWidget& dockInDock, QMenu* menu ) :
+    QAction("New group...", menu),
+    m_dockInDock( dockInDock )
+{
+    connect( this, SIGNAL(triggered()), this, SLOT(createGroup()) );
+}
+
+void CreateChildDockAction::createGroup()
+{
+    QString name = "";
+    while ( true )
+    {
+        bool ok = false;
+        name = QInputDialog::getText( NULL, this->text(), "Enter group name", QLineEdit::Normal, name, &ok );
+        if ( ok )
+        {
+            QString error = "";
+            if ( m_dockInDock.getTopLevelDockWidget() )
+                error = m_dockInDock.getTopLevelDockWidget()->getGroupNameError( name );
+            else
+                assert( false );
+
+            if ( error.isEmpty() )
+            {
+                ads::CDockAreaWidget* insertPos = NULL;
+                m_dockInDock.createGroup( name, insertPos );
+                break;
+            }
+            else
+            {
+                QMessageBox::critical( NULL, "Error", error );
+                continue;
+            }
+        }
+        else
+        {
+            break;
+        }
+    }
+}
+
+/////////////////////////////////////
+// DestroyGroupAction
+/////////////////////////////////////
+DestroyGroupAction::DestroyGroupAction( DockInDockWidget* widget, QMenu* menu ) :
+    QAction("Destroy " + widget->getManager()->getGroupName(), menu),
+    m_widget( widget )
+{
+    connect( this, SIGNAL(triggered()), this, SLOT(destroyGroup()) );
+}
+
+void DestroyGroupAction::destroyGroup()
+{
+    m_widget->getTopLevelDockWidget()->destroyGroup( m_widget );
+}
+
+
+/////////////////////////////////////
+// MoveDockWidgetAction
+/////////////////////////////////////
+MoveDockWidgetAction::MoveDockWidgetAction( ads::CDockWidget* widget, DockInDockManager* moveTo, QMenu* menu ) :
+    QAction(menu),
+    m_widget( widget ),
+    m_moveTo( moveTo )
+{
+    if ( moveTo->parent().isTopLevel() )
+    {
+        setText( "To top" );
+    }
+    else
+    {
+        setText( "To " + moveTo->parent().objectName() );
+    }
+    connect( this, SIGNAL(triggered()), this, SLOT(move()) );
+}
+
+void MoveDockWidgetAction::move()
+{
+    move( m_widget, m_moveTo );
+}
+
+void MoveDockWidgetAction::move( ads::CDockWidget* widget, DockInDockManager* moveTo )
+{
+    if ( widget && moveTo )
+    {
+        widget->dockManager()->removeDockWidget( widget );
+        moveTo->addDockWidget(ads::CenterDockWidgetArea, widget, moveTo->getInsertDefaultPos());
+    }
+    else
+    {
+        assert( false );
+    }
+}

examples/dockindock/dockindockmanager.h

@@ -0,0 +1,96 @@
+#pragma once
+
+#include "DockManager.h"
+
+#include <QAction>
+#include <QMap>
+
+namespace QtAdsUtl
+{
+
+class DockInDockWidget;
+class DockInDockManager : public ads::CDockManager
+{
+    Q_OBJECT
+
+    typedef ads::CDockManager baseClass;
+
+public:
+    DockInDockManager( DockInDockWidget& parent );
+    ~DockInDockManager() override; 
+
+    void fillViewMenu( QMenu* menu, const std::vector<DockInDockManager*>& moveTo );
+    void fillMoveMenu( QMenu* menu, const std::vector<DockInDockManager*>& moveTo );
+
+    void addPerspectiveRec( const QString& name );
+    void openPerspectiveRec( const QString& name );
+    void removePerspectivesRec();
+    void loadPerspectivesRec(QSettings& Settings);
+    void savePerspectivesRec(QSettings& Settings) const;
+
+    static DockInDockManager* dockInAManager( ads::CDockWidget* widget );
+
+    inline DockInDockWidget& parent() { return m_parent; }
+
+    void childManagers( std::vector<DockInDockManager*>& managers, bool rec ) const;
+    std::vector<DockInDockManager*> allManagers( bool includeThis, bool rec ) const;
+    std::vector<std::pair<DockInDockManager*,ads::CDockWidget*>> allDockWidgets( bool includeThis, bool rec ) const;
+
+    QString getGroupName();
+    QString getPersistGroupName();
+    static QString getGroupNameFromPersistGroupName( QString persistGroupName );
+
+    QMap<QString,QStringList> getGroupContents();
+
+    ads::CDockAreaWidget* getInsertDefaultPos();
+
+    std::vector<ads::CDockWidget*> getWidgetsInGUIOrder() const;
+
+private:
+    DockInDockWidget& m_parent;
+};
+
+class CreateChildDockAction : public QAction
+{
+    Q_OBJECT
+public:
+    CreateChildDockAction( DockInDockWidget& dockInDock, QMenu* menu );
+
+public slots:
+    void createGroup();
+
+private:
+    DockInDockWidget& m_dockInDock;
+};
+
+class DestroyGroupAction : public QAction
+{
+    Q_OBJECT
+public:
+    DestroyGroupAction( DockInDockWidget* widget, QMenu* menu );
+
+public slots:
+    void destroyGroup();
+
+private:
+    DockInDockWidget* m_widget;
+};
+
+class MoveDockWidgetAction : public QAction
+{
+    Q_OBJECT
+public:
+    MoveDockWidgetAction( ads::CDockWidget* widget, DockInDockManager* moveTo, QMenu* menu );
+
+    static void move( ads::CDockWidget* widget, DockInDockManager* moveTo );
+
+public slots:
+    void move();
+
+private:
+    ads::CDockWidget* m_widget;
+    DockInDockManager* m_moveTo;
+};
+
+}
+

examples/dockindock/dockindockmanager.py

@@ -0,0 +1,214 @@
+from PyQt5.QtWidgets import QAction, QMenu, QInputDialog, QLineEdit
+from PyQt5.QtCore import QSettings
+
+from PyQtAds import QtAds
+
+CHILD_PREFIX = "Child-"
+
+class DockInDockManager(QtAds.CDockManager):
+    def __init__(self, parent: 'DockInDockWidget'):
+        super().__init__()
+        self.__parent = parent
+
+    def parent(self) -> 'DockInDockWidget':
+        return self.__parent
+    
+    def fillViewMenu(self, menu: QMenu, move_to: 'dict[DockInDockManager]') -> None:
+        from dockindock import DockInDockWidget # Prevent cyclic import
+        
+        widgets_map = self.dockWidgetsMap()
+        for key, value in widgets_map.items():
+            widget = value.widget()
+            action = value.toggleViewAction()
+            
+            if isinstance(widget, DockInDockWidget):
+                sub_menu = menu.addMenu(key)
+                
+                sub_menu.addAction(action)
+                sub_menu.addSeparator()
+                
+                widget.setupMenu(sub_menu, move_to)
+            else:
+                menu.addAction(action)
+                
+        if self.parent().canCreateNewGroups():
+            # see how this works, to create it in the right place, 
+            # and also to have load perspective work when some groups are missing
+            menu.addSeparator()
+            menu.addAction(CreateChildDockAction(self.__parent, menu))
+
+            if self.parent().getTopLevelDockWidget().getManager() != self:
+                menu.addAction(DestroyGroupAction( self.parent, menu))
+                
+    def fillMoveMenu(self, menu: QMenu, move_to: 'list[DockInDockManager]') -> None:
+        widgets_map = self.dockWidgetsMap()
+        for key, value in widgets_map.items():
+            sub_menu = menu.addMenu(key)
+            
+            for mgr in move_to:
+                # iterate over all possible target managers
+                if mgr == self:
+                    pass # if dock is already in mgr, no reason to move it there
+                elif mgr == DockInDockManager.dockInAManager(value):
+                    pass # if target is the group itself, can't move it there, would make no sense
+                else:
+                    sub_menu.addAction(MoveDockWidgetAction(value, mgr, sub_menu))
+    
+    def addPerspectiveRec(self, name: str) -> None:
+        managers = self.allManagers(True, True)
+        
+        for child in managers:
+            child.addPerspective(name)
+            
+    def openPerspectiveRec(self, name: str) -> None:
+        managers = self.allManagers(True, True)
+        
+        for child in managers:
+            child.openPerspective(name)
+            
+    def getGroupName(self) -> str:
+        return self.parent().objectName()
+        
+    def getPersistGroupName(self) -> str:
+        group = "Top"
+        if self.getGroupName():
+            group = CHILD_PREFIX + self.getGroupName()
+        return group
+        
+    def getGroupNameFromPersistGroupName(self, persist_group_name) -> str:
+        if persist_group_name.startswith(CHILD_PREFIX):
+            persist_group_name = persist_group_name[len(CHILD_PREFIX):]
+        else:
+            assert False
+        return persist_group_name
+        
+    def loadPerspectivesRec(self, settings: QSettings) -> None:
+        children = self.allManagers(True, True)
+        
+        for mgr in children:
+            settings.beginGroup(mgr.getPersistGroupName())
+            mgr.loadPerspectives(settings)
+            settings.endGroup()
+            
+    def savePerspectivesRec(self, settings: QSettings) -> None:
+        children = self.allManagers(True, True)
+        
+        for mgr in children:
+            settings.beginGroup(mgr.getPersistGroupName())
+            mgr.savePerspectives(settings)
+            settings.endGroup()
+            
+    def removePerspectivesRec(self, settings: QSettings) -> None:
+        children = self.allManagers(True, True)
+        
+        for mgr in children:
+            child.removePerspectives(child.perspectiveNames())
+            
+    @staticmethod
+    def dockInAManager(widget) -> 'DockInDockManager':
+        from dockindock import DockInDockWidget # Prevent cyclic import
+        
+        dock_widget =  widget.widget() if widget else None
+        return dock_widget.getManager() if isinstance(dock_widget, DockInDockWidget) else None
+        
+    def childManagers(self, managers: 'list[DockInDockManager]', rec: bool) -> None:
+        widgets = self.getWidgetsInGUIOrder()
+        for widget in widgets:
+            as_mgr = DockInDockManager.dockInAManager(widget)
+            if as_mgr:
+                managers.append(as_mgr)
+                if rec:
+                    as_mgr.childManagers(managers, rec)
+                    
+    def allManagers(self, include_self: bool, rec: bool) -> 'list[DockInDockManager]':
+        managers = []
+        if include_self:
+            managers.append(self)
+        self.childManagers(managers, rec)
+        return managers
+        
+    def allDockWidgets(self, include_self: bool, rec: bool) -> 'list[tuple[DockInDockManager, QtAds.CDockWidget]]':
+        widgets = []
+        for mgr in self.allManagers(include_self, rec):
+            for widget in mgr.getWidgetsInGUIOrder():
+                widgets.append((mgr, widget))
+        return widgets
+        
+    def getGroupContents(self) -> 'dict[str, list[str]]':
+        result = {}
+        managers = self.allManagers(True, True)
+        for mgr in managers:
+            result[mgr.getPersistGroupName()] = mgr.dockWidgetsMap().keys()
+        return result
+        
+    def getInsertDefaultPos(self) -> QtAds.CDockAreaWidget:
+        default_pos = None
+        if self.dockAreaCount() != 0:
+            default_pos = self.dockArea(self.dockAreaCount()-1)
+        return default_pos
+        
+    def getWidgetsInGUIOrder(self) -> 'list[QtAds.CDockWidget]':
+        result = []
+        for i in range(self.dockAreaCount()):
+            for widget in self.dockArea(i).dockWidgets():
+                result.append(widget)
+        return result
+        
+    
+class CreateChildDockAction(QAction):
+    def __init__(self, dock_in_dock: 'DockInDockWidget', menu: QMenu):
+        super().__init__("New group...", menu)
+        self.__dock_in_dock = dock_in_dock
+        self.triggered.connect(self.createGroup)
+        
+    def createGroup(self) -> None:
+        name = ""
+        while True:
+            name, ok = QInputDialog.getText(None, self.text(), "Enter group name", QLineEdit.Normal, name)
+            if ok:
+                error = ""
+                if self.__dock_in_dock.getTopLevelDockWidget():
+                    error = self.__dock_in_dock.getTopLevelDockWidget().getGroupNameError(name)
+                else:
+                    assert False
+                    
+                if not error:
+                    self.__dock_in_dock.createGroup(name, None)
+                    break
+                else:
+                    QMessageBox.critical(None, "Error", error)
+                    continue
+            else:
+                break
+        
+class DestroyGroupAction(QAction):
+    def __init__(self, widget: 'DockInDockWidget', menu: QMenu):
+        super().__init__("Destroy" + widget.getManager().getGroupName(), menu)
+        self.__widget = widget
+        self.triggered.connect(self.destroyGroup)
+        
+    def destroyGroup(self) -> None:
+        self.__widget.getTopLevelDockWidget().destroyGroup(self.__widget)
+        
+        
+class MoveDockWidgetAction(QAction):
+    def __init__(self, widget: 'DockInDockWidget', move_to: DockInDockManager, menu: QMenu):
+        super().__init__(menu)
+        self.__widget = widget
+        self.__move_to = move_to
+        
+        if move_to.parent().isTopLevel():
+            self.setText("To top")
+        else:
+            self.setText(f"To {move_to.parent().objectName()}")
+        self.triggered.connect(self._move)
+        
+    def _move(self) -> None:
+        self.move(self.__widget, self.__move_to)
+        
+    def move(self, widget: QtAds.CDockWidget, move_to: QtAds.CDockManager) -> None:
+        if widget and move_to:
+            widget.dockManager().removeDockWidget(widget)
+            move_to.addDockWidget(QtAds.CenterDockWidgetArea, widget, move_to.getInsertDefaultPos())
+        else:
+            assert False

examples/dockindock/main.cpp

@@ -0,0 +1,11 @@
+#include <QApplication>
+#include "../../examples/simple/MainWindow.h"
+
+int main(int argc, char *argv[])
+{
+    QApplication a(argc, argv);
+    MainWindow w;
+    w.show();
+
+    return a.exec();
+}

examples/dockindock/main.py

@@ -0,0 +1,72 @@
+import sys
+import os
+import atexit
+
+from PyQt5.QtWidgets import QApplication, QMainWindow, QLabel
+from PyQt5.QtCore import Qt
+from PyQtAds import QtAds
+
+from perspectives import PerspectivesManager
+from dockindock import DockInDockWidget
+    
+class MainWindow(QMainWindow):
+    def __init__(self, parent=None):
+        super().__init__(parent)
+        
+        self.perspectives_manager = PerspectivesManager("persist")
+        self.resize(400, 400)
+        self.dock_manager = DockInDockWidget(self, self.perspectives_manager, can_create_new_groups=True)
+        self.setCentralWidget(self.dock_manager)
+        self.dock_manager.attachViewMenu(self.menuBar().addMenu("View"))
+
+        previous_dock_widget = None
+        for i in range(3):
+            l = QLabel()
+            l.setWordWrap(True)
+            l.setAlignment(Qt.AlignTop | Qt.AlignLeft)
+            l.setText("Lorem ipsum dolor sit amet, consectetuer adipiscing elit. ")
+            
+            previous_dock_widget = self.dock_manager.addTabWidget(l, f"Top label {i}", previous_dock_widget)
+            
+        last_top_level_dock = previous_dock_widget
+        
+        for j in range(2):
+            group_manager, _ = self.dock_manager.createGroup(f"Group {j}", last_top_level_dock)
+            
+            previous_dock_widget = None
+            
+            for i in range(3):
+                # Create example content label - this can be any application specific widget
+                l = QLabel()
+                l.setWordWrap(True)
+                l.setAlignment(Qt.AlignTop | Qt.AlignLeft)
+                l.setText("Lorem ipsum dolor sit amet, consectetuer adipiscing elit. ")
+
+                previous_dock_widget = group_manager.addTabWidget(l, f"ZInner {j}/{i}", previous_dock_widget)
+                
+            # create sub-group
+            sub_group, _ = group_manager.createGroup(f"SubGroup {j}", previous_dock_widget)
+            previous_dock_widget = None
+            for i in range(3):
+                # Create example content label - this can be any application specific widget
+                l = QLabel()
+                l.setWordWrap(True)
+                l.setAlignment(Qt.AlignTop | Qt.AlignLeft)
+                l.setText("Lorem ipsum dolor sit amet, consectetuer adipiscing elit. ")
+
+                previous_dock_widget = sub_group.addTabWidget(l, f"SubInner {j}/{i}", previous_dock_widget)
+                
+        self.perspectives_manager.loadPerspectives()
+        
+        atexit.register(self.cleanup)
+        
+    def cleanup(self):
+        self.perspectives_manager.savePerspectives()
+
+        
+if __name__ == '__main__':
+    app = QApplication(sys.argv)
+    
+    w = MainWindow()
+    w.show()
+    app.exec_()

examples/dockindock/mainframe.cpp

@@ -0,0 +1,76 @@
+#include "mainframe.h"
+
+#include "dockindock.h"
+#include "perspectives.h"
+
+#include <QLabel>
+#include <QMenuBar>
+#include <QMessageBox>
+#include <QSettings>
+
+MainWindow::MainWindow(QWidget *parent) :
+    QMainWindow(parent),
+    m_perspectivesManager( new QtAdsUtl::PerspectivesManager( "persist" ) )
+{
+    resize( 400, 400 );
+
+    setCentralWidget( m_dockManager = new QtAdsUtl::DockInDockWidget(this,true,m_perspectivesManager.get()) );
+
+    m_dockManager->attachViewMenu( menuBar()->addMenu( "View" ) );
+
+    ads::CDockAreaWidget* previousDockWidget = NULL;
+    for ( int i = 0; i != 3; ++i )
+    {
+        // Create example content label - this can be any application specific
+        // widget
+        QLabel* l = new QLabel();
+        l->setWordWrap(true);
+        l->setAlignment(Qt::AlignTop | Qt::AlignLeft);
+        l->setText("Lorem ipsum dolor sit amet, consectetuer adipiscing elit. ");
+
+        previousDockWidget = m_dockManager->addTabWidget( l, "Top label " + QString::number(i), previousDockWidget );
+    }
+
+    auto lastTopLevelDock = previousDockWidget;
+
+    for ( int j = 0; j != 2; ++j )
+    {
+        QtAdsUtl::DockInDockWidget* groupManager = m_dockManager->createGroup( "Group " + QString::number(j), lastTopLevelDock );
+
+        previousDockWidget = NULL;
+        for ( int i = 0; i != 3; ++i )
+        {
+            // Create example content label - this can be any application specific
+            // widget
+            QLabel* l = new QLabel();
+            l->setWordWrap(true);
+            l->setAlignment(Qt::AlignTop | Qt::AlignLeft);
+            l->setText("Lorem ipsum dolor sit amet, consectetuer adipiscing elit. ");
+
+            previousDockWidget = groupManager->addTabWidget( l, "ZInner " + QString::number(j) + "/" + QString::number(i), previousDockWidget );
+        }
+
+        // create sub-group
+        auto subGroup = groupManager->createGroup( "SubGroup " + QString::number(j), previousDockWidget );
+        previousDockWidget = NULL;
+        for ( int i = 0; i != 3; ++i )
+        {
+            // Create example content label - this can be any application specific
+            // widget
+            QLabel* l = new QLabel();
+            l->setWordWrap(true);
+            l->setAlignment(Qt::AlignTop | Qt::AlignLeft);
+            l->setText("Lorem ipsum dolor sit amet, consectetuer adipiscing elit. ");
+
+            previousDockWidget = subGroup->addTabWidget( l, "SubInner " + QString::number(j) + "/" + QString::number(i), previousDockWidget );
+        }
+    }
+
+    m_perspectivesManager->loadPerspectives();
+}
+
+MainWindow::~MainWindow()
+{
+    m_perspectivesManager->savePerspectives();
+}
+

examples/dockindock/mainframe.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <QMainWindow>
+#include <QAction>
+#include <QSettings>
+
+#include <memory>
+namespace QtAdsUtl
+{
+    class DockInDockWidget;
+    class PerspectivesManager;
+}
+
+class MainWindow : public QMainWindow
+{
+    Q_OBJECT
+
+public:
+    explicit MainWindow(QWidget *parent = 0);
+    ~MainWindow();
+
+    QtAdsUtl::DockInDockWidget* m_dockManager;
+    std::unique_ptr<QtAdsUtl::PerspectivesManager> m_perspectivesManager;
+};
+
+
+
+
+
+

examples/dockindock/perspectiveactions.cpp

@@ -0,0 +1,39 @@
+#include "perspectiveactions.h"
+#include "dockindock.h"
+#include "perspectives.h"
+
+#include <QMenu>
+
+using namespace QtAdsUtl;
+
+//////////////////////////////
+// LoadPerspectiveAction
+//////////////////////////////
+LoadPerspectiveAction::LoadPerspectiveAction( QMenu* parent, const QString& name, QtAdsUtl::DockInDockWidget& dockManager ) :
+    QAction( name, parent ),
+    name( name ),
+    dockManager( dockManager )
+{
+    connect( this, SIGNAL(triggered()), this, SLOT(load()) );
+}
+
+void LoadPerspectiveAction::load()
+{
+    dockManager.getPerspectivesManager()->openPerspective( name, dockManager );
+}
+
+//////////////////////////////
+// RemovePerspectiveAction
+//////////////////////////////
+RemovePerspectiveAction::RemovePerspectiveAction( QMenu* parent, const QString& name, QtAdsUtl::DockInDockWidget& dockManager ) :
+    QAction( name, parent ),
+    name( name ),
+    dockManager( dockManager )
+{
+    connect( this, SIGNAL(triggered()), this, SLOT(remove()) );
+}
+
+void RemovePerspectiveAction::remove()
+{
+    dockManager.getPerspectivesManager()->removePerspective( name );
+}

examples/dockindock/perspectiveactions.h

@@ -0,0 +1,38 @@
+#pragma once
+
+#include <QAction>
+
+namespace QtAdsUtl
+{
+
+class DockInDockWidget;
+class LoadPerspectiveAction : public QAction
+{
+    Q_OBJECT
+public:
+    LoadPerspectiveAction( QMenu* parent, const QString& name, QtAdsUtl::DockInDockWidget& dockManager );
+
+public slots:
+    void load();
+
+private:
+    QString name;
+    QtAdsUtl::DockInDockWidget& dockManager;
+};
+
+class RemovePerspectiveAction : public QAction
+{
+    Q_OBJECT
+public:
+    RemovePerspectiveAction( QMenu* parent, const QString& name, QtAdsUtl::DockInDockWidget& dockManager );
+
+public slots:
+    void remove();
+
+private:
+    QString name;
+    QtAdsUtl::DockInDockWidget& dockManager;
+};
+
+}
+

examples/dockindock/perspectiveactions.py

@@ -0,0 +1,25 @@
+from PyQt5.QtWidgets import QAction, QMenu
+
+
+class LoadPerspectiveAction(QAction):
+    def __init__(self, parent: QMenu, name: str, dock_manager: 'DockInDockWidget'):
+        super().__init__(name, parent)
+        self.name = name
+        self.dock_manager = dock_manager
+        
+        self.triggered.connect(self.load)
+        
+    def load(self):
+        self.dock_manager.getPerspectivesManager().openPerspective(self.name, self.dock_manager)
+        
+        
+class RemovePerspectiveAction(QAction):
+    def __init__(self, parent: QMenu, name: str, dock_manager: 'DockInDockWidget'):
+        super().__init__(name, parent)
+        self.name = name
+        self.dock_manager = dock_manager
+        
+        self.triggered.connect(self.remove)
+        
+    def remove(self):
+        self.dock_manager.getPerspectivesManager().removePerspective(self.name)

examples/dockindock/perspectives.cpp

@@ -0,0 +1,278 @@
+#include "perspectives.h"
+#include "dockindock.h"
+#include "dockindockmanager.h"
+
+#include <QSettings>
+#include <QFile>
+#include <QDir>
+
+#include <assert.h>
+
+#define GROUP_PREFIX QString("Group")
+
+using namespace QtAdsUtl;
+
+PerspectivesManager::PerspectivesManager( const QString& perspectivesFolder ) :
+    m_perspectivesFolder( perspectivesFolder )
+{
+    
+}
+
+PerspectivesManager::~PerspectivesManager()
+{
+    // remove temp files:
+    for ( auto perspective : m_perspectives )
+    {
+        QString fileName = perspective.settings->fileName();
+        perspective.settings.reset();
+        QFile::remove(fileName);
+    }
+}
+
+
+QStringList PerspectivesManager::perspectiveNames() const
+{
+    return m_perspectives.keys();
+}
+
+void PerspectivesManager::addPerspective( const QString& name, DockInDockWidget& widget )
+{
+    if ( !m_perspectivesFolder.isEmpty() )
+    {
+        m_perspectives[name].settings = getSettingsObject( getSettingsFileName( name, true ) );
+        m_perspectives[name].groups = widget.getManager()->getGroupContents();
+
+        // save perspective internally
+        widget.getManager()->addPerspectiveRec( name );
+        // store it in QSettings object
+        widget.getManager()->savePerspectivesRec( *(m_perspectives[name].settings) );
+        // remove internal perspectives
+        widget.getManager()->removePerspectives( widget.getManager()->perspectiveNames() );
+    }
+    else
+    {
+        assert( false );
+    }
+
+    emit perspectivesListChanged();
+}
+
+
+ads::CDockWidget* findWidget( QString name, const std::vector<DockInDockManager*>& managers )
+{
+    for ( auto mgr : managers )
+    {
+        auto widget = mgr->findDockWidget(name);
+        if ( widget )
+            return widget;
+    }
+    return NULL;
+}
+
+void PerspectivesManager::openPerspective( const QString& name, DockInDockWidget& widget )
+{
+    assert( widget.getTopLevelDockWidget() == &widget );
+
+    if ( !m_perspectivesFolder.isEmpty() )
+    {
+        if ( m_perspectives.contains( name ) )
+        {
+            emit openingPerspective();
+
+            if ( widget.canCreateNewGroups() )
+            {
+                auto curGroups = widget.getManager()->allManagers(true,true);
+                for ( auto group : m_perspectives[name].groups.keys() )
+                {
+                    bool found = false;
+                    for ( auto curgroup : curGroups )
+                    {
+                        if ( curgroup->getPersistGroupName() == group )
+                        {
+                            found = true;
+                            break;
+                        }
+                    }
+                    if ( !found )
+                    {
+                        group = DockInDockManager::getGroupNameFromPersistGroupName( group );
+
+                        // restore group in file but not in GUI yet
+                        ads::CDockAreaWidget* insertPos = NULL;
+                        widget.createGroup( group, insertPos );
+                    }
+                }
+
+                curGroups = widget.getManager()->allManagers(false,true);
+                for ( auto curgroup : curGroups )
+                {
+                    if ( !m_perspectives[name].groups.keys().contains( curgroup->getPersistGroupName() ) )
+                    {
+                        widget.destroyGroup( &curgroup->parent() );
+                    }
+                }
+            }
+
+            auto managers = widget.getManager()->allManagers(true,true);
+            for ( auto group : m_perspectives[name].groups.keys() )
+            {
+                for ( auto mgr : managers )
+                {
+                    if ( mgr->getPersistGroupName() == group )
+                    {
+                        for ( QString widgetName : m_perspectives[name].groups[group] )
+                        {
+                            ads::CDockWidget* widget = findWidget( widgetName, { mgr } );
+                            if ( widget )
+                            {
+                                // OK, widget is already in the good manager!
+                            }
+                            else
+                            {
+                                widget = findWidget( widgetName, managers );
+                                if ( widget )
+                                {
+                                    // move dock widget in the same group as it used to be when perspective was saved
+                                    // this guarantee load/open perspectives will work smartly
+                                    MoveDockWidgetAction::move( widget, mgr );
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+
+            // internally load perspectives from QSettings
+            widget.getManager()->loadPerspectivesRec( *(m_perspectives[name].settings) );
+            // load perspective (update GUI)
+            widget.getManager()->openPerspectiveRec( name );
+            // remove internal perspectives
+            widget.getManager()->removePerspectives( widget.getManager()->perspectiveNames() );
+
+            emit openedPerspective();
+        }
+    }
+    else
+    {
+        assert( false );
+    }
+}
+
+void PerspectivesManager::removePerspectives()
+{
+    m_perspectives.clear();
+    emit perspectivesListChanged();
+}
+
+void PerspectivesManager::removePerspective( const QString& name )
+{
+    m_perspectives.remove( name );
+    emit perspectivesListChanged();
+}
+
+QString PerspectivesManager::getSettingsFileName( const QString& perspective, bool temp ) const
+{
+    auto name = ( perspective.isEmpty() ) ? "perspectives.ini" : "perspective_" + perspective + (temp?".tmp":".ini");
+
+    return m_perspectivesFolder + "/" + name;
+}
+
+std::shared_ptr<QSettings> PerspectivesManager::getSettingsObject( const QString& filePath ) const
+{
+    return std::make_shared<QSettings>(filePath, QSettings::IniFormat);
+}
+
+void PerspectivesManager::loadPerspectives()
+{
+    if ( !m_perspectivesFolder.isEmpty() )
+    {
+        QDir().mkpath( m_perspectivesFolder );
+
+        m_perspectives.clear();
+        
+        auto mainSettings = getSettingsObject( getSettingsFileName( "", false ) );
+        std::string debug = mainSettings->fileName().toStdString();
+
+        int Size = mainSettings->beginReadArray("Perspectives");
+        
+        for (int i = 0; i < Size; ++i)
+        {
+            mainSettings->setArrayIndex(i);
+            QString perspective = mainSettings->value("Name").toString();
+            
+            if ( !perspective.isEmpty() )
+            {
+                // load perspective file:
+                auto toLoad = getSettingsFileName( perspective, false );
+                auto loaded = getSettingsFileName( perspective, true );
+
+#ifdef _DEBUG
+                std::string debug1 = loaded.toStdString();
+                std::string debug2 = toLoad.toStdString();
+#endif
+
+                QFile::remove( loaded );
+                if ( !QFile::copy( toLoad, loaded ) )
+                    assert( false );
+
+                m_perspectives[perspective].settings = getSettingsObject( loaded );
+
+                // load group info:
+                mainSettings->beginGroup(GROUP_PREFIX);
+                for ( auto key : mainSettings->allKeys() )
+                    m_perspectives[perspective].groups[key] = mainSettings->value( key ).toStringList();
+                mainSettings->endGroup();
+            }
+            else
+            {
+                assert( false );
+            }
+        }
+
+        mainSettings->endArray();
+    }
+
+    emit perspectivesListChanged();
+}
+
+void PerspectivesManager::savePerspectives() const
+{
+    if ( !m_perspectivesFolder.isEmpty() )
+    {
+        auto mainSettings = getSettingsObject( getSettingsFileName( "", false ) );
+
+        // Save list of perspective and group organization
+        mainSettings->beginWriteArray("Perspectives", m_perspectives.size());
+        int i = 0;
+        for ( auto perspective : m_perspectives.keys() )
+        {
+            mainSettings->setArrayIndex(i);
+            mainSettings->setValue("Name", perspective);
+            mainSettings->beginGroup(GROUP_PREFIX);
+            for ( auto group : m_perspectives[perspective].groups.keys() )
+            {
+                mainSettings->setValue( group, m_perspectives[perspective].groups[group] );
+            }
+            mainSettings->endGroup();
+            ++i;
+        }
+        mainSettings->endArray();
+
+        // Save perspectives themselves
+        for ( auto perspectiveName : m_perspectives.keys() )
+        {
+            auto toSave = getSettingsFileName( perspectiveName, false );
+            QSettings& settings = *(m_perspectives[perspectiveName].settings);
+            settings.sync();
+
+#ifdef _DEBUG
+            std::string debug1 = settings.fileName().toStdString();
+            std::string debug2 = toSave.toStdString();
+#endif
+
+            QFile::remove( toSave );
+            if ( !QFile::copy( settings.fileName(), toSave ) )
+                assert( false );
+        }
+    }
+}

examples/dockindock/perspectives.h

@@ -0,0 +1,59 @@
+#pragma once
+
+#include <QObject>
+#include <QMap>
+#include <QString>
+
+#include <memory>
+
+class QMenu;
+class QSettings;
+
+namespace QtAdsUtl
+{
+
+class DockInDockWidget;
+class PerspectivesManager : public QObject
+{
+    Q_OBJECT
+
+public:
+    PerspectivesManager( const QString& perspectivesFolder );
+    virtual ~PerspectivesManager();
+
+    QStringList perspectiveNames() const;
+
+    void addPerspective( const QString& name, DockInDockWidget& widget );
+    void openPerspective( const QString& name, DockInDockWidget& widget );
+    void removePerspectives();
+    void removePerspective( const QString& name );
+
+    void loadPerspectives();
+    void savePerspectives() const;
+
+signals:
+    void perspectivesListChanged();
+    void openingPerspective();
+    void openedPerspective();
+
+private:
+
+    // Partially bypass ADS perspective management, store list here
+    // and then ADS will only have one perspective loaded
+    // this is because all docking widgets must exist when a perspective is loaded
+    // we will guarantee that!
+    class PerspectiveInfo
+    {
+    public:
+        std::shared_ptr<QSettings> settings;
+        QMap<QString,QStringList> groups;
+    };
+    QMap<QString,PerspectiveInfo> m_perspectives;
+
+    QString m_perspectivesFolder;
+    QString getSettingsFileName( const QString& perspective, bool temp ) const;
+    std::shared_ptr<QSettings> getSettingsObject( const QString& filePath ) const;
+};
+
+}
+

examples/dockindock/perspectives.py

@@ -0,0 +1,203 @@
+import os
+import tempfile
+import shutil
+import atexit
+
+from PyQt5.QtCore import pyqtSignal, QSettings, QObject
+from PyQtAds import QtAds
+
+from dockindockmanager import DockInDockManager
+from dockindock import DockInDockWidget
+
+GROUP_PREFIX = "Group"
+
+def findWidget(name, managers: 'list[DockInDockManager]') -> QtAds.CDockWidget:
+        for mgr in managers:
+            widget = mgr.findDockWidget(name)
+            if widget:
+                return widget
+
+
+class PerspectiveInfo:
+    # Partially bypass ADS perspective management, store list here
+    # and then ADS will only have one perspective loaded
+    # this is because all docking widgets must exist when a perspective is loaded
+    # we will guarantee that!
+    
+    settings = QSettings()
+    groups: 'dict[str, list[str]]' = {}
+
+
+class PerspectivesManager(QObject):
+    perspectivesListChanged = pyqtSignal()
+    openingPerspective = pyqtSignal()
+    openedPerspective = pyqtSignal()
+
+    def __init__(self, perspectives_folder):
+        super().__init__()
+        self.__perspectives_folder = perspectives_folder
+        self.__perspectives = {}
+        atexit.register(self.cleanup)
+        
+    def cleanup(self):
+        for perspective in self.__perspectives.values():
+            filename = perspective.settings.fileName()
+            try:
+                os.remove(filename)
+            except FileNotFoundError:
+                pass
+            
+    def perspectiveNames(self) -> 'list[str]':
+        return self.__perspectives.keys()
+        
+    def addPerspective(self, name: str, widget: DockInDockWidget) -> None:
+        if self.__perspectives_folder:
+            self.__perspectives[name] = perspective = PerspectiveInfo()
+            perspective.settings = self.getSettingsObject(self.getSettingsFileName(name, True))
+            perspective.groups = widget.getManager().getGroupContents()
+            
+            # save perspective internally
+            widget.getManager().addPerspectiveRec(name)
+            # store it in QSettings object
+            widget.getManager().savePerspectivesRec(perspective.settings)
+            # remove internal perspectives
+            widget.getManager().removePerspectives(widget.getManager().perspectiveNames())
+            
+        self.perspectivesListChanged.emit()
+                
+    def openPerspective(name: str, widget: DockInDockWidget) -> None:
+        assert widget.getTopLevelDockWidget() == widget
+        
+        if self.__perspectives_folder:
+            if name in self.__perspectives:
+                self.openingPerspective.emit()
+                
+                if widget.canCreateNewGroups():
+                    cur_groups = widget.getManager().allManagers(True, True)
+                    for group in self.__perspectives[name].groups.keys():
+                        found = False
+                        for curgroup in cur_groups:
+                            if curgroup.getPerspectiveGroupName() == group:
+                                found = True
+                                break
+                        if not found:
+                            group = DockInDockManager.getGroupNameFromPersistGroupName(group)
+                            
+                        # restore group in file but not in GUI yet
+                        widget.createGroup(group, None)
+                        
+                    cur_groups = widget.getManager().allManagers(False, True)
+                    for curgroup in cur_groups:
+                        if curgroup.getPersistGroupName() not in self.__perspectives[name].groups.keys():
+                            widget.destroyGroup(curgroup.parent())
+                            
+                managers = widget.getManager().allManagers(True, True)
+                for group in self.__perspectives[name].groups().keys():
+                    for mgr in managers:
+                        if mgr.getPersistGroupName() == group:
+                            for widget_name in self.__perspectives[name].groups[group]:
+                                widget = findWidget(widget_name, [mgr])
+                                if widget:
+                                    pass # OK, widget is already in the good manager!
+                                else:
+                                    widget = findWidget(widget_name, managers)
+                                    if widget:
+                                        # move dock widget in the same group as it used to be when perspective was saved
+                                        # this guarantee load/open perspectives will work smartly
+                                        MoveDockWidgetAction.move(widget, mgr)
+                                        
+                 # internally load perspectives from QSettings
+                widget.getManager().loadPerspectivesRec(self.__perspectives[name].settings)
+                # load perspective (update GUI)
+                widget.getManager().openPerspectiveRec(name)
+                # remove internal perspectives
+                widget.getManager().removePerspectives(widget.getManager().perspectiveNames())
+
+                self.openedPerspective().emit()
+        else:
+            assert False
+            
+    def removePerspectives(self) -> None:
+        self.__perspectives.clear()
+        self.perspectivesListChanged.emit()
+        
+    def removePerspective(self, name: str) -> None:
+        del self.__perspectives[name]
+        self.perspectivesListChanged.emit()
+        
+    def getSettingsFileName(self, perspective: str, temp: bool) -> str:
+        name = "perspectives.ini" if not perspective else f"perspectives_{perspective + '.tmp' if temp else perspective + '.ini'}"
+        
+        return os.path.join(self.__perspectives_folder, name)
+        
+    def getSettingsObject(self, file_path: str) -> QSettings:
+        return QSettings(file_path, QSettings.IniFormat)
+        
+    def loadPerspectives(self) -> None:
+        if self.__perspectives_folder:
+            tempfile.mktemp(dir=self.__perspectives_folder)
+            
+            self.__perspectives.clear()
+            
+            main_settings = self.getSettingsObject(self.getSettingsFileName("", False))
+            debug = main_settings.fileName()
+            
+            size = main_settings.beginReadArray("Perspectives")
+            
+            for i in range(0, size):
+                main_settings.setArrayIndex(i)
+                perspective = main_settings.value("Name")
+                
+                if perspective:
+                    to_load = self.getSettingsFileName(perspective, False)
+                    loaded = self.getSettingsFileName(perspective, True)
+                    
+                    try:
+                        os.remove(loaded)
+                    except FileNotFoundError:
+                        pass
+                    if not shutil.copy(to_load, loaded):
+                        assert False
+                        
+                    self.__perspectives[perspective] = PerspectiveInfo()
+                    self.__perspectives[perspective].settings = self.getSettingsObject(loaded)
+                    
+                    # load group info:
+                    main_settings.beginGroup(GROUP_PREFIX)
+                    for key in main_settings.allKeys():
+                        self.__perspectives[perspective].groups[key] = main_settings.value(key)
+                    main_settings.endGroup()
+                else:
+                    assert False
+                    
+            main_settings.endArray()
+            
+        self.perspectivesListChanged.emit()
+        
+    def savePerspectives(self) -> None:
+        if self.__perspectives_folder:
+            main_settings = self.getSettingsObject(self.getSettingsFileName("", False))
+            
+            # Save list of perspective and group organization
+            main_settings.beginWriteArray("Perspectives", len(self.__perspectives))
+            for i, perspective in enumerate(self.__perspectives.keys()):
+                main_settings.setArrayIndex(i)
+                main_settings.setValue("Name", perspective)
+                main_settings.beginGroup(GROUP_PREFIX)
+                for group in self.__perspectives[perspective].groups.keys():
+                    main_settings.setValue(group, list(self.__perspectives[perspective].groups[group]))
+                main_settings.endGroup()
+            main_settings.endArray()
+            
+            # Save perspectives themselves
+            for perspective_name in self.__perspectives.keys():
+                to_save = self.getSettingsFileName(perspective_name, False)
+                settings = self.__perspectives[perspective_name].settings
+                settings.sync()
+
+                try:
+                    os.remove(to_save)
+                except FileNotFoundError:
+                    pass
+                if not shutil.copy(settings.fileName(), to_save):
+                    assert False

examples/emptydockarea/CMakeLists.txt

@@ -0,0 +1,28 @@
+cmake_minimum_required(VERSION 3.5)
+project(ads_example_centralwidget VERSION ${VERSION_SHORT}) 
+find_package(QT NAMES Qt6 Qt5 COMPONENTS Core REQUIRED)
+find_package(Qt${QT_VERSION_MAJOR} 5.5 COMPONENTS Core Gui Widgets REQUIRED)
+set(CMAKE_INCLUDE_CURRENT_DIR ON)
+add_executable(EmptyDockAreaExample WIN32 
+    main.cpp
+    mainwindow.cpp
+    mainwindow.ui
+)
+target_include_directories(EmptyDockAreaExample PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/../../src")
+target_link_libraries(EmptyDockAreaExample PRIVATE qtadvanceddocking)
+target_link_libraries(EmptyDockAreaExample PUBLIC Qt${QT_VERSION_MAJOR}::Core 
+                                                  Qt${QT_VERSION_MAJOR}::Gui 
+                                                  Qt${QT_VERSION_MAJOR}::Widgets)
+set_target_properties(EmptyDockAreaExample PROPERTIES 
+    AUTOMOC ON
+    AUTORCC ON
+    AUTOUIC ON
+    CXX_STANDARD 14
+    CXX_STANDARD_REQUIRED ON
+    CXX_EXTENSIONS OFF
+    VERSION ${VERSION_SHORT}
+    EXPORT_NAME "Qt Advanced Docking System Empty Dock Area Example"
+    ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/${ads_PlatformDir}/lib"
+    LIBRARY_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/${ads_PlatformDir}/lib"
+    RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/${ads_PlatformDir}/bin"
+)

examples/emptydockarea/emptydockarea.pro

@@ -0,0 +1,34 @@
+ADS_OUT_ROOT = $${OUT_PWD}/../..
+
+QT       += core gui widgets
+
+TARGET = EmptyDockareaExample
+DESTDIR = $${ADS_OUT_ROOT}/lib
+TEMPLATE = app
+CONFIG += c++14
+CONFIG += debug_and_release
+adsBuildStatic {
+    DEFINES += ADS_STATIC
+}
+
+# The following define makes your compiler emit warnings if you use
+# any Qt feature that has been marked deprecated (the exact warnings
+# depend on your compiler). Please consult the documentation of the
+# deprecated API in order to know how to port your code away from it.
+DEFINES += QT_DEPRECATED_WARNINGS
+
+SOURCES += \
+    main.cpp \
+    mainwindow.cpp
+
+HEADERS += \
+    mainwindow.h
+
+FORMS += \
+    mainwindow.ui
+
+LIBS += -L$${ADS_OUT_ROOT}/lib
+include(../../ads.pri)
+INCLUDEPATH += ../../src
+DEPENDPATH += ../../src
+

examples/emptydockarea/main.cpp

@@ -0,0 +1,10 @@
+#include <mainwindow.h>
+#include <QApplication>
+
+int main(int argc, char *argv[])
+{
+    QApplication a(argc, argv);
+    CMainWindow w;
+    w.show();
+    return a.exec();
+}

examples/emptydockarea/main.py

@@ -0,0 +1,108 @@
+import sys
+import os
+
+from PyQt5 import uic
+from PyQt5.QtCore import Qt, QSignalBlocker
+from PyQt5.QtWidgets import (QApplication, QMainWindow, QLabel, QComboBox, QTableWidget,
+                             QAction, QWidgetAction, QSizePolicy, QInputDialog)
+from PyQt5.QtGui import QCloseEvent
+from PyQtAds import QtAds
+
+    
+UI_FILE = os.path.join(os.path.dirname(__file__), 'mainwindow.ui')
+MainWindowUI, MainWindowBase = uic.loadUiType(UI_FILE)
+
+
+class CMainWindow(MainWindowUI, MainWindowBase):
+    def __init__(self, parent=None):
+        super().__init__(parent)
+        
+        self.setupUi(self)
+
+        QtAds.CDockManager.setConfigFlag(QtAds.CDockManager.OpaqueSplitterResize, True)
+        QtAds.CDockManager.setConfigFlag(QtAds.CDockManager.XmlCompressionEnabled, False)
+        QtAds.CDockManager.setConfigFlag(QtAds.CDockManager.FocusHighlighting, True)
+        self.dock_manager = QtAds.CDockManager(self)
+        
+        # Set central widget
+        label = QLabel()
+        label.setText("This is a DockArea which is always visible, even if it does not contain any DockWidgets.")
+        label.setAlignment(Qt.AlignCenter)
+        central_dock_widget = QtAds.CDockWidget("CentralWidget")
+        central_dock_widget.setWidget(label)
+        central_dock_widget.setFeature(QtAds.CDockWidget.NoTab, True)
+        central_dock_area = self.dock_manager.setCentralWidget(central_dock_widget)
+
+        # create other dock widgets
+        table = QTableWidget()
+        table.setColumnCount(3)
+        table.setRowCount(10)
+        table_dock_widget = QtAds.CDockWidget("Table 1")
+        table_dock_widget.setWidget(table)
+        table_dock_widget.setMinimumSizeHintMode(QtAds.CDockWidget.MinimumSizeHintFromDockWidget)
+        table_dock_widget.resize(250, 150)
+        table_dock_widget.setMinimumSize(200,150)
+        self.dock_manager.addDockWidgetTabToArea(table_dock_widget, central_dock_area)
+        table_area = self.dock_manager.addDockWidget(QtAds.DockWidgetArea.LeftDockWidgetArea, table_dock_widget)
+        self.menuView.addAction(table_dock_widget.toggleViewAction())
+
+        table = QTableWidget()
+        table.setColumnCount(5)
+        table.setRowCount(1020)
+        table_dock_widget = QtAds.CDockWidget("Table 2")
+        table_dock_widget.setWidget(table)
+        table_dock_widget.setMinimumSizeHintMode(QtAds.CDockWidget.MinimumSizeHintFromDockWidget)
+        table_dock_widget.resize(250, 150)
+        table_dock_widget.setMinimumSize(200,150)
+        self.dock_manager.addDockWidget(QtAds.DockWidgetArea.BottomDockWidgetArea, table_dock_widget, table_area)
+        self.menuView.addAction(table_dock_widget.toggleViewAction())
+
+        properties_table = QTableWidget()
+        properties_table.setColumnCount(3)
+        properties_table.setRowCount(10)
+        properties_dock_widget = QtAds.CDockWidget("Properties")
+        properties_dock_widget.setWidget(properties_table)
+        properties_dock_widget.setMinimumSizeHintMode(QtAds.CDockWidget.MinimumSizeHintFromDockWidget)
+        properties_dock_widget.resize(250, 150)
+        properties_dock_widget.setMinimumSize(200,150)
+        self.dock_manager.addDockWidget(QtAds.DockWidgetArea.RightDockWidgetArea, properties_dock_widget, central_dock_area)
+        self.menuView.addAction(properties_dock_widget.toggleViewAction())
+
+        self.createPerspectiveUi()
+        
+    def createPerspectiveUi(self):
+        save_perspective_action = QAction("Create Perspective", self)
+        save_perspective_action.triggered.connect(self.savePerspective)
+        perspective_list_action = QWidgetAction(self)
+        self.perspective_combo_box = QComboBox(self)
+        self.perspective_combo_box.setSizeAdjustPolicy(QComboBox.AdjustToContents)
+        self.perspective_combo_box.setSizePolicy(QSizePolicy.Preferred, QSizePolicy.Preferred)
+        self.perspective_combo_box.activated[str].connect(self.dock_manager.openPerspective)
+        perspective_list_action.setDefaultWidget(self.perspective_combo_box)
+        self.toolBar.addSeparator()
+        self.toolBar.addAction(perspective_list_action)
+        self.toolBar.addAction(save_perspective_action)
+        
+    def savePerspective(self):
+        perspective_name, ok = QInputDialog.getText(self, "Save Perspective", "Enter unique name:")
+        if not perspective_name or not ok:
+            return
+        
+        self.dock_manager.addPerspective(perspective_name)
+        blocker = QSignalBlocker(self.perspective_combo_box)
+        self.perspective_combo_box.clear()
+        self.perspective_combo_box.addItems(self.dock_manager.perspectiveNames())
+        self.perspective_combo_box.setCurrentText(perspective_name)
+        
+    def closeEvent(self, event: QCloseEvent):
+        # Delete dock manager here to delete all floating widgets. This ensures
+        # that all top level windows of the dock manager are properly closed
+        self.dock_manager.deleteLater()
+        super().closeEvent(event)
+        
+if __name__ == '__main__':
+    app = QApplication(sys.argv)
+    
+    w = CMainWindow()
+    w.show()
+    app.exec_()

examples/emptydockarea/mainwindow.cpp

@@ -0,0 +1,135 @@
+#include "mainwindow.h"
+
+#include "ui_mainwindow.h"
+
+#include <QWidgetAction>
+#include <QLabel>
+#include <QCalendarWidget>
+#include <QTreeView>
+#include <QFileSystemModel>
+#include <QTableWidget>
+#include <QHBoxLayout>
+#include <QRadioButton>
+#include <QPushButton>
+#include <QInputDialog>
+#include <QFileDialog>
+#include <QSettings>
+#include <QMessageBox>
+#include <QPlainTextEdit>
+#include <QToolBar>
+
+#include "DockAreaWidget.h"
+#include "DockAreaTitleBar.h"
+#include "DockAreaTabBar.h"
+#include "FloatingDockContainer.h"
+#include "DockComponentsFactory.h"
+
+using namespace ads;
+
+
+CMainWindow::CMainWindow(QWidget *parent)
+    : QMainWindow(parent)
+    , ui(new Ui::CMainWindow)
+{
+    ui->setupUi(this);
+    CDockManager::setConfigFlag(CDockManager::OpaqueSplitterResize, true);
+    CDockManager::setConfigFlag(CDockManager::XmlCompressionEnabled, false);
+    CDockManager::setConfigFlag(CDockManager::FocusHighlighting, true);
+    DockManager = new CDockManager(this);
+
+    // Set central widget
+    QLabel* label = new QLabel();
+    label->setText("This is a DockArea which is always visible, even if it does not contain any DockWidgets.");
+    label->setAlignment(Qt::AlignCenter);
+    CDockWidget* CentralDockWidget = new CDockWidget("CentralWidget");
+    CentralDockWidget->setWidget(label);
+    CentralDockWidget->setFeature(ads::CDockWidget::NoTab, true);
+    auto* CentralDockArea = DockManager->setCentralWidget(CentralDockWidget);
+
+    // create other dock widgets
+    QTableWidget* table = new QTableWidget();
+    table->setColumnCount(3);
+    table->setRowCount(10);
+    CDockWidget* TableDockWidget = new CDockWidget("Table 1");
+    TableDockWidget->setWidget(table);
+    TableDockWidget->setMinimumSizeHintMode(CDockWidget::MinimumSizeHintFromDockWidget);
+    TableDockWidget->resize(250, 150);
+    TableDockWidget->setMinimumSize(200,150);
+    DockManager->addDockWidgetTabToArea(TableDockWidget, CentralDockArea);
+    auto TableArea = DockManager->addDockWidget(DockWidgetArea::LeftDockWidgetArea, TableDockWidget);
+    ui->menuView->addAction(TableDockWidget->toggleViewAction());
+
+    table = new QTableWidget();
+    table->setColumnCount(5);
+    table->setRowCount(1020);
+    TableDockWidget = new CDockWidget("Table 2");
+    TableDockWidget->setWidget(table);
+    TableDockWidget->setMinimumSizeHintMode(CDockWidget::MinimumSizeHintFromDockWidget);
+    TableDockWidget->resize(250, 150);
+    TableDockWidget->setMinimumSize(200,150);
+    DockManager->addDockWidget(DockWidgetArea::BottomDockWidgetArea, TableDockWidget, TableArea);
+    ui->menuView->addAction(TableDockWidget->toggleViewAction());
+
+    QTableWidget* propertiesTable = new QTableWidget();
+    propertiesTable->setColumnCount(3);
+    propertiesTable->setRowCount(10);
+    CDockWidget* PropertiesDockWidget = new CDockWidget("Properties");
+    PropertiesDockWidget->setWidget(propertiesTable);
+    PropertiesDockWidget->setMinimumSizeHintMode(CDockWidget::MinimumSizeHintFromDockWidget);
+    PropertiesDockWidget->resize(250, 150);
+    PropertiesDockWidget->setMinimumSize(200,150);
+    DockManager->addDockWidget(DockWidgetArea::RightDockWidgetArea, PropertiesDockWidget, CentralDockArea);
+    ui->menuView->addAction(PropertiesDockWidget->toggleViewAction());
+
+    createPerspectiveUi();
+}
+
+CMainWindow::~CMainWindow()
+{
+    delete ui;
+}
+
+
+void CMainWindow::createPerspectiveUi()
+{
+	SavePerspectiveAction = new QAction("Create Perspective", this);
+	connect(SavePerspectiveAction, SIGNAL(triggered()), SLOT(savePerspective()));
+	PerspectiveListAction = new QWidgetAction(this);
+	PerspectiveComboBox = new QComboBox(this);
+	PerspectiveComboBox->setSizeAdjustPolicy(QComboBox::AdjustToContents);
+	PerspectiveComboBox->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Preferred);
+	connect(PerspectiveComboBox, SIGNAL(activated(const QString&)),
+		DockManager, SLOT(openPerspective(const QString&)));
+	PerspectiveListAction->setDefaultWidget(PerspectiveComboBox);
+	ui->toolBar->addSeparator();
+	ui->toolBar->addAction(PerspectiveListAction);
+	ui->toolBar->addAction(SavePerspectiveAction);
+}
+
+
+void CMainWindow::savePerspective()
+{
+	QString PerspectiveName = QInputDialog::getText(this, "Save Perspective", "Enter unique name:");
+	if (PerspectiveName.isEmpty())
+	{
+		return;
+	}
+
+	DockManager->addPerspective(PerspectiveName);
+	QSignalBlocker Blocker(PerspectiveComboBox);
+	PerspectiveComboBox->clear();
+	PerspectiveComboBox->addItems(DockManager->perspectiveNames());
+	PerspectiveComboBox->setCurrentText(PerspectiveName);
+}
+
+
+//============================================================================
+void CMainWindow::closeEvent(QCloseEvent* event)
+{
+    // Delete dock manager here to delete all floating widgets. This ensures
+    // that all top level windows of the dock manager are properly closed
+    DockManager->deleteLater();
+	QMainWindow::closeEvent(event);
+}
+
+

examples/emptydockarea/mainwindow.h

@@ -0,0 +1,43 @@
+#ifndef MAINWINDOW_H
+#define MAINWINDOW_H
+
+#include <QMainWindow>
+#include <QComboBox>
+#include <QWidgetAction>
+
+#include "DockManager.h"
+#include "DockAreaWidget.h"
+#include "DockWidget.h"
+
+QT_BEGIN_NAMESPACE
+namespace Ui { class CMainWindow; }
+QT_END_NAMESPACE
+
+class CMainWindow : public QMainWindow
+{
+    Q_OBJECT
+
+public:
+    CMainWindow(QWidget *parent = nullptr);
+    ~CMainWindow();
+
+protected:
+	virtual void closeEvent(QCloseEvent* event) override;
+
+private:
+	QAction* SavePerspectiveAction = nullptr;
+	QWidgetAction* PerspectiveListAction = nullptr;
+	QComboBox* PerspectiveComboBox = nullptr;
+
+    Ui::CMainWindow *ui;
+
+    ads::CDockManager* DockManager;
+    ads::CDockAreaWidget* StatusDockArea;
+    ads::CDockWidget* TimelineDockWidget;
+
+    void createPerspectiveUi();
+
+private slots:
+	void savePerspective();
+};
+#endif // MAINWINDOW_H

examples/emptydockarea/mainwindow.ui

@@ -0,0 +1,47 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>CMainWindow</class>
+ <widget class="QMainWindow" name="CMainWindow">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>1284</width>
+    <height>757</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>MainWindow</string>
+  </property>
+  <widget class="QWidget" name="centralwidget"/>
+  <widget class="QMenuBar" name="menubar">
+   <property name="geometry">
+    <rect>
+     <x>0</x>
+     <y>0</y>
+     <width>1284</width>
+     <height>21</height>
+    </rect>
+   </property>
+   <widget class="QMenu" name="menuView">
+    <property name="title">
+     <string>View</string>
+    </property>
+   </widget>
+   <addaction name="menuView"/>
+  </widget>
+  <widget class="QToolBar" name="toolBar">
+   <property name="windowTitle">
+    <string>toolBar</string>
+   </property>
+   <attribute name="toolBarArea">
+    <enum>TopToolBarArea</enum>
+   </attribute>
+   <attribute name="toolBarBreak">
+    <bool>false</bool>
+   </attribute>
+  </widget>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>

examples/examples.pro

@@ -4,4 +4,6 @@ SUBDIRS = \
     centralwidget \
 	simple \
 	sidebar \
-	deleteonclose
+	deleteonclose \
+	emptydockarea \
+	dockindock

examples/sidebar/CMakeLists.txt

@@ -1,6 +1,7 @@
 cmake_minimum_required(VERSION 3.5)
 project(ads_example_sidebar VERSION ${VERSION_SHORT}) 
-find_package(Qt5 5.5 COMPONENTS Core Gui Widgets REQUIRED)
+find_package(QT NAMES Qt6 Qt5 COMPONENTS Core REQUIRED)
+find_package(Qt${QT_VERSION_MAJOR} 5.5 COMPONENTS Core Gui Widgets REQUIRED)
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
 add_executable(SidebarExample WIN32 
     main.cpp
@@ -9,7 +10,9 @@ add_executable(SidebarExample WIN32
 )
 target_include_directories(SidebarExample PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/../../src")
 target_link_libraries(SidebarExample PRIVATE qtadvanceddocking)
-target_link_libraries(SidebarExample PUBLIC Qt5::Core Qt5::Gui Qt5::Widgets)
+target_link_libraries(SidebarExample PUBLIC Qt${QT_VERSION_MAJOR}::Core 
+                                            Qt${QT_VERSION_MAJOR}::Gui 
+                                            Qt${QT_VERSION_MAJOR}::Widgets)
 set_target_properties(SidebarExample PROPERTIES 
     AUTOMOC ON
     AUTORCC ON

examples/sidebar/sidebar.pro

@@ -25,23 +25,7 @@ FORMS += \
         
 
 LIBS += -L$${ADS_OUT_ROOT}/lib
-
-# Dependency: AdvancedDockingSystem (shared)
-CONFIG(debug, debug|release){
-    win32 {
-        LIBS += -lqtadvanceddockingd
-    }
-    else:mac {
-        LIBS += -lqtadvanceddocking_debug
-    }
-    else {
-        LIBS += -lqtadvanceddocking
-    }
-}
-else{
-    LIBS += -lqtadvanceddocking
-}
-
+include(../../ads.pri)
 INCLUDEPATH += ../../src
 DEPENDPATH += ../../src    
 

examples/simple/CMakeLists.txt

@@ -1,6 +1,7 @@
 cmake_minimum_required(VERSION 3.5)
 project(ads_example_simple VERSION ${VERSION_SHORT}) 
-find_package(Qt5 5.5 COMPONENTS Core Gui Widgets REQUIRED)
+find_package(QT NAMES Qt6 Qt5 COMPONENTS Core REQUIRED)
+find_package(Qt${QT_VERSION_MAJOR} 5.5 COMPONENTS Core Gui Widgets REQUIRED)
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
 add_executable(SimpleExample WIN32 
     main.cpp
@@ -9,7 +10,9 @@ add_executable(SimpleExample WIN32
 )
 target_include_directories(SimpleExample PRIVATE "${CMAKE_CURRENT_SOURCE_DIR}/../../src")
 target_link_libraries(SimpleExample PRIVATE qtadvanceddocking)
-target_link_libraries(SimpleExample PUBLIC Qt5::Core Qt5::Gui Qt5::Widgets)
+target_link_libraries(SimpleExample PUBLIC Qt${QT_VERSION_MAJOR}::Core 
+                                           Qt${QT_VERSION_MAJOR}::Gui 
+                                           Qt${QT_VERSION_MAJOR}::Widgets)
 set_target_properties(SimpleExample PROPERTIES 
     AUTOMOC ON
     AUTORCC ON

examples/simple/main.py

@@ -21,7 +21,7 @@ class MainWindow(MainWindowUI, MainWindowBase):
  
         # Create the dock manager. Because the parent parameter is a QMainWindow
         # the dock manager registers itself as the central widget.
-        self.dock_manager1 = QtAds.CDockManager(self)
+        self.dock_manager = QtAds.CDockManager(self)
         
         # Create example content label - this can be any application specific
         # widget
@@ -35,41 +35,13 @@ class MainWindow(MainWindowUI, MainWindowBase):
         dock_widget = QtAds.CDockWidget("Label 1")
         dock_widget.setWidget(l)
         
-        l = QLabel()
-        l.setWordWrap(True)
-        l.setAlignment(Qt.AlignTop | Qt.AlignLeft);
-        l.setText("Lorem ipsum dolor sit amet, consectetuer adipiscing elit. ")
-
-        # Create a dock widget with the title Label 1 and set the created label
-        # as the dock widget content
-        dock_widget2 = QtAds.CDockWidget("Label 2")
-        dock_widget2.setWidget(l)
 
         # Add the toggleViewAction of the dock widget to the menu to give
         # the user the possibility to show the dock widget if it has been closed
         self.menuView.addAction(dock_widget.toggleViewAction())
 
         # Add the dock widget to the top dock widget area
-        self.dock_manager1.addDockWidget(QtAds.TopDockWidgetArea, dock_widget)
-        
-        def remove_first_manager():
-            self.dock_manager1.removeDockWidget(dock_widget)
-            del self.dock_manager1
-        QTimer.singleShot(3000, remove_first_manager)
-            
-        def add_second_manager():
-            self.dock_manager2 = QtAds.CDockManager(self)
-            self.dock_manager2.addDockWidget(QtAds.TopDockWidgetArea, dock_widget)
-        QTimer.singleShot(5000, add_second_manager)
-        
-    def closeEvent(self, event: QCloseEvent):
-        super().closeEvent(event)
-        
-        if hasattr(self, 'dock_manager1'):
-            self.dock_manager1.deleteLater()
-            
-        if hasattr(self, 'dock_manager2'):
-            self.dock_manager2.deleteLater()
+        self.dock_manager.addDockWidget(QtAds.TopDockWidgetArea, dock_widget)
 
 
 if __name__ == '__main__':

examples/simple/simple.pro

@@ -25,23 +25,7 @@ FORMS += \
         
 
 LIBS += -L$${ADS_OUT_ROOT}/lib
-
-# Dependency: AdvancedDockingSystem (shared)
-CONFIG(debug, debug|release){
-    win32 {
-        LIBS += -lqtadvanceddockingd
-    }
-    else:mac {
-        LIBS += -lqtadvanceddocking_debug
-    }
-    else {
-        LIBS += -lqtadvanceddocking
-    }
-}
-else{
-    LIBS += -lqtadvanceddocking
-}
-
+include(../../ads.pri)
 INCLUDEPATH += ../../src
 DEPENDPATH += ../../src    
 

sip/DockAreaWidget.sip

@@ -28,6 +28,13 @@ protected slots:
 	void toggleView(bool Open);
     
 public:
+    enum eDockAreaFlag
+	{
+		HideSingleWidgetTitleBar,
+		DefaultFlags
+	};
+    typedef QFlags<ads::CDockAreaWidget::eDockAreaFlag> DockAreaFlags;
+    
 	CDockAreaWidget(ads::CDockManager* DockManager /TransferThis/, ads::CDockContainerWidget* parent /TransferThis/);
 	virtual ~CDockAreaWidget();
 	ads::CDockManager* dockManager() const;
@@ -51,8 +58,13 @@ public:
 
 	void setAllowedAreas(DockWidgetAreas areas);
 	DockWidgetAreas allowedAreas() const;
-	void setHideSingleWidgetTitleBar(bool hide);
 	CDockAreaTitleBar* titleBar() const;
+    
+    DockAreaFlags dockAreaFlags() const;
+    void setDockAreaFlags(DockAreaFlags Flags);
+    void setDockAreaFlag(eDockAreaFlag Flag, bool On);
+    
+    bool isCentralWidgetArea() const;
 
 public slots:
 	void setCurrentIndex(int index);

sip/DockContainerWidget.sip

@@ -32,6 +32,7 @@ protected:
 	ads::CDockWidget* topLevelDockWidget() const;
 	ads::CDockAreaWidget* topLevelDockArea() const;
     QList<ads::CDockWidget*> dockWidgets() const;
+    void updateSplitterHandles(QSplitter* splitter);
     
 public:
 	/**

sip/DockFocusController.sip

@@ -20,6 +20,8 @@ public:
 
 	void notifyWidgetOrAreaRelocation(QWidget* RelocatedWidget);
 	void notifyFloatingWidgetDrop(ads::CFloatingDockContainer* FloatingWidget);
+    ads::CDockWidget* focusedDockWidget() const;
+    void setDockWidgetTabFocused(ads::CDockWidgetTab* Tab);
 
 public slots:
 	void setDockWidgetFocused(ads::CDockWidget* focusedNow);

sip/DockManager.sip

@@ -170,6 +170,8 @@ public:
 		HideSingleCentralWidgetTitleBar,
         FocusHighlighting,
         EqualSplitOnInsertion,
+        FloatingContainerForceNativeTitleBar,
+        FloatingContainerForceQWidgetTitleBar,
         DefaultDockAreaButtons,
 		DefaultBaseConfig,
         DefaultOpaqueConfig,
@@ -206,12 +208,17 @@ public:
 	QStringList perspectiveNames() const;
 	void savePerspectives(QSettings& Settings) const;
 	void loadPerspectives(QSettings& Settings);
+    CDockWidget* centralWidget() const;
+    CDockAreaWidget* setCentralWidget(CDockWidget* widget /Transfer/);
 	QAction* addToggleViewActionToMenu(QAction* ToggleViewAction /Transfer/,
 		const QString& Group = QString(), const QIcon& GroupIcon = QIcon());
 	QMenu* viewMenu() const;
 	void setViewMenuInsertionOrder(ads::CDockManager::eViewMenuInsertionOrder Order);
 	bool isRestoringState() const;
 	static int startDragDistance();
+    ads::CDockWidget* focusedDockWidget() const;
+    QList<int> splitterSizes(ads::CDockAreaWidget *ContainedArea) const;
+    void setSplitterSizes(ads::CDockAreaWidget *ContainedArea, const QList<int>& sizes);
 
 public slots:
 	void openPerspective(const QString& PerspectiveName);
@@ -226,6 +233,7 @@ signals:
     void perspectiveOpened(const QString& PerspectiveName);
 	void floatingWidgetCreated(ads::CFloatingDockContainer*);
     void dockAreaCreated(ads::CDockAreaWidget*);
+    void dockWidgetAdded(ads::CDockWidget* DockWidget);
     void dockWidgetAboutToBeRemoved(ads::CDockWidget*);
     void dockWidgetRemoved(ads::CDockWidget*);
     void focusedDockWidgetChanged(ads::CDockWidget*, ads::CDockWidget*);

sip/DockSplitter.sip

@@ -18,6 +18,7 @@ public:
 	bool hasVisibleContent() const;
 	QWidget* firstWidget() const;
 	QWidget* lastWidget() const;
+    bool isResizingWithContainer() const;
 
 };
 

sip/DockWidget.sip

@@ -32,8 +32,11 @@ public:
 		DockWidgetDeleteOnClose,
         CustomCloseHandling,
         DockWidgetFocusable,
+        DockWidgetForceCloseWithArea,
+        NoTab,
         DefaultDockWidgetFeatures,
         AllDockWidgetFeatures,
+        DockWidgetAlwaysCloseAndDelete,
 		NoDockWidgetFeatures
 	};
     typedef QFlags<ads::CDockWidget::DockWidgetFeature> DockWidgetFeatures;
@@ -84,6 +87,7 @@ public:
 	QAction* toggleViewAction() const;
 	void setToggleViewActionMode(ads::CDockWidget::eToggleViewActionMode Mode);
 	void setMinimumSizeHintMode(ads::CDockWidget::eMinimumSizeHintMode Mode);
+    bool isCentralWidget() const;
 	void setIcon(const QIcon& Icon);
 	QIcon icon() const;
 	QToolBar* toolBar() const;

sip/DockWidgetTab.sip

@@ -35,6 +35,8 @@ public:
 	virtual bool event(QEvent *e);
 	void setElideMode(Qt::TextElideMode mode);
     void updateStyle();
+    QSize iconSize() const;
+    void setIconSize(const QSize& Size);
 
 public slots:
 	virtual void setVisible(bool visible);

sip/FloatingDockContainer.sip

@@ -52,11 +52,20 @@ protected:
 
 protected:
 	virtual void changeEvent(QEvent *event);
-	virtual void moveEvent(QMoveEvent *event);
-	virtual bool event(QEvent *e);
 	virtual void closeEvent(QCloseEvent *event);
 	virtual void hideEvent(QHideEvent *event);
 	virtual void showEvent(QShowEvent *event);
+    
+    %If (WS_MACX)
+    virtual bool event(QEvent *e);
+	virtual void moveEvent(QMoveEvent *event);
+    %End
+    
+    %If (WS_X11)
+    virtual void moveEvent(QMoveEvent *event);
+	virtual void resizeEvent(QResizeEvent *event);
+    %End
+    
 	%If (WS_WIN)
 	virtual bool nativeEvent(const QByteArray &eventType, void *message, long *result);
 	%End
@@ -72,6 +81,15 @@ public:
     bool hasTopLevelDockWidget() const;
     ads::CDockWidget* topLevelDockWidget() const;
     QList<ads::CDockWidget*> dockWidgets() const;
+    
+    %If (WS_X11)
+    void onMaximizeRequest();
+	void showNormal(bool fixGeometry);
+	void showMaximized();
+	bool isMaximized() const;
+	void show();
+	bool hasNativeTitleBar();
+    %End
 };
 
 };

sip/ads_globals.sip

@@ -1,60 +1,138 @@
-%Import QtWidgets/QtWidgetsmod.sip
-
-%If (Qt_5_0_0 -)
-
-namespace ads
-{
-    %TypeHeaderCode
-    #include <ads_globals.h>
-    %End
-
-    enum DockWidgetArea
-    {
-        NoDockWidgetArea,
-        LeftDockWidgetArea,
-        RightDockWidgetArea,
-        TopDockWidgetArea,
-        BottomDockWidgetArea,
-        CenterDockWidgetArea,
-
-        InvalidDockWidgetArea,
-        OuterDockAreas,
-        AllDockAreas
-    };
-    typedef QFlags<ads::DockWidgetArea> DockWidgetAreas;
-
-
-    enum TitleBarButton
-    {
-        TitleBarButtonTabsMenu,
-        TitleBarButtonUndock,
-        TitleBarButtonClose
-    };
-
-    enum eDragState
-    {
-        DraggingInactive,
-        DraggingMousePressed,
-        DraggingTab,
-        DraggingFloatingWidget
-    };
-
-    enum eIcon
-    {
-        TabCloseIcon,
-        DockAreaMenuIcon,
-        DockAreaUndockIcon,
-        DockAreaCloseIcon,
-
-        IconCount,
-    };
-
-    enum eBitwiseOperator
-    {
-        BitwiseAnd,
-        BitwiseOr
-    };
-
-};
-
-%End
+%Import QtWidgets/QtWidgetsmod.sip
+
+%If (Qt_5_0_0 -)
+
+%ModuleHeaderCode
+PyObject *qtads_FindParent(PyObject* type, const QWidget *child);
+%End
+
+%ModuleCode
+PyObject *qtads_FindParent(PyObject* type, const QWidget *w)
+{
+    // Check that the types checking was successful.
+    if (!type)
+        return 0;
+   
+    QWidget* parentWidget = w->parentWidget();
+
+    while (parentWidget)
+    {
+        PyObject *ParentImpl = sipConvertFromType(parentWidget, sipType_QObject, 0);
+        if (!ParentImpl)
+        {
+            return 0;
+        }
+            
+        if (PyObject_IsInstance(ParentImpl, type))
+            return ParentImpl;
+        
+        Py_DECREF(ParentImpl);
+        
+        parentWidget = parentWidget->parentWidget();
+    }
+    
+    Py_INCREF(Py_None);
+    return Py_None;
+}
+%End
+
+namespace ads
+{
+    %TypeHeaderCode
+    #include <ads_globals.h>
+    %End
+
+    enum DockWidgetArea
+    {
+        NoDockWidgetArea,
+        LeftDockWidgetArea,
+        RightDockWidgetArea,
+        TopDockWidgetArea,
+        BottomDockWidgetArea,
+        CenterDockWidgetArea,
+
+        InvalidDockWidgetArea,
+        OuterDockAreas,
+        AllDockAreas
+    };
+    typedef QFlags<ads::DockWidgetArea> DockWidgetAreas;
+
+
+    enum TitleBarButton
+    {
+        TitleBarButtonTabsMenu,
+        TitleBarButtonUndock,
+        TitleBarButtonClose
+    };
+
+    enum eDragState
+    {
+        DraggingInactive,
+        DraggingMousePressed,
+        DraggingTab,
+        DraggingFloatingWidget
+    };
+
+    enum eIcon
+    {
+        TabCloseIcon,
+        DockAreaMenuIcon,
+        DockAreaUndockIcon,
+        DockAreaCloseIcon,
+
+        IconCount,
+    };
+
+    enum eBitwiseOperator
+    {
+        BitwiseAnd,
+        BitwiseOr
+    };
+    
+    namespace internal
+    {    
+        void replaceSplitterWidget(QSplitter* Splitter, QWidget* From, QWidget* To);
+        void hideEmptyParentSplitters(ads::CDockSplitter* FirstParentSplitter);
+        
+        class CDockInsertParam
+        {
+            %TypeHeaderCode
+            #include <ads_globals.h>
+            %End
+            
+        public:
+            Qt::Orientation orientation() const;
+            bool append() const;
+            int insertOffset() const;
+        };
+        ads::internal::CDockInsertParam dockAreaInsertParameters(ads::DockWidgetArea Area);
+        
+        SIP_PYOBJECT findParent(SIP_PYTYPE type, const QWidget *w) const /TypeHint="QObject"/;
+        %MethodCode
+        sipRes = qtads_FindParent(a0, a1);
+
+        if (!sipRes)
+        {
+            sipIsErr = 1;
+        }
+        %End
+        
+        QPixmap createTransparentPixmap(const QPixmap& Source, qreal Opacity);  
+
+        QPoint globalPositionOf(QMouseEvent* ev);
+
+        void setButtonIcon(QAbstractButton* Button, QStyle::StandardPixmap StandarPixmap, ads::eIcon CustomIconId);
+        
+        enum eRepolishChildOptions
+        {
+            RepolishIgnoreChildren,
+            RepolishDirectChildren,
+            RepolishChildrenRecursively
+        };
+        
+       void repolishStyle(QWidget* w, ads::internal::eRepolishChildOptions Options = ads::internal::RepolishIgnoreChildren); 
+    };
+
+};
+
+%End

sip/linux/FloatingWidgetTitleBar.sip

@@ -15,15 +15,24 @@ protected:
 	virtual void mousePressEvent(QMouseEvent *ev);
 	virtual void mouseReleaseEvent(QMouseEvent *ev);
 	virtual void mouseMoveEvent(QMouseEvent *ev);
+    virtual void mouseDoubleClickEvent(QMouseEvent *event);
+    
+    void setMaximizeIcon(const QIcon& Icon);
+    QIcon maximizeIcon() const;
+    void setNormalIcon(const QIcon& Icon);
+    QIcon normalIcon() const;
 
 public:
 	explicit CFloatingWidgetTitleBar(CFloatingDockContainer *parent /TransferThis/ = 0);
 	virtual ~CFloatingWidgetTitleBar();
 	void enableCloseButton(bool Enable);
 	void setTitle(const QString &Text);
+    void updateStyle();
+    void setMaximizedIcon(bool maximized);
 
 signals:
 	void closeRequested();
+    void maximizeRequested();
 };
 
 };

src/CMakeLists.txt

@@ -1,6 +1,10 @@
 cmake_minimum_required(VERSION 3.5)
 project(QtAdvancedDockingSystem LANGUAGES CXX VERSION ${VERSION_SHORT})
-find_package(Qt5 5.5 COMPONENTS Core Gui Widgets REQUIRED)
+find_package(QT NAMES Qt6 Qt5 COMPONENTS Core REQUIRED)
+find_package(Qt${QT_VERSION_MAJOR} 5.5 COMPONENTS Core Gui Widgets REQUIRED)
+if (UNIX AND NOT APPLE)
+    include_directories(${Qt${QT_VERSION_MAJOR}Gui_PRIVATE_INCLUDE_DIRS})
+endif()
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
 if(BUILD_STATIC)
     set(CMAKE_STATIC_LIBRARY_SUFFIX "_static${CMAKE_STATIC_LIBRARY_SUFFIX}")
@@ -45,7 +49,8 @@ set(ads_HEADERS
     IconProvider.h
     DockComponentsFactory.h
 )
-if (UNIX)
+add_compile_options("$<$<CXX_COMPILER_ID:MSVC>:/utf-8>")
+if (UNIX AND NOT APPLE)
     set(ads_SRCS linux/FloatingWidgetTitleBar.cpp ${ads_SRCS})
     set(ads_HEADERS linux/FloatingWidgetTitleBar.h ${ads_HEADERS})
 endif()
@@ -56,8 +61,10 @@ else()
     add_library(qtadvanceddocking SHARED ${ads_SRCS} ${ads_HEADERS})
     target_compile_definitions(qtadvanceddocking PRIVATE ADS_SHARED_EXPORT)
 endif()
-target_link_libraries(qtadvanceddocking PUBLIC Qt5::Core Qt5::Gui Qt5::Widgets)
-set_target_properties(qtadvanceddocking PROPERTIES 
+target_link_libraries(qtadvanceddocking PUBLIC Qt${QT_VERSION_MAJOR}::Core 
+                                               Qt${QT_VERSION_MAJOR}::Gui 
+                                               Qt${QT_VERSION_MAJOR}::Widgets)
+set_target_properties(qtadvanceddocking PROPERTIES
     AUTOMOC ON
     AUTORCC ON
     CXX_STANDARD 14
@@ -76,13 +83,13 @@ write_basic_package_version_file(
     COMPATIBILITY SameMajorVersion
 )
 install(FILES ${ads_HEADERS}
-    DESTINATION include 
+    DESTINATION include
     COMPONENT headers
 )
-install(FILES 
+install(FILES
     "${CMAKE_SOURCE_DIR}/LICENSE"
     "${CMAKE_SOURCE_DIR}/gnu-lgpl-v2.1.md"
-    DESTINATION license 
+    DESTINATION license
     COMPONENT license
 )
 install(TARGETS qtadvanceddocking

src/DockAreaTabBar.cpp

@@ -180,11 +180,11 @@ void CDockAreaTabBar::setCurrentIndex(int index)
 		return;
     }
 
-    emit currentChanging(index);
+    Q_EMIT currentChanging(index);
 	d->CurrentIndex = index;
 	d->updateTabs();
 	updateGeometry();
-	emit currentChanged(index);
+	Q_EMIT currentChanged(index);
 }
 
 
@@ -206,7 +206,7 @@ void CDockAreaTabBar::insertTab(int Index, CDockWidgetTab* Tab)
 	connect(Tab, SIGNAL(moved(const QPoint&)), this, SLOT(onTabWidgetMoved(const QPoint&)));
 	connect(Tab, SIGNAL(elidedChanged(bool)), this, SIGNAL(elidedChanged(bool)));
 	Tab->installEventFilter(this);
-	emit tabInserted(Index);
+	Q_EMIT tabInserted(Index);
     if (Index <= d->CurrentIndex)
 	{
 		setCurrentIndex(d->CurrentIndex + 1);
@@ -266,7 +266,7 @@ void CDockAreaTabBar::removeTab(CDockWidgetTab* Tab)
 		}
 	}
 
-	emit removingTab(RemoveIndex);
+	Q_EMIT removingTab(RemoveIndex);
 	d->TabsLayout->removeWidget(Tab);
 	Tab->disconnect(this);
 	Tab->removeEventFilter(this);
@@ -320,7 +320,7 @@ void CDockAreaTabBar::onTabClicked()
 		return;
 	}
 	setCurrentIndex(index);
- 	emit tabBarClicked(index);
+ 	Q_EMIT tabBarClicked(index);
 }
 
 
@@ -409,7 +409,7 @@ void CDockAreaTabBar::onTabWidgetMoved(const QPoint& GlobalPos)
 		d->TabsLayout->removeWidget(MovingTab);
 		d->TabsLayout->insertWidget(toIndex, MovingTab);
         ADS_PRINT("tabMoved from " << fromIndex << " to " << toIndex);
-		emit tabMoved(fromIndex, toIndex);
+		Q_EMIT tabMoved(fromIndex, toIndex);
 		setCurrentIndex(toIndex);
 	}
 	else
@@ -432,7 +432,7 @@ void CDockAreaTabBar::closeTab(int Index)
 	{
 		return;
 	}
-	emit tabCloseRequested(Index);
+	Q_EMIT tabCloseRequested(Index);
 }
 
 
@@ -449,12 +449,12 @@ bool CDockAreaTabBar::eventFilter(QObject *watched, QEvent *event)
 	switch (event->type())
 	{
 	case QEvent::Hide:
-		 emit tabClosed(d->TabsLayout->indexOf(Tab));
+		 Q_EMIT tabClosed(d->TabsLayout->indexOf(Tab));
 		 updateGeometry();
 		 break;
 
 	case QEvent::Show:
-		 emit tabOpened(d->TabsLayout->indexOf(Tab));
+		 Q_EMIT tabOpened(d->TabsLayout->indexOf(Tab));
 		 updateGeometry();
 		 break;
 

src/DockAreaTabBar.h

@@ -58,7 +58,7 @@ private:
 	friend struct DockAreaTabBarPrivate;
 	friend class CDockAreaTitleBar;
 
-private slots:
+private Q_SLOTS:
 	void onTabClicked();
 	void onTabCloseRequested();
 	void onCloseOtherTabsRequested();
@@ -140,7 +140,7 @@ public:
 	 */
 	virtual QSize sizeHint() const override;
 
-public slots:
+public Q_SLOTS:
 	/**
 	 * This property sets the index of the tab bar's visible tab
 	 */
@@ -152,7 +152,7 @@ public slots:
 	 */
 	void closeTab(int Index);
 
-signals:
+Q_SIGNALS:
     /**
      * This signal is emitted when the tab bar's current tab is about to be changed. The new
      * current has the given index, or -1 if there isn't a new one.

src/DockAreaTitleBar.cpp

@@ -51,6 +51,7 @@
 #include "DockAreaTabBar.h"
 #include "IconProvider.h"
 #include "DockComponentsFactory.h"
+#include "DockFocusController.h"
 
 #include <iostream>
 
@@ -382,7 +383,7 @@ void CDockAreaTitleBar::onTabsMenuActionTriggered(QAction* Action)
 {
 	int Index = Action->data().toInt();
 	d->TabBar->setCurrentIndex(Index);
-	emit tabBarClicked(Index);
+	Q_EMIT tabBarClicked(Index);
 }
 
 
@@ -471,7 +472,8 @@ void CDockAreaTitleBar::mousePressEvent(QMouseEvent* ev)
 
 		if (CDockManager::testConfigFlag(CDockManager::FocusHighlighting))
 		{
-			d->TabBar->currentTab()->setFocus(Qt::OtherFocusReason);
+			//d->TabBar->currentTab()->setFocus(Qt::OtherFocusReason);
+			d->dockManager()->dockFocusController()->setDockWidgetTabFocused(d->TabBar->currentTab());
 		}
 		return;
 	}

src/DockAreaTitleBar.h

@@ -54,7 +54,7 @@ private:
 	DockAreaTitleBarPrivate* d; ///< private data (pimpl)
 	friend struct DockAreaTitleBarPrivate;
 
-private slots:
+private Q_SLOTS:
 	void onTabsMenuAboutToShow();
 	void onCloseButtonClicked();
 	void onUndockButtonClicked();
@@ -88,7 +88,7 @@ protected:
 	 */
 	virtual void contextMenuEvent(QContextMenuEvent *event) override;
 
-public slots:
+public Q_SLOTS:
 	/**
 	 * Call this slot to tell the title bar that it should update the tabs menu
 	 * the next time it is shown.
@@ -148,7 +148,7 @@ public:
 	 */
 	int indexOf(QWidget *widget) const;
 
-signals:
+Q_SIGNALS:
 	/**
 	 * This signal is emitted if a tab in the tab bar is clicked by the user
 	 * or if the user clicks on a tab item in the title bar tab menu.

src/DockAreaWidget.cpp

@@ -324,7 +324,6 @@ struct DockAreaWidgetPrivate
 		}
 	}
 };
-// struct DockAreaWidgetPrivate
 
 
 //============================================================================
@@ -379,7 +378,7 @@ CDockAreaWidget::CDockAreaWidget(CDockManager* DockManager, CDockContainerWidget
 	d->ContentsLayout = new DockAreaLayout(d->Layout);
 	if (d->DockManager)
 	{
-		emit d->DockManager->dockAreaCreated(this);
+		Q_EMIT d->DockManager->dockAreaCreated(this);
 	}
 }
 
@@ -605,11 +604,11 @@ void CDockAreaWidget::setCurrentIndex(int index)
 		return;
 	}
 
-    emit currentChanging(index);
+    Q_EMIT currentChanging(index);
     TabBar->setCurrentIndex(index);
 	d->ContentsLayout->setCurrentIndex(index);
 	d->ContentsLayout->currentWidget()->show();
-	emit currentChanged(index);
+	Q_EMIT currentChanged(index);
 }
 
 
@@ -809,18 +808,49 @@ CDockWidget* CDockAreaWidget::nextOpenDockWidget(CDockWidget* DockWidget) const
 	auto OpenDockWidgets = openedDockWidgets();
 	if (OpenDockWidgets.count() > 1 || (OpenDockWidgets.count() == 1 && OpenDockWidgets[0] != DockWidget))
 	{
-		CDockWidget* NextDockWidget;
 		if (OpenDockWidgets.last() == DockWidget)
 		{
-			NextDockWidget = OpenDockWidgets[OpenDockWidgets.count() - 2];
+			CDockWidget* NextDockWidget = OpenDockWidgets[OpenDockWidgets.count() - 2];
+			// search backwards for widget with tab
+			for (int i = OpenDockWidgets.count() - 2; i >= 0; --i)
+			{
+				auto dw = OpenDockWidgets[i];
+				if (!dw->features().testFlag(CDockWidget::NoTab))
+				{
+					return dw;
+				}
+			}
+
+			// return widget without tab
+			return NextDockWidget;
 		}
 		else
 		{
-			int NextIndex = OpenDockWidgets.indexOf(DockWidget) + 1;
-			NextDockWidget = OpenDockWidgets[NextIndex];
-		}
+			int IndexOfDockWidget = OpenDockWidgets.indexOf(DockWidget);
+			CDockWidget* NextDockWidget = OpenDockWidgets[IndexOfDockWidget + 1];
+			// search forwards for widget with tab
+			for (int i = IndexOfDockWidget + 1; i < OpenDockWidgets.count(); ++i)
+			{
+				auto dw = OpenDockWidgets[i];
+				if (!dw->features().testFlag(CDockWidget::NoTab))
+				{
+					return dw;
+				}
+			}
 
-		return NextDockWidget;
+			// search backwards for widget with tab
+			for (int i = IndexOfDockWidget - 1; i >= 0; --i)
+			{
+				auto dw = OpenDockWidgets[i];
+				if (!dw->features().testFlag(CDockWidget::NoTab))
+				{
+					return dw;
+				}
+			}
+
+			// return widget without tab
+			return NextDockWidget;
+		}
 	}
 	else
 	{
@@ -858,7 +888,7 @@ void CDockAreaWidget::toggleView(bool Open)
 {
 	setVisible(Open);
 
-	emit viewToggled(Open);
+	Q_EMIT viewToggled(Open);
 }
 
 
@@ -928,17 +958,20 @@ void CDockAreaWidget::closeArea()
 	// If there is only one single dock widget and this widget has the
 	// DeleteOnClose feature, then we delete the dock widget now
 	auto OpenDockWidgets = openedDockWidgets();
-	if (OpenDockWidgets.count() == 1 && OpenDockWidgets[0]->features().testFlag(CDockWidget::DockWidgetDeleteOnClose))
+    if (OpenDockWidgets.count() == 1 && OpenDockWidgets[0]->features().testFlag(CDockWidget::DockWidgetDeleteOnClose))
 	{
 		OpenDockWidgets[0]->closeDockWidgetInternal();
 	}
-	else
+    else
 	{
-		for (auto DockWidget : openedDockWidgets())
-		{
-			DockWidget->toggleView(false);
-		}
-	}
+        for (auto DockWidget : openedDockWidgets())
+        {
+            if (DockWidget->features().testFlag(CDockWidget::DockWidgetDeleteOnClose) && DockWidget->features().testFlag(CDockWidget::DockWidgetForceCloseWithArea))
+                DockWidget->closeDockWidgetInternal();
+            else
+                DockWidget->toggleView(false);
+        }
+    }
 }
 
 
@@ -971,7 +1004,19 @@ bool CDockAreaWidget::isCentralWidgetArea() const
 //============================================================================
 QSize CDockAreaWidget::minimumSizeHint() const
 {
-	return d->MinSizeHint.isValid() ? d->MinSizeHint : Super::minimumSizeHint();
+	if (!d->MinSizeHint.isValid())
+	{
+		return Super::minimumSizeHint();
+	}
+
+	if (d->TitleBar->isVisible())
+	{
+		return d->MinSizeHint + QSize(0, d->TitleBar->minimumSizeHint().height());
+	}
+	else
+	{
+		return d->MinSizeHint;
+	}
 }
 
 
@@ -985,6 +1030,21 @@ void CDockAreaWidget::onDockWidgetFeaturesChanged()
 }
 
 
+#ifdef Q_OS_WIN
+//============================================================================
+bool CDockAreaWidget::event(QEvent *e)
+{
+    switch (e->type())
+    {
+    case QEvent::PlatformSurface: return true;
+    default:
+        break;
+    }
+
+    return Super::event(e);
+}
+#endif
+
 } // namespace ads
 
 //---------------------------------------------------------------------------

src/DockAreaWidget.h

@@ -67,7 +67,7 @@ private:
 	friend class CDockManager;
 	void onDockWidgetFeaturesChanged();
 
-private slots:
+private Q_SLOTS:
 	void onTabCloseRequested(int Index);
 
 	/**
@@ -77,6 +77,17 @@ private slots:
 	void reorderDockWidget(int fromIndex, int toIndex);
 
 protected:
+
+#ifdef Q_OS_WIN
+	/**
+	 * Reimplements QWidget::event to handle QEvent::PlatformSurface
+	 * This is here to fix issue #294 Tab refresh problem with a QGLWidget
+	 * that exists since Qt version 5.12.7. So this function is here to
+	 * work around a Qt issue.
+	 */
+	virtual bool event(QEvent *event) override;
+#endif
+
 	/**
 	 * Inserts a dock widget into dock area.
 	 * All dockwidgets in the dock area tabified in a stacked layout with tabs.
@@ -138,7 +149,7 @@ protected:
 	 */
 	void markTitleBarMenuOutdated();
 
-protected slots:
+protected Q_SLOTS:
 	void toggleView(bool Open);
 
 public:
@@ -312,7 +323,7 @@ public:
      */
     bool isCentralWidgetArea() const;
 
-public slots:
+public Q_SLOTS:
 	/**
 	 * This activates the tab for the given tab index.
 	 * If the dock widget for the given tab is not visible, the this function
@@ -330,7 +341,7 @@ public slots:
 	 */
 	void closeOtherAreas();
 
-signals:
+Q_SIGNALS:
 	/**
 	 * This signal is emitted when user clicks on a tab at an index.
 	 */
@@ -356,7 +367,8 @@ signals:
 	 */
 	void viewToggled(bool Open);
 }; // class DockAreaWidget
-}
- // namespace ads
+} // namespace ads
+
+Q_DECLARE_OPERATORS_FOR_FLAGS(ads::CDockAreaWidget::DockAreaFlags)
 //-----------------------------------------------------------------------------
 #endif // DockAreaWidgetH

src/DockContainerWidget.cpp

@@ -284,13 +284,13 @@ public:
 	void emitDockAreasRemoved()
 	{
 		onVisibleDockAreaCountChanged();
-		emit _this->dockAreasRemoved();
+		Q_EMIT _this->dockAreasRemoved();
 	}
 
 	void emitDockAreasAdded()
 	{
 		onVisibleDockAreaCountChanged();
-		emit _this->dockAreasAdded();
+		Q_EMIT _this->dockAreasAdded();
 	}
 
 	/**
@@ -341,7 +341,7 @@ public:
 		CDockAreaWidget* DockArea = qobject_cast<CDockAreaWidget*>(_this->sender());
 		VisibleDockAreaCount += Visible ? 1 : -1;
 		onVisibleDockAreaCountChanged();
-		emit _this->dockAreaViewToggled(DockArea, Visible);
+		Q_EMIT _this->dockAreaViewToggled(DockArea, Visible);
 	}
 }; // struct DockContainerWidgetPrivate
 
@@ -917,15 +917,15 @@ bool DockContainerWidgetPrivate::restoreSplitter(CDockingStateReader& s,
 	{
 		QWidget* ChildNode = nullptr;
 		bool Result = true;
-		if (s.name() == "Splitter")
+        if (s.name() == QLatin1String("Splitter"))
 		{
 			Result = restoreSplitter(s, ChildNode, Testing);
 		}
-		else if (s.name() == "Area")
+        else if (s.name() == QLatin1String("Area"))
 		{
 			Result = restoreDockArea(s, ChildNode, Testing);
 		}
-		else if (s.name() == "Sizes")
+        else if (s.name() == QLatin1String("Sizes"))
 		{
 			QString sSizes = s.readElementText().trimmed();
             ADS_PRINT("Sizes: " << sSizes);
@@ -1026,7 +1026,7 @@ bool DockContainerWidgetPrivate::restoreDockArea(CDockingStateReader& s,
 
 	while (s.readNextStartElement())
 	{
-		if (s.name() != "Widget")
+        if (s.name() != QLatin1String("Widget"))
 		{
 			continue;
 		}
@@ -1089,12 +1089,12 @@ bool DockContainerWidgetPrivate::restoreChildNodes(CDockingStateReader& s,
 	bool Result = true;
 	while (s.readNextStartElement())
 	{
-		if (s.name() == "Splitter")
+        if (s.name() == QLatin1String("Splitter"))
 		{
 			Result = restoreSplitter(s, CreatedWidget, Testing);
             ADS_PRINT("Splitter");
 		}
-		else if (s.name() == "Area")
+        else if (s.name() == QLatin1String("Area"))
 		{
 			Result = restoreDockArea(s, CreatedWidget, Testing);
             ADS_PRINT("DockAreaWidget");
@@ -1207,7 +1207,7 @@ void DockContainerWidgetPrivate::dumpRecursive(int level, QWidget* widget)
 		std::cout << (const char*)buf
 			<< (DockArea->isHidden() ? " " : "v")
 			<< (DockArea->openDockWidgetsCount() > 0 ? " " : "c")
-			<< " DockArea" << std::endl;
+			<< " DockArea " << "[hs: " << DockArea->sizePolicy().horizontalStretch() << ", vs: " <<  DockArea->sizePolicy().verticalStretch() << "]" << std::endl;
 		buf.fill(' ', (level + 1) * 4);
 		for (int i = 0; i < DockArea->dockWidgetsCount(); ++i)
 		{
@@ -1253,7 +1253,6 @@ CDockAreaWidget* DockContainerWidgetPrivate::addDockWidgetToDockArea(DockWidgetA
 		{
 			adjustSplitterSizesOnInsertion(TargetAreaSplitter);
 		}
-
 	}
 	else
 	{
@@ -1273,8 +1272,7 @@ CDockAreaWidget* DockContainerWidgetPrivate::addDockWidgetToDockArea(DockWidgetA
 		}
 	}
 
-	appendDockAreas({NewDockArea});
-	emitDockAreasAdded();
+	addDockAreasToList({NewDockArea});
 	return NewDockArea;
 }
 
@@ -1567,8 +1565,9 @@ void CDockContainerWidget::dropFloatingWidget(CFloatingDockContainer* FloatingWi
 	}
 
 	if (Dropped)
-	{
-		FloatingWidget->deleteLater();
+	{ 
+		// Fix https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/issues/351
+		FloatingWidget->hideAndDeleteLater();
 
 		// If we dropped a floating widget with only one single dock widget, then we
 		// drop a top level widget that changes from floating to docked now
@@ -1626,6 +1625,21 @@ QList<CDockAreaWidget*> CDockContainerWidget::openedDockAreas() const
 }
 
 
+//============================================================================
+bool CDockContainerWidget::hasOpenDockAreas() const
+{
+	for (auto DockArea : d->DockAreas)
+	{
+		if (!DockArea->isHidden())
+		{
+			return true;
+		}
+	}
+
+	return false;
+}
+
+
 //============================================================================
 void CDockContainerWidget::saveState(QXmlStreamWriter& s) const
 {
@@ -1666,7 +1680,7 @@ bool CDockContainerWidget::restoreState(CDockingStateReader& s, bool Testing)
 	if (IsFloating)
 	{
         ADS_PRINT("Restore floating widget");
-		if (!s.readNextStartElement() || s.name() != "Geometry")
+        if (!s.readNextStartElement() || s.name() != QLatin1String("Geometry"))
 		{
 			return false;
 		}
@@ -1681,7 +1695,10 @@ bool CDockContainerWidget::restoreState(CDockingStateReader& s, bool Testing)
 		if (!Testing)
 		{
 			CFloatingDockContainer* FloatingWidget = floatingWidget();
-			FloatingWidget->restoreGeometry(Geometry);
+			if (FloatingWidget)
+			{
+				FloatingWidget->restoreGeometry(Geometry);
+			}
 		}
 	}
 

src/DockContainerWidget.h

@@ -216,6 +216,13 @@ public:
 	 */
 	QList<CDockAreaWidget*> openedDockAreas() const;
 
+	/**
+	 * This function returns true, if the container has open dock areas.
+	 * This functions is a little bit faster than calling openedDockAreas().isEmpty()
+	 * because it returns as soon as it finds an open dock area
+	 */
+	bool hasOpenDockAreas() const;
+
     /**
      * This function returns true if this dock area has only one single
      * visible dock widget.
@@ -265,7 +272,7 @@ public:
 	 */
 	void closeOtherAreas(CDockAreaWidget* KeepOpenArea);
 
-signals:
+Q_SIGNALS:
 	/**
 	 * This signal is emitted if one or multiple dock areas has been added to
 	 * the internal list of dock areas.

src/DockFocusController.cpp

@@ -16,6 +16,7 @@
 #include <QPointer>
 #include <QApplication>
 #include <QAbstractButton>
+#include <QWindow>
 
 #include "DockWidget.h"
 #include "DockAreaWidget.h"
@@ -31,6 +32,8 @@
 
 namespace ads
 {
+static const char* const FocusedDockWidgetProperty = "FocusedDockWidget";
+
 /**
  * Private data class of CDockFocusController class (pimpl)
  */
@@ -56,8 +59,8 @@ struct DockFocusControllerPrivate
 	 * the dock area that it belongs to
 	 */
 	void updateDockWidgetFocus(CDockWidget* DockWidget);
-};
-// struct DockFocusControllerPrivate
+}; // struct DockFocusControllerPrivate
+
 
 
 //===========================================================================
@@ -115,6 +118,17 @@ void DockFocusControllerPrivate::updateDockWidgetFocus(CDockWidget* DockWidget)
 		return;
 	}
 
+	QWindow* Window = nullptr;
+	auto DockContainer = DockWidget->dockContainer();
+	if (DockContainer)
+	{
+		Window = DockContainer->window()->windowHandle();
+	}
+
+	if (Window)
+	{
+        Window->setProperty(FocusedDockWidgetProperty, QVariant::fromValue(QPointer<CDockWidget>(DockWidget)));
+	}
 	CDockAreaWidget* NewFocusedDockArea = nullptr;
 	if (FocusedDockWidget)
 	{
@@ -139,31 +153,36 @@ void DockFocusControllerPrivate::updateDockWidgetFocus(CDockWidget* DockWidget)
 	}
 
 
-    auto NewFloatingWidget = FocusedDockWidget->dockContainer()->floatingWidget();
+
+    CFloatingDockContainer* NewFloatingWidget = nullptr;
+    DockContainer = FocusedDockWidget->dockContainer();
+    if (DockContainer)
+    {
+    	NewFloatingWidget = DockContainer->floatingWidget();
+    }
+
     if (NewFloatingWidget)
     {
-    	NewFloatingWidget->setProperty("FocusedDockWidget", QVariant::fromValue(DockWidget));
+        NewFloatingWidget->setProperty(FocusedDockWidgetProperty, QVariant::fromValue(QPointer<CDockWidget>(DockWidget)));
     }
 
 
 #ifdef Q_OS_LINUX
 	// This code is required for styling the floating widget titlebar for linux
 	// depending on the current focus state
-    if (FloatingWidget == NewFloatingWidget)
-    {
-        return;
-    }
+	if (FloatingWidget != NewFloatingWidget)
+	{
+		if (FloatingWidget)
+		{
+			updateFloatingWidgetFocusStyle(FloatingWidget, false);
+		}
+		FloatingWidget = NewFloatingWidget;
 
-    if (FloatingWidget)
-    {
-        updateFloatingWidgetFocusStyle(FloatingWidget, false);
-    }
-    FloatingWidget = NewFloatingWidget;
-
-    if (FloatingWidget)
-    {
-        updateFloatingWidgetFocusStyle(FloatingWidget, true);
-    }
+		if (FloatingWidget)
+		{
+			updateFloatingWidgetFocusStyle(FloatingWidget, true);
+		}
+	}
 #endif
 
     if (old == DockWidget && !ForceFocusChangedSignal)
@@ -174,7 +193,7 @@ void DockFocusControllerPrivate::updateDockWidgetFocus(CDockWidget* DockWidget)
     ForceFocusChangedSignal = false;
     if (DockWidget->isVisible())
     {
-    	emit DockManager->focusedDockWidgetChanged(old, DockWidget);
+    	Q_EMIT DockManager->focusedDockWidgetChanged(old, DockWidget);
     }
     else
     {
@@ -193,7 +212,7 @@ void CDockFocusController::onDockWidgetVisibilityChanged(bool Visible)
     disconnect(Sender, SIGNAL(visibilityChanged(bool)), this, SLOT(onDockWidgetVisibilityChanged(bool)));
     if (DockWidget && Visible)
 	{
-        emit d->DockManager->focusedDockWidgetChanged(d->OldFocusedDockWidget, DockWidget);
+        Q_EMIT d->DockManager->focusedDockWidgetChanged(d->OldFocusedDockWidget, DockWidget);
 	}
 }
 
@@ -206,6 +225,8 @@ CDockFocusController::CDockFocusController(CDockManager* DockManager) :
 	d->DockManager = DockManager;
 	connect(QApplication::instance(), SIGNAL(focusChanged(QWidget*, QWidget*)),
 			this, SLOT(onApplicationFocusChanged(QWidget*, QWidget*)));
+	connect(QApplication::instance(), SIGNAL(focusWindowChanged(QWindow*)),
+			this, SLOT(onFocusWindowChanged(QWindow*)));
 	connect(d->DockManager, SIGNAL(stateRestored()), SLOT(onStateRestored()));
 }
 
@@ -216,9 +237,35 @@ CDockFocusController::~CDockFocusController()
 }
 
 
+//============================================================================
+void CDockFocusController::onFocusWindowChanged(QWindow *focusWindow)
+{
+	if (!focusWindow)
+	{
+		return;
+	}
+
+    auto vDockWidget = focusWindow->property(FocusedDockWidgetProperty);
+	if (!vDockWidget.isValid())
+	{
+		return;
+	}
+
+    auto DockWidget = vDockWidget.value<QPointer<CDockWidget>>();
+	if (!DockWidget)
+	{
+		return;
+	}
+
+	d->updateDockWidgetFocus(DockWidget);
+}
+
+
 //===========================================================================
 void CDockFocusController::onApplicationFocusChanged(QWidget* focusedOld, QWidget* focusedNow)
 {
+	Q_UNUSED(focusedOld);
+
 	if (d->DockManager->isRestoringState())
 	{
 		return;
@@ -231,43 +278,7 @@ void CDockFocusController::onApplicationFocusChanged(QWidget* focusedOld, QWidge
 		return;
 	}
 
-	// If the close button in another tab steals the focus from the current
-	// active dock widget content, i.e. if the user clicks its close button,
-	// then we immediately give the focus back to the previous focused widget
-	// focusedOld
-	if (CDockManager::testConfigFlag(CDockManager::AllTabsHaveCloseButton))
-	{
-		auto OtherDockWidgetTab = internal::findParent<CDockWidgetTab*>(focusedNow);
-		if (OtherDockWidgetTab && focusedOld)
-		{
-			focusedOld->setFocus();
-			return;
-		}
-	}
-
-    CDockWidget* DockWidget = nullptr;
-	auto DockWidgetTab = qobject_cast<CDockWidgetTab*>(focusedNow);
-	if (DockWidgetTab)
-	{
-		DockWidget = DockWidgetTab->dockWidget();      
-        // If the DockWidgetTab "steals" the focus from a widget in the same
-        // DockWidget, then we immediately give the focus back to the previous
-        // focused widget focusedOld
-        if (focusedOld)
-        {
-            auto OldFocusedDockWidget = internal::findParent<CDockWidget*>(focusedOld);
-            if (OldFocusedDockWidget && OldFocusedDockWidget == DockWidget)
-            {
-                focusedOld->setFocus();
-            }
-        }
-	}
-
-	if (!DockWidget)
-	{
-		DockWidget = qobject_cast<CDockWidget*>(focusedNow);
-	}
-
+    CDockWidget* DockWidget = qobject_cast<CDockWidget*>(focusedNow);
 	if (!DockWidget)
 	{
 		DockWidget = internal::findParent<CDockWidget*>(focusedNow);
@@ -289,6 +300,17 @@ void CDockFocusController::onApplicationFocusChanged(QWidget* focusedOld, QWidge
 }
 
 
+//===========================================================================
+void CDockFocusController::setDockWidgetTabFocused(CDockWidgetTab* Tab)
+{
+	auto DockWidget = Tab->dockWidget();
+	if (DockWidget)
+	{
+		d->updateDockWidgetFocus(DockWidget);
+	}
+}
+
+
 //===========================================================================
 void CDockFocusController::setDockWidgetFocused(CDockWidget* focusedNow)
 {
@@ -316,7 +338,7 @@ void CDockFocusController::onFocusedDockAreaViewToggled(bool Open)
 		return;
 	}
 
-	CDockManager::setWidgetFocus(OpenedDockAreas[0]->currentDockWidget()->tabWidget());
+	d->updateDockWidgetFocus(OpenedDockAreas[0]->currentDockWidget());
 }
 
 
@@ -344,7 +366,7 @@ void CDockFocusController::notifyWidgetOrAreaRelocation(QWidget* DroppedWidget)
     }
 
     d->ForceFocusChangedSignal = true;
-    CDockManager::setWidgetFocus(DockWidget->tabWidget());
+    CDockManager::setWidgetFocus(DockWidget);
 }
 
 
@@ -356,18 +378,17 @@ void CDockFocusController::notifyFloatingWidgetDrop(CFloatingDockContainer* Floa
 		return;
 	}
 
-	auto vDockWidget = FloatingWidget->property("FocusedDockWidget");
+    auto vDockWidget = FloatingWidget->property(FocusedDockWidgetProperty);
 	if (!vDockWidget.isValid())
 	{
 		return;
 	}
 
-	auto DockWidget = vDockWidget.value<CDockWidget*>();
+    auto DockWidget = vDockWidget.value<QPointer<CDockWidget>>();
 	if (DockWidget)
 	{
-		d->FocusedDockWidget = nullptr;
 		DockWidget->dockAreaWidget()->setCurrentDockWidget(DockWidget);
-		CDockManager::setWidgetFocus(DockWidget->tabWidget());
+		CDockManager::setWidgetFocus(DockWidget);
 	}
 }
 
@@ -381,6 +402,13 @@ void CDockFocusController::onStateRestored()
 	}
 }
 
+
+//==========================================================================
+CDockWidget* CDockFocusController::focusedDockWidget() const
+{
+	return d->FocusedDockWidget.data();
+}
+
 } // namespace ads
 
 //---------------------------------------------------------------------------

src/DockFocusController.h

@@ -30,8 +30,9 @@ private:
 	DockFocusControllerPrivate* d; ///< private data (pimpl)
     friend struct DockFocusControllerPrivate;
 
-private slots:
+private Q_SLOTS:
 	void onApplicationFocusChanged(QWidget *old, QWidget *now);
+	void onFocusWindowChanged(QWindow *focusWindow);
 	void onFocusedDockAreaViewToggled(bool Open);
 	void onStateRestored();
 	void onDockWidgetVisibilityChanged(bool Visible);
@@ -48,21 +49,6 @@ public:
 	 */
 	virtual ~CDockFocusController();
 
-	/**
-	 * Helper function to set focus depending on the configuration of the
-	 * FocusStyling flag
-	 */
-	template <class QWidgetPtr>
-	static void setWidgetFocus(QWidgetPtr widget)
-	{
-		if (!CDockManager::testConfigFlag(CDockManager::FocusHighlighting))
-		{
-			return;
-		}
-
-		widget->setFocus(Qt::OtherFocusReason);
-	}
-
 	/**
 	 * A container needs to call this function if a widget has been dropped
 	 * into it
@@ -77,7 +63,19 @@ public:
 	 */
 	void notifyFloatingWidgetDrop(CFloatingDockContainer* FloatingWidget);
 
-public slots:
+	/**
+	 * Returns the dock widget that has focus style in the ui or a nullptr if
+	 * not dock widget is painted focused.
+	 */
+	CDockWidget* focusedDockWidget() const;
+
+	/**
+	 * Request focus highlighting for the given dock widget assigned to the tab
+	 * given in Tab parameter
+	 */
+	void setDockWidgetTabFocused(CDockWidgetTab* Tab);
+
+public Q_SLOTS:
 	/**
 	 * Request a focus change to the given dock widget
 	 */

src/DockManager.cpp

@@ -55,6 +55,7 @@
 #include "DockingStateReader.h"
 #include "DockAreaTitleBar.h"
 #include "DockFocusController.h"
+#include "DockSplitter.h"
 
 #ifdef Q_OS_LINUX
 #include "linux/FloatingWidgetTitleBar.h"
@@ -249,7 +250,7 @@ bool DockManagerPrivate::restoreStateFromXml(const QByteArray &state,  int versi
     }
     CDockingStateReader s(state);
     s.readNextStartElement();
-    if (s.name() != "QtAdvancedDockingSystem")
+    if (s.name() != QLatin1String("QtAdvancedDockingSystem"))
     {
     	return false;
     }
@@ -279,10 +280,31 @@ bool DockManagerPrivate::restoreStateFromXml(const QByteArray &state,  int versi
     int  DockContainers = s.attributes().value("Containers").toInt();
 #endif
     ADS_PRINT(DockContainers);
+
+    if (CentralWidget)
+    {
+		const auto CentralWidgetAttribute = s.attributes().value("CentralWidget");
+		// If we have a central widget but a state without central widget, then
+		// something is wrong.
+		if (CentralWidgetAttribute.isEmpty())
+		{
+			qWarning() << "Dock manager has central widget but saved state does not have central widget.";
+			return false;
+		}
+
+		// If the object name of the central widget does not match the name of the
+		// saved central widget, the something is wrong
+		if (CentralWidget->objectName() != CentralWidgetAttribute.toString())
+		{
+			qWarning() << "Object name of central widget does not match name of central widget in saved state.";
+			return false;
+		}
+    }
+
     int DockContainerCount = 0;
     while (s.readNextStartElement())
     {
-    	if (s.name() == "Container")
+        if (s.name() == QLatin1String("Container"))
     	{
     		Result = restoreContainer(DockContainerCount, s, Testing);
 			if (!Result)
@@ -321,7 +343,7 @@ void DockManagerPrivate::restoreDockWidgetsOpenState()
     	if (DockWidget->property(internal::DirtyProperty).toBool())
     	{
     		DockWidget->flagAsUnassigned();
-            emit DockWidget->viewToggled(false);
+            Q_EMIT DockWidget->viewToggled(false);
     	}
     	else
     	{
@@ -405,7 +427,6 @@ bool DockManagerPrivate::restoreState(const QByteArray& State, int version)
     	return false;
     }
 
-    CentralWidget = nullptr;
     // Hide updates of floating widgets from use
     hideFloatingWidgets();
     markDockWidgetsDirty();
@@ -419,6 +440,7 @@ bool DockManagerPrivate::restoreState(const QByteArray& State, int version)
     restoreDockWidgetsOpenState();
     restoreDockAreasIndices();
     emitTopLevelEvents();
+    _this->dumpLayout();
 
     return true;
 }
@@ -483,6 +505,20 @@ CDockManager::CDockManager(QWidget *parent) :
 //============================================================================
 CDockManager::~CDockManager()
 {
+    // fix memory leaks, see https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/issues/307
+    std::vector<ads::CDockAreaWidget*> areas;
+    for ( int i = 0; i != dockAreaCount(); ++i )
+    {
+        areas.push_back( dockArea(i) );
+    }
+    for ( auto area : areas )
+    {
+        for ( auto widget : area->dockWidgets() )
+            delete widget;
+
+        delete area;
+    }
+
 	auto FloatingWidgets = d->FloatingWidgets;
 	for (auto FloatingWidget : FloatingWidgets)
 	{
@@ -560,7 +596,7 @@ bool CDockManager::eventFilter(QObject *obj, QEvent *e)
 void CDockManager::registerFloatingWidget(CFloatingDockContainer* FloatingWidget)
 {
 	d->FloatingWidgets.append(FloatingWidget);
-	emit floatingWidgetCreated(FloatingWidget);
+	Q_EMIT floatingWidgetCreated(FloatingWidget);
     ADS_PRINT("d->FloatingWidgets.count() " << d->FloatingWidgets.count());
 }
 
@@ -636,6 +672,10 @@ QByteArray CDockManager::saveState(int version) const
 		s.writeAttribute("Version", QString::number(CurrentVersion));
 		s.writeAttribute("UserVersion", QString::number(version));
 		s.writeAttribute("Containers", QString::number(d->Containers.count()));
+		if (d->CentralWidget)
+		{
+			s.writeAttribute("CentralWidget", d->CentralWidget->objectName());
+		}
 		for (auto Container : d->Containers)
 		{
 			Container->saveState(s);
@@ -673,14 +713,14 @@ bool CDockManager::restoreState(const QByteArray &state, int version)
 		hide();
 	}
 	d->RestoringState = true;
-	emit restoringState();
+	Q_EMIT restoringState();
 	bool Result = d->restoreState(state, version);
 	d->RestoringState = false;
 	if (!IsHidden)
 	{
 		show();
 	}
-	emit stateRestored();
+	Q_EMIT stateRestored();
 	return Result;
 }
 
@@ -706,6 +746,7 @@ CFloatingDockContainer* CDockManager::addDockWidgetFloating(CDockWidget* Dockwid
 	{
 		d->UninitializedFloatingWidgets.append(FloatingWidget);
 	}
+	Q_EMIT dockWidgetAdded(Dockwidget);
 	return FloatingWidget;
 }
 
@@ -721,7 +762,12 @@ void CDockManager::showEvent(QShowEvent *event)
 
 	for (auto FloatingWidget : d->UninitializedFloatingWidgets)
 	{
-		FloatingWidget->show();
+		// Check, if someone closed a floating dock widget before the dock
+		// manager is shown
+		if (FloatingWidget->dockContainer()->hasOpenDockAreas())
+		{
+			FloatingWidget->show();
+		}
 	}
 	d->UninitializedFloatingWidgets.clear();
 }
@@ -732,7 +778,10 @@ CDockAreaWidget* CDockManager::addDockWidget(DockWidgetArea area,
 	CDockWidget* Dockwidget, CDockAreaWidget* DockAreaWidget)
 {
 	d->DockWidgetsMap.insert(Dockwidget->objectName(), Dockwidget);
-	return CDockContainerWidget::addDockWidget(area, Dockwidget, DockAreaWidget);
+	auto Container = DockAreaWidget ? DockAreaWidget->dockContainer(): this;
+	auto AreaOfAddedDockWidget = Container->addDockWidget(area, Dockwidget, DockAreaWidget);
+	Q_EMIT dockWidgetAdded(Dockwidget);
+	return AreaOfAddedDockWidget;
 }
 
 
@@ -773,11 +822,11 @@ CDockWidget* CDockManager::findDockWidget(const QString& ObjectName) const
 //============================================================================
 void CDockManager::removeDockWidget(CDockWidget* Dockwidget)
 {
-	emit dockWidgetAboutToBeRemoved(Dockwidget);
+	Q_EMIT dockWidgetAboutToBeRemoved(Dockwidget);
 	d->DockWidgetsMap.remove(Dockwidget->objectName());
 	CDockContainerWidget::removeDockWidget(Dockwidget);
 	Dockwidget->setDockManager(nullptr);
-	emit dockWidgetRemoved(Dockwidget);
+	Q_EMIT dockWidgetRemoved(Dockwidget);
 }
 
 //============================================================================
@@ -791,7 +840,7 @@ QMap<QString, CDockWidget*> CDockManager::dockWidgetsMap() const
 void CDockManager::addPerspective(const QString& UniquePrespectiveName)
 {
 	d->Perspectives.insert(UniquePrespectiveName, saveState());
-	emit perspectiveListChanged();
+	Q_EMIT perspectiveListChanged();
 }
 
 
@@ -813,8 +862,8 @@ void CDockManager::removePerspectives(const QStringList& Names)
 
 	if (Count)
 	{
-		emit perspectivesRemoved();
-		emit perspectiveListChanged();
+		Q_EMIT perspectivesRemoved();
+		Q_EMIT perspectiveListChanged();
 	}
 }
 
@@ -835,9 +884,9 @@ void CDockManager::openPerspective(const QString& PerspectiveName)
 		return;
 	}
 
-	emit openingPerspective(PerspectiveName);
+	Q_EMIT openingPerspective(PerspectiveName);
 	restoreState(Iterator.value());
-	emit perspectiveOpened(PerspectiveName);
+	Q_EMIT perspectiveOpened(PerspectiveName);
 }
 
 
@@ -882,6 +931,8 @@ void CDockManager::loadPerspectives(QSettings& Settings)
 	}
 
 	Settings.endArray();
+	Q_EMIT perspectiveListChanged();
+	Q_EMIT perspectiveListLoaded();
 }
 
 
@@ -901,10 +952,20 @@ CDockAreaWidget* CDockManager::setCentralWidget(CDockWidget* widget)
 		return nullptr;
 	}
 
-	// Setting a new central widget is now allowed if there is alread a central
-	// widget
+	// Setting a new central widget is now allowed if there is already a central
+	// widget or if there are already other dock widgets
 	if (d->CentralWidget)
 	{
+		qWarning("Setting a central widget not possible because there is already a central widget.");
+		return nullptr;
+	}
+
+	// Setting a central widget is now allowed if there are already other
+	// dock widgets.
+	if (!d->DockWidgetsMap.isEmpty())
+	{
+		qWarning("Setting a central widget not possible - the central widget need to be the first "
+			"dock widget that is added to the dock manager.");
 		return nullptr;
 	}
 
@@ -1042,6 +1103,55 @@ void CDockManager::setDockWidgetFocused(CDockWidget* DockWidget)
 }
 
 
+//===========================================================================
+CDockWidget* CDockManager::focusedDockWidget() const
+{
+	if (!d->FocusController)
+	{
+		return nullptr;
+	}
+	else
+	{
+		return d->FocusController->focusedDockWidget();
+	}
+}
+
+//===========================================================================
+QList<int> CDockManager::splitterSizes(CDockAreaWidget *ContainedArea) const
+{
+    if (ContainedArea)
+    {
+        auto Splitter = internal::findParent<CDockSplitter*>(ContainedArea);
+        if (Splitter)
+        {
+            return Splitter->sizes();
+        }
+    }
+    return QList<int>();
+}
+
+//===========================================================================
+void CDockManager::setSplitterSizes(CDockAreaWidget *ContainedArea, const QList<int>& sizes)
+{
+    if (!ContainedArea)
+    {
+        return;
+    }
+
+    auto Splitter = internal::findParent<CDockSplitter*>(ContainedArea);
+    if (Splitter && Splitter->count() == sizes.count())
+    {
+        Splitter->setSizes(sizes);
+    }
+}
+
+
+//===========================================================================
+CDockFocusController* CDockManager::dockFocusController() const
+{
+	return d->FocusController;
+}
+
 } // namespace ads
 
 //---------------------------------------------------------------------------

src/DockManager.h

@@ -53,6 +53,7 @@ struct DockWidgetTabPrivate;
 struct DockAreaWidgetPrivate;
 class CIconProvider;
 class CDockComponentsFactory;
+class CDockFocusController;
 
 /**
  * The central dock manager that maintains the complete docking system.
@@ -134,12 +135,18 @@ protected:
 	 */
 	void notifyFloatingWidgetDrop(CFloatingDockContainer* FloatingWidget);
 
-
 	/**
 	 * Show the floating widgets that has been created floating
 	 */
 	virtual void showEvent(QShowEvent *event) override;
 
+	/**
+	 * Acces for the internal dock focus controller.
+	 * This function only returns a valid object, if the FocusHighlighting
+	 * flag is set.
+	 */
+	CDockFocusController* dockFocusController() const;
+
 public:
 	using Super = CDockContainerWidget;
 
@@ -188,6 +195,7 @@ public:
         FloatingContainerForceQWidgetTitleBar = 0x1000000,//!< Linux only ! Forces all FloatingContainer to use a QWidget based title bar.
 														 //!< If neither this nor FloatingContainerForceNativeTitleBar is set (the default) native titlebars are used except on known bad systems.
 														 //! Users can overwrite this by setting the environment variable ADS_UseNativeTitle to "1" or "0".
+		MiddleMouseButtonClosesTab = 0x2000000, //! If the flag is set, the user can use the mouse middle button to close the tab under the mouse
 
         DefaultDockAreaButtons = DockAreaHasCloseButton
 							   | DockAreaHasUndockButton
@@ -398,9 +406,12 @@ public:
      * movable, floatable or closable and the titlebar of the central
      * dock area is not visible.
      * If the given widget could be set as central widget, the function returns
-     * the created cok area. If the widget could not be set, because there
+     * the created dock area. If the widget could not be set, because there
      * is already a central widget, this function returns a nullptr.
      * To clear the central widget, pass a nullptr to the function.
+     * \note Setting a central widget is only possible if no other dock widgets
+     * have been registered before. That means, this function should be the
+     * first function that you call before you add other dock widgets.
      * \retval != 0 The dock area that contains the central widget
      * \retval nullptr Indicates that the given widget can not be set as central
      *         widget because there is already a central widget.
@@ -476,7 +487,34 @@ public:
 	bool eventFilter(QObject *obj, QEvent *e) override;
 #endif
 
-public slots:
+	/**
+	 * Returns the dock widget that has focus style in the ui or a nullptr if
+	 * not dock widget is painted focused.
+	 * If the flag FocusHighlighting is disabled, this function always returns
+	 * nullptr.
+	 */
+	CDockWidget* focusedDockWidget() const;
+
+    /**
+     * Returns the sizes of the splitter that contains the dock area.
+     *
+     * If there is no splitter that contains the area, an empty list will be
+     * returned.
+     */
+    QList<int> splitterSizes(CDockAreaWidget *ContainedArea) const;
+
+    /**
+     * Update the sizes of a splitter
+     * Programmatically updates the sizes of a given splitter by calling
+     * QSplitter::setSizes(). The splitter will be the splitter that
+     * contains the supplied dock area widget. If there is not splitter
+     * that contains the dock area, or the sizes supplied does not match
+     * the number of children of the splitter, this method will have no
+     * effect.
+     */
+    void setSplitterSizes(CDockAreaWidget *ContainedArea, const QList<int>& sizes);
+
+public Q_SLOTS:
 	/**
 	 * Opens the perspective with the given name.
 	 */
@@ -489,12 +527,19 @@ public slots:
 	 */
 	void setDockWidgetFocused(CDockWidget* DockWidget);
 
-signals:
+Q_SIGNALS:
 	/**
-	 * This signal is emitted if the list of perspectives changed
+	 * This signal is emitted if the list of perspectives changed.
+	 * The list of perspectives changes if perspectives are added, removed
+	 * or if the perspective list has been loaded
 	 */
 	void perspectiveListChanged();
 
+	/**
+	 * This signal is emitted if the perspective list has been loaded
+	 */
+	void perspectiveListLoaded();
+
 	/**
 	 * This signal is emitted if perspectives have been removed
 	 */
@@ -544,6 +589,12 @@ signals:
      */
     void dockAreaCreated(ads::CDockAreaWidget* DockArea);
 
+    /**
+     * This signal is emitted if a dock widget has been added to this
+     * dock manager instance.
+     */
+    void dockWidgetAdded(ads::CDockWidget* DockWidget);
+
     /**
      * This signal is emitted just before the given dock widget is removed
      * from the dock manager
@@ -566,5 +617,7 @@ signals:
     void focusedDockWidgetChanged(ads::CDockWidget* old, ads::CDockWidget* now);
 }; // class DockManager
 } // namespace ads
+
+Q_DECLARE_OPERATORS_FOR_FLAGS(ads::CDockManager::ConfigFlags)
 //-----------------------------------------------------------------------------
 #endif // DockManagerH

src/DockOverlay.cpp

@@ -806,10 +806,15 @@ void CDockOverlayCross::setIconColors(const QString& Colors)
 		{"Arrow", CDockOverlayCross::ArrowColor},
 		{"Shadow", CDockOverlayCross::ShadowColor}};
 
-	auto ColorList = Colors.split(' ', QString::SkipEmptyParts);
+#if (QT_VERSION < QT_VERSION_CHECK(5, 14, 0))
+    auto SkipEmptyParts = QString::SkipEmptyParts;
+#else
+    auto SkipEmptyParts = Qt::SkipEmptyParts;
+#endif
+    auto ColorList = Colors.split(' ', SkipEmptyParts);
 	for (const auto& ColorListEntry : ColorList)
 	{
-		auto ComponentColor = ColorListEntry.split('=', QString::SkipEmptyParts);
+        auto ComponentColor = ColorListEntry.split('=', SkipEmptyParts);
 		int Component = ColorCompenentStringMap.value(ComponentColor[0], -1);
 		if (Component < 0)
 		{

src/DockSplitter.cpp

@@ -31,7 +31,7 @@
 
 #include <QDebug>
 #include <QChildEvent>
-
+#include <QVariant>
 #include "DockAreaWidget.h"
 
 namespace ads
@@ -52,7 +52,7 @@ CDockSplitter::CDockSplitter(QWidget *parent)
 	: QSplitter(parent),
 	  d(new DockSplitterPrivate(this))
 {
-	setProperty("ads-splitter", true);
+    setProperty("ads-splitter", QVariant(true));
 	setChildrenCollapsible(false);
 }
 

src/DockWidget.cpp

@@ -66,6 +66,12 @@ namespace ads
  */
 struct DockWidgetPrivate
 {
+	struct WidgetFactory 
+	{
+		CDockWidget::FactoryFunc createWidget;
+		CDockWidget::eInsertMode insertMode;
+	};	
+	
 	CDockWidget* _this = nullptr;
 	QBoxLayout* Layout = nullptr;
 	QWidget* Widget = nullptr;
@@ -84,7 +90,8 @@ struct DockWidgetPrivate
 	bool IsFloatingTopLevel = false;
 	QList<QAction*> TitleBarActions;
 	CDockWidget::eMinimumSizeHintMode MinimumSizeHintMode = CDockWidget::MinimumSizeHintFromDockWidget;
-
+	WidgetFactory* Factory = nullptr;
+	
 	/**
 	 * Private data constructor
 	 */
@@ -116,6 +123,12 @@ struct DockWidgetPrivate
 	 * Setup the main scroll area
 	 */
 	void setupScrollArea();
+	
+	/**
+	 * Creates the content widget with the registered widget factory and
+	 * returns true on success.
+	 */
+	bool createWidgetFromFactory();
 };
 // struct DockWidgetPrivate
 
@@ -130,10 +143,23 @@ DockWidgetPrivate::DockWidgetPrivate(CDockWidget* _public) :
 //============================================================================
 void DockWidgetPrivate::showDockWidget()
 {
+	if (!Widget)
+	{
+		if (!createWidgetFromFactory())
+		{
+			Q_ASSERT(!Features.testFlag(CDockWidget::DeleteContentOnClose)
+					 && "DeleteContentOnClose flag was set, but the widget "
+						"factory is missing or it doesn't return a valid QWidget.");
+			return;	
+		}
+	}
+	
 	if (!DockArea)
 	{
 		CFloatingDockContainer* FloatingWidget = new CFloatingDockContainer(_this);
-		FloatingWidget->resize(_this->size());
+		// We use the size hint of the content widget to provide a good
+		// initial size
+		FloatingWidget->resize(Widget ? Widget->sizeHint() : _this->sizeHint());
 		TabWidget->show();
 		FloatingWidget->show();
 	}
@@ -165,6 +191,12 @@ void DockWidgetPrivate::hideDockWidget()
 {
 	TabWidget->hide();
 	updateParentDockArea();
+	
+	if (Features.testFlag(CDockWidget::DeleteContentOnClose))
+	{
+		Widget->deleteLater();
+		Widget = nullptr;
+	}
 }
 
 
@@ -218,6 +250,30 @@ void DockWidgetPrivate::setupScrollArea()
 }
 
 
+//============================================================================
+bool DockWidgetPrivate::createWidgetFromFactory()
+{
+	if (!Features.testFlag(CDockWidget::DeleteContentOnClose)) 
+	{
+		return false;
+	}
+	
+	if (!Factory)
+	{
+		return false;
+	}
+	
+	QWidget* w = Factory->createWidget(_this);
+	if (!w)
+	{
+		return false;
+	}
+	
+	_this->setWidget(w, Factory->insertMode);
+	return true;
+}
+
+
 //============================================================================
 CDockWidget::CDockWidget(const QString &title, QWidget *parent) :
 	QFrame(parent),
@@ -288,6 +344,17 @@ void CDockWidget::setWidget(QWidget* widget, eInsertMode InsertMode)
 	d->Widget->setProperty("dockWidgetContent", true);
 }
 
+//============================================================================
+void CDockWidget::setWidgetFactory(FactoryFunc createWidget, eInsertMode insertMode)
+{
+	if (d->Factory)
+	{
+		delete d->Factory;
+	}
+
+	d->Factory = new DockWidgetPrivate::WidgetFactory { createWidget, insertMode };
+}
+
 
 //============================================================================
 QWidget* CDockWidget::takeWidget()
@@ -338,7 +405,7 @@ void CDockWidget::setFeatures(DockWidgetFeatures features)
 		return;
 	}
 	d->Features = features;
-	emit featuresChanged(d->Features);
+	Q_EMIT featuresChanged(d->Features);
 	d->TabWidget->onDockWidgetFeaturesChanged();
 	if(CDockAreaWidget* DockArea = dockAreaWidget())
 		DockArea->onDockWidgetFeaturesChanged();
@@ -530,7 +597,8 @@ void CDockWidget::toggleViewInternal(bool Open)
 	CDockWidget* TopLevelDockWidgetAfter = DockContainer
 		? DockContainer->topLevelDockWidget() : nullptr;
 	CDockWidget::emitTopLevelEventForWidget(TopLevelDockWidgetAfter, true);
-	CFloatingDockContainer* FloatingContainer = DockContainer->floatingWidget();
+	CFloatingDockContainer* FloatingContainer = DockContainer
+		? DockContainer->floatingWidget() : nullptr;
 	if (FloatingContainer)
 	{
 		FloatingContainer->updateWindowTitle();
@@ -538,9 +606,9 @@ void CDockWidget::toggleViewInternal(bool Open)
 
 	if (!Open)
 	{
-		emit closed();
+		Q_EMIT closed();
 	}
-	emit viewToggled(Open);
+	Q_EMIT viewToggled(Open);
 }
 
 
@@ -580,11 +648,11 @@ bool CDockWidget::event(QEvent *e)
 	switch (e->type())
 	{
 	case QEvent::Hide:
-		emit visibilityChanged(false);
+		Q_EMIT visibilityChanged(false);
 		break;
 
 	case QEvent::Show:
-		emit visibilityChanged(geometry().right() >= 0 && geometry().bottom() >= 0);
+		Q_EMIT visibilityChanged(geometry().right() >= 0 && geometry().bottom() >= 0);
         break;
 
 	case QEvent::WindowTitleChange :
@@ -602,7 +670,7 @@ bool CDockWidget::event(QEvent *e)
 			{
 				d->DockArea->markTitleBarMenuOutdated();//update tabs menu
 			}
-			emit titleChanged(title);
+			Q_EMIT titleChanged(title);
 		}
 		break;
 
@@ -785,7 +853,7 @@ void CDockWidget::emitTopLevelChanged(bool Floating)
 	if (Floating != d->IsFloatingTopLevel)
 	{
 		d->IsFloatingTopLevel = Floating;
-		emit topLevelChanged(d->IsFloatingTopLevel);
+		Q_EMIT topLevelChanged(d->IsFloatingTopLevel);
 	}
 }
 
@@ -843,7 +911,7 @@ bool CDockWidget::closeDockWidgetInternal(bool ForceClose)
 {
 	if (!ForceClose)
 	{
-		emit closeRequested();
+		Q_EMIT closeRequested();
 	}
 
 	if (!ForceClose && features().testFlag(CDockWidget::CustomCloseHandling))
@@ -869,7 +937,7 @@ bool CDockWidget::closeDockWidgetInternal(bool ForceClose)
 			}
 		}
 		deleteDockWidget();
-		emit closed();
+		Q_EMIT closed();
     }
     else
     {

src/DockWidget.h

@@ -58,7 +58,7 @@ private:
     DockWidgetPrivate* d; ///< private data (pimpl)
     friend struct DockWidgetPrivate;
 
-private slots:
+private Q_SLOTS:
     /**
      * Adjusts the toolbar icon sizes according to the floating state
      */
@@ -147,15 +147,19 @@ public:
 
     enum DockWidgetFeature
     {
-        DockWidgetClosable = 0x01,///< dock widget has a close button
-        DockWidgetMovable = 0x02,///< dock widget is movable and can be moved to a new position in the current dock container
-        DockWidgetFloatable = 0x04,///< dock widget can be dragged into a floating window
-        DockWidgetDeleteOnClose = 0x08, ///< deletes the dock widget when it is closed
-        CustomCloseHandling = 0x10, ///< clicking the close button will not close the dock widget but emits the closeRequested() signal instead
-        DockWidgetFocusable = 0x20, ///< if this is enabled, a dock widget can get focus highlighting
+        DockWidgetClosable = 0x001,///< dock widget has a close button
+        DockWidgetMovable = 0x002,///< dock widget is movable and can be moved to a new position in the current dock container
+        DockWidgetFloatable = 0x004,///< dock widget can be dragged into a floating window
+        DockWidgetDeleteOnClose = 0x008, ///< deletes the dock widget when it is closed
+        CustomCloseHandling = 0x010, ///< clicking the close button will not close the dock widget but emits the closeRequested() signal instead
+        DockWidgetFocusable = 0x020, ///< if this is enabled, a dock widget can get focus highlighting
+        DockWidgetForceCloseWithArea = 0x040, ///< dock widget will be closed when the dock area hosting it is closed
+        NoTab = 0x080, ///< dock widget tab will never be shown if this flag is set
+        DeleteContentOnClose = 0x100, ///< deletes only the contained widget on close, keeping the dock widget intact and in place. Attempts to rebuild the contents widget on show if there is a widget factory set.
         DefaultDockWidgetFeatures = DockWidgetClosable | DockWidgetMovable | DockWidgetFloatable | DockWidgetFocusable,
         AllDockWidgetFeatures = DefaultDockWidgetFeatures | DockWidgetDeleteOnClose | CustomCloseHandling,
-        NoDockWidgetFeatures = 0x00
+        DockWidgetAlwaysCloseAndDelete = DockWidgetForceCloseWithArea | DockWidgetDeleteOnClose,
+        NoDockWidgetFeatures = 0x000
     };
     Q_DECLARE_FLAGS(DockWidgetFeatures, DockWidgetFeature)
 
@@ -251,7 +255,7 @@ public:
     /**
      * Sets the widget for the dock widget to widget.
      * The InsertMode defines how the widget is inserted into the dock widget.
-     * The content of a dock widget should be resizable do a very small size to
+     * The content of a dock widget should be resizable to a very small size to
      * prevent the dock widget from blocking the resizing. To ensure, that a
      * dock widget can be resized very well, it is better to insert the content+
      * widget into a scroll area or to provide a widget that is already a scroll
@@ -266,7 +270,19 @@ public:
      * provide the InsertMode ForceNoScrollArea
      */
     void setWidget(QWidget* widget, eInsertMode InsertMode = AutoScrollArea);
-
+	
+	/**
+	 * Only used when the feature flag DeleteContentOnClose is set.
+	 * Using the flag and setting a widget factory allows to free the resources
+	 * of the widget of your application while retaining the position the next
+	 * time you want to show your widget, unlike the flag DockWidgetDeleteOnClose
+	 * which deletes the dock widget itself. Since we keep the dock widget, all
+	 * regular features of ADS should work as normal, including saving and
+	 * restoring the state of the docking system and using perspectives.
+	 */
+	using FactoryFunc = std::function<QWidget*(QWidget*)>;
+	void setWidgetFactory(FactoryFunc createWidget, eInsertMode InsertMode = AutoScrollArea);
+	
     /**
      * Remove the widget from the dock and give ownership back to the caller
      */
@@ -481,7 +497,7 @@ public: // reimplements QFrame -----------------------------------------------
      */
     virtual bool event(QEvent *e) override;
 
-public slots:
+public Q_SLOTS:
     /**
      * This property controls whether the dock widget is open or closed.
      * The toogleViewAction triggers this slot
@@ -542,7 +558,7 @@ public slots:
     void showNormal();
 
 
-signals:
+Q_SIGNALS:
     /**
      * This signal is emitted if the dock widget is opened or closed
      */
@@ -584,7 +600,8 @@ signals:
      */
     void featuresChanged(ads::CDockWidget::DockWidgetFeatures features);
 }; // class DockWidget
-}
- // namespace ads
+} // namespace ads
+
+Q_DECLARE_OPERATORS_FOR_FLAGS(ads::CDockWidget::DockWidgetFeatures)
 //-----------------------------------------------------------------------------
 #endif // DockWidgetH

src/DockWidgetTab.cpp

@@ -50,8 +50,8 @@
 #include "DockOverlay.h"
 #include "DockManager.h"
 #include "IconProvider.h"
+#include "DockFocusController.h"
 
-#include <iostream>
 
 namespace ads
 {
@@ -77,6 +77,7 @@ struct DockWidgetTabPrivate
 	QAbstractButton* CloseButton = nullptr;
 	QSpacerItem* IconTextSpacer;
 	QPoint TabDragStartPosition;
+	QSize IconSize;
 
 	/**
 	 * Private data constructor
@@ -146,6 +147,19 @@ struct DockWidgetTabPrivate
 		CloseButton->setVisible(DockWidgetClosable && TabHasCloseButton);
 	}
 
+	/**
+	 * Update the size policy of the close button depending on the
+	 * RetainTabSizeWhenCloseButtonHidden feature
+	 */
+	void updateCloseButtonSizePolicy()
+	{
+		auto Features = DockWidget->features();
+		auto SizePolicy = CloseButton->sizePolicy();
+		SizePolicy.setRetainSizeWhenHidden(Features.testFlag(CDockWidget::DockWidgetClosable)
+			&& testConfigFlag(CDockManager::RetainTabSizeWhenCloseButtonHidden));
+		CloseButton->setSizePolicy(SizePolicy);
+	}
+
 	template <typename T>
 	IFloatingWidget* createFloatingWidget(T* Widget, bool OpaqueUndocking)
 	{
@@ -173,6 +187,35 @@ struct DockWidgetTabPrivate
 		DragStartMousePosition = _this->mapFromGlobal(GlobalPos);
 	}
 
+	/**
+	 * Update the icon in case the icon size changed
+	 */
+	void updateIcon()
+	{
+		if (!IconLabel || Icon.isNull())
+		{
+			return;
+		}
+
+		if (IconSize.isValid())
+		{
+			IconLabel->setPixmap(Icon.pixmap(IconSize));
+		}
+		else
+		{
+			IconLabel->setPixmap(Icon.pixmap(_this->style()->pixelMetric(QStyle::PM_SmallIconSize, nullptr, _this)));
+		}
+		IconLabel->setVisible(true);
+	}
+
+	/**
+	 * Convenience function for access to the dock manager dock focus controller
+	 */
+	CDockFocusController* focusController() const
+	{
+		return DockWidget->dockManager()->dockFocusController();
+	}
+
 };
 // struct DockWidgetTabPrivate
 
@@ -200,7 +243,8 @@ void DockWidgetTabPrivate::createLayout()
 	CloseButton->setObjectName("tabCloseButton");
 	internal::setButtonIcon(CloseButton, QStyle::SP_TitleBarCloseButton, TabCloseIcon);
     CloseButton->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
-    _this->onDockWidgetFeaturesChanged();
+    CloseButton->setFocusPolicy(Qt::NoFocus);
+    updateCloseButtonSizePolicy();
 	internal::setToolTip(CloseButton, QObject::tr("Close Tab"));
 	_this->connect(CloseButton, SIGNAL(clicked()), SIGNAL(closeRequested()));
 
@@ -225,7 +269,7 @@ void DockWidgetTabPrivate::createLayout()
 void DockWidgetTabPrivate::moveTab(QMouseEvent* ev)
 {
     ev->accept();
-    QPoint Distance = ev->globalPos() - GlobalDragStartMousePosition;
+    QPoint Distance = internal::globalPositionOf(ev) - GlobalDragStartMousePosition;
     Distance.setY(0);
     auto TargetPos = Distance + TabDragStartPosition;
     TargetPos.rx() = qMax(TargetPos.x(), 0);
@@ -297,10 +341,11 @@ CDockWidgetTab::CDockWidgetTab(CDockWidget* DockWidget, QWidget *parent) :
 	setAttribute(Qt::WA_NoMousePropagation, true);
 	d->DockWidget = DockWidget;
 	d->createLayout();
-	if (CDockManager::testConfigFlag(CDockManager::FocusHighlighting))
+	setFocusPolicy(Qt::NoFocus);
+	/*if (CDockManager::testConfigFlag(CDockManager::FocusHighlighting))
 	{
 		setFocusPolicy(Qt::ClickFocus);
-	}
+	}*/
 }
 
 //============================================================================
@@ -317,9 +362,13 @@ void CDockWidgetTab::mousePressEvent(QMouseEvent* ev)
 	if (ev->button() == Qt::LeftButton)
 	{
 		ev->accept();
-        d->saveDragStartMousePosition(ev->globalPos());
+        d->saveDragStartMousePosition(internal::globalPositionOf(ev));
         d->DragState = DraggingMousePressed;
-        emit clicked();
+        if (CDockManager::testConfigFlag(CDockManager::FocusHighlighting))
+        {
+        	d->focusController()->setDockWidgetTabFocused(this);
+        }
+        Q_EMIT clicked();
 		return;
 	}
 	Super::mousePressEvent(ev);
@@ -343,16 +392,30 @@ void CDockWidgetTab::mouseReleaseEvent(QMouseEvent* ev)
 			// End of tab moving, emit signal
 			if (d->DockArea)
 			{
-				emit moved(ev->globalPos());
+				ev->accept();
+                Q_EMIT moved(internal::globalPositionOf(ev));
 			}
 			break;
 
 		case DraggingFloatingWidget:
+			 ev->accept();
 			 d->FloatingWidget->finishDragging();
 			 break;
 
 		default:; // do nothing
 		}
+	} 
+	else if (ev->button() == Qt::MiddleButton)
+	{
+		if (CDockManager::testConfigFlag(CDockManager::MiddleMouseButtonClosesTab) && d->DockWidget->features().testFlag(CDockWidget::DockWidgetClosable))
+		{
+			// Only attempt to close if the mouse is still
+			// on top of the widget, to allow the user to cancel.
+			if (rect().contains(mapFromGlobal(QCursor::pos()))) {
+				ev->accept();
+				Q_EMIT closeRequested();
+			}
+		}
 	}
 
 	Super::mouseReleaseEvent(ev);
@@ -388,7 +451,7 @@ void CDockWidgetTab::mouseMoveEvent(QMouseEvent* ev)
     auto MappedPos = mapToParent(ev->pos());
     bool MouseOutsideBar = (MappedPos.x() < 0) || (MappedPos.x() > parentWidget()->rect().right());
     // Maybe a fixed drag distance is better here ?
-    int DragDistanceY = qAbs(d->GlobalDragStartMousePosition.y() - ev->globalPos().y());
+    int DragDistanceY = qAbs(d->GlobalDragStartMousePosition.y() - internal::globalPositionOf(ev).y());
     if (DragDistanceY >= CDockManager::startDragDistance() || MouseOutsideBar)
 	{
 		// If this is the last dock area in a dock container with only
@@ -420,7 +483,7 @@ void CDockWidgetTab::mouseMoveEvent(QMouseEvent* ev)
     	return;
 	}
     else if (d->DockArea->openDockWidgetsCount() > 1
-     && (ev->globalPos() - d->GlobalDragStartMousePosition).manhattanLength() >= QApplication::startDragDistance()) // Wait a few pixels before start moving
+     && (internal::globalPositionOf(ev) - d->GlobalDragStartMousePosition).manhattanLength() >= QApplication::startDragDistance()) // Wait a few pixels before start moving
 	{
     	// If we start dragging the tab, we save its inital position to
     	// restore it later
@@ -473,7 +536,7 @@ bool CDockWidgetTab::isActiveTab() const
 //============================================================================
 void CDockWidgetTab::setActiveTab(bool active)
 {
-	d->updateCloseButtonVisibility(active);
+    d->updateCloseButtonVisibility(active);
 
 	// Focus related stuff
 	if (CDockManager::testConfigFlag(CDockManager::FocusHighlighting) && !d->DockWidget->dockManager()->isRestoringState())
@@ -481,7 +544,8 @@ void CDockWidgetTab::setActiveTab(bool active)
 		bool UpdateFocusStyle = false;
 		if (active && !hasFocus())
 		{
-			setFocus(Qt::OtherFocusReason);
+			//setFocus(Qt::OtherFocusReason);
+			d->focusController()->setDockWidgetTabFocused(this);
 			UpdateFocusStyle = true;
 		}
 
@@ -504,7 +568,7 @@ void CDockWidgetTab::setActiveTab(bool active)
 	update();
 	updateGeometry();
 
-	emit activeTabChanged();
+	Q_EMIT activeTabChanged();
 }
 
 
@@ -557,11 +621,7 @@ void CDockWidgetTab::setIcon(const QIcon& Icon)
 	}
 
 	d->Icon = Icon;
-	if (d->IconLabel)
-	{
-		d->IconLabel->setPixmap(Icon.pixmap(style()->pixelMetric(QStyle::PM_SmallIconSize, nullptr, this)));
-		d->IconLabel->setVisible(true);
-	}
+	d->updateIcon();
 }
 
 
@@ -582,14 +642,18 @@ QString CDockWidgetTab::text() const
 //============================================================================
 void CDockWidgetTab::mouseDoubleClickEvent(QMouseEvent *event)
 {
-	// If this is the last dock area in a dock container it does not make
-	// sense to move it to a new floating widget and leave this one
-	// empty
-	if ((!d->DockArea->dockContainer()->isFloating() || d->DockArea->dockWidgetsCount() > 1)
-		&& d->DockWidget->features().testFlag(CDockWidget::DockWidgetFloatable))
+	if (event->button() == Qt::LeftButton) 
 	{
-		d->saveDragStartMousePosition(event->globalPos());
-		d->startFloating(DraggingInactive);
+		// If this is the last dock area in a dock container it does not make
+		// sense to move it to a new floating widget and leave this one
+		// empty
+		if ((!d->DockArea->dockContainer()->isFloating() || d->DockArea->dockWidgetsCount() > 1)
+			&& d->DockWidget->features().testFlag(CDockWidget::DockWidgetFloatable))
+		{
+			event->accept();
+			d->saveDragStartMousePosition(internal::globalPositionOf(event));
+			d->startFloating(DraggingInactive);
+		}
 	}
 
 	Super::mouseDoubleClickEvent(event);
@@ -599,7 +663,7 @@ void CDockWidgetTab::mouseDoubleClickEvent(QMouseEvent *event)
 //============================================================================
 void CDockWidgetTab::setVisible(bool visible)
 {
-	// Just here for debugging to insert debug output
+	visible &= !d->DockWidget->features().testFlag(CDockWidget::NoTab);
     Super::setVisible(visible);
 }
 
@@ -647,6 +711,9 @@ bool CDockWidgetTab::event(QEvent *e)
 	{
 		const auto text = toolTip();
 		d->TitleLabel->setToolTip(text);
+		if (d->IconLabel) {
+			d->IconLabel->setToolTip(text);
+		}
 	}
 #endif
 	return Super::event(e);
@@ -656,12 +723,8 @@ bool CDockWidgetTab::event(QEvent *e)
 //============================================================================
 void CDockWidgetTab::onDockWidgetFeaturesChanged()
 {
-	auto Features = d->DockWidget->features();
-	auto SizePolicy = d->CloseButton->sizePolicy();
-	SizePolicy.setRetainSizeWhenHidden(Features.testFlag(CDockWidget::DockWidgetClosable)
-		&& d->testConfigFlag(CDockManager::RetainTabSizeWhenCloseButtonHidden));
-	d->CloseButton->setSizePolicy(SizePolicy);
-	d->updateCloseButtonVisibility(isActiveTab());
+    d->updateCloseButtonSizePolicy();
+    d->updateCloseButtonVisibility(isActiveTab());
 }
 
 
@@ -679,6 +742,21 @@ void CDockWidgetTab::updateStyle()
 }
 
 
+//============================================================================
+QSize CDockWidgetTab::iconSize() const
+{
+	return d->IconSize;
+}
+
+
+//============================================================================
+void CDockWidgetTab::setIconSize(const QSize& Size)
+{
+	d->IconSize = Size;
+	d->updateIcon();
+}
+
+
 
 
 } // namespace ads

src/DockWidgetTab.h

@@ -31,6 +31,7 @@
 //                                   INCLUDES
 //============================================================================
 #include <QFrame>
+#include <QSize>
 
 #include "ads_globals.h"
 
@@ -50,6 +51,7 @@ class ADS_EXPORT CDockWidgetTab : public QFrame
 {
 	Q_OBJECT
 	Q_PROPERTY(bool activeTab READ isActiveTab WRITE setActiveTab NOTIFY activeTabChanged)
+	Q_PROPERTY(QSize iconSize READ iconSize WRITE setIconSize)
 
 private:
 	DockWidgetTabPrivate* d; ///< private data (pimpl)
@@ -58,7 +60,7 @@ private:
 	friend class CDockManager;
 	void onDockWidgetFeaturesChanged();
 
-private slots:
+private Q_SLOTS:
 	void detachDockWidget();
 
 protected:
@@ -159,10 +161,24 @@ public:
 	 */
 	void updateStyle();
 
-public slots:
+	/**
+	 * Returns the icon size.
+	 * If no explicit icon size has been set, the function returns an invalid
+	 * QSize
+	 */
+	QSize iconSize() const;
+
+	/**
+	 * Set an explicit icon size.
+	 * If no icon size has been set explicitely, than the tab sets the icon size
+	 * depending on the style
+	 */
+	void setIconSize(const QSize& Size);
+
+public Q_SLOTS:
 	virtual void setVisible(bool visible) override;
 
-signals:
+Q_SIGNALS:
 	void activeTabChanged();
 	void clicked();
 	void closeRequested();

src/ElidingLabel.cpp

@@ -74,7 +74,7 @@ void ElidingLabelPrivate::elideText(int Width)
     IsElided = str != Text;
     if(IsElided != WasElided)
     {
-        emit _this->elidedChanged(IsElided);
+        Q_EMIT _this->elidedChanged(IsElided);
     }
     _this->QLabel::setText(str);
 }
@@ -136,7 +136,7 @@ void CElidingLabel::mouseReleaseEvent(QMouseEvent* event)
 		return;
 	}
 
-	emit clicked();
+	Q_EMIT clicked();
 }
 
 
@@ -144,7 +144,7 @@ void CElidingLabel::mouseReleaseEvent(QMouseEvent* event)
 void CElidingLabel::mouseDoubleClickEvent( QMouseEvent *ev )
 {
 	Q_UNUSED(ev)
-	emit doubleClicked();
+	Q_EMIT doubleClicked();
 	Super::mouseDoubleClickEvent(ev);
 }
 
@@ -163,7 +163,12 @@ void CElidingLabel::resizeEvent(QResizeEvent *event)
 //============================================================================
 QSize CElidingLabel::minimumSizeHint() const
 {
-    if (pixmap() != nullptr || d->isModeElideNone())
+#if (QT_VERSION >= QT_VERSION_CHECK(5, 15, 0))
+    bool HasPixmap = !pixmap(Qt::ReturnByValue).isNull();
+#else
+    bool HasPixmap = (pixmap() != nullptr);
+#endif
+    if (HasPixmap || d->isModeElideNone())
     {
         return QLabel::minimumSizeHint();
     }
@@ -180,7 +185,12 @@ QSize CElidingLabel::minimumSizeHint() const
 //============================================================================
 QSize CElidingLabel::sizeHint() const
 {
-    if (pixmap() != nullptr || d->isModeElideNone())
+#if (QT_VERSION >= QT_VERSION_CHECK(5, 15, 0))
+    bool HasPixmap = !pixmap(Qt::ReturnByValue).isNull();
+#else
+    bool HasPixmap = (pixmap() != nullptr);
+#endif
+    if (HasPixmap || d->isModeElideNone())
     {
         return QLabel::sizeHint();
     }

src/ElidingLabel.h

@@ -58,8 +58,8 @@ protected:
 public:
     using Super = QLabel;
 
-	CElidingLabel(QWidget* parent = 0, Qt::WindowFlags f = 0);
-	CElidingLabel(const QString& text, QWidget* parent = 0, Qt::WindowFlags f = 0);
+    CElidingLabel(QWidget* parent = 0, Qt::WindowFlags f = Qt::WindowFlags ());
+    CElidingLabel(const QString& text, QWidget* parent = 0, Qt::WindowFlags f = Qt::WindowFlags ());
 	virtual ~CElidingLabel();
 
 	/**
@@ -84,7 +84,7 @@ public: // reimplements QLabel ----------------------------------------------
 	void setText(const QString &text);
 	QString text() const;
 
-signals:
+Q_SIGNALS:
 	/**
 	 * This signal is emitted if the user clicks on the label (i.e. pressed
 	 * down then released while the mouse cursor is inside the label)

src/FloatingDockContainer.cpp

@@ -373,6 +373,7 @@ struct FloatingDockContainerPrivate
 	CDockAreaWidget *SingleDockArea = nullptr;
 	QPoint DragStartPos;
 	bool Hiding = false;
+	bool AutoHideChildren = true;
 #ifdef Q_OS_LINUX
     QWidget* MouseEventHandler = nullptr;
     CFloatingWidgetTitleBar* TitleBar = nullptr;
@@ -609,7 +610,8 @@ CFloatingDockContainer::CFloatingDockContainer(CDockManager *DockManager) :
 #ifdef Q_OS_LINUX
 	QDockWidget::setWidget(d->DockContainer);
 	QDockWidget::setFloating(true);
-	QDockWidget::setFeatures(QDockWidget::AllDockWidgetFeatures);
+	QDockWidget::setFeatures(QDockWidget::DockWidgetClosable
+		| QDockWidget::DockWidgetMovable | QDockWidget::DockWidgetFloatable);
 
 	bool native_window = true;
 
@@ -733,8 +735,11 @@ void CFloatingDockContainer::changeEvent(QEvent *event)
 
 
 #ifdef Q_OS_WIN
-//============================================================================
+#if (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
 bool CFloatingDockContainer::nativeEvent(const QByteArray &eventType, void *message, long *result)
+#else
+bool CFloatingDockContainer::nativeEvent(const QByteArray &eventType, void *message, qintptr *result)
+#endif
 {
 	QWidget::nativeEvent(eventType, message, result);
 	MSG *msg = static_cast<MSG*>(message);
@@ -752,7 +757,7 @@ bool CFloatingDockContainer::nativeEvent(const QByteArray &eventType, void *mess
 		case WM_NCLBUTTONDOWN:
 			 if (msg->wParam == HTCAPTION && d->isState(DraggingInactive))
 			 {
-				ADS_PRINT("CFloatingDockContainer::nativeEvent WM_NCLBUTTONDOWN" << e->type());
+				ADS_PRINT("CFloatingDockContainer::nativeEvent WM_NCLBUTTONDOWN");
 				d->DragStartPos = pos();
 				d->setState(DraggingMousePressed);
 			 }
@@ -765,7 +770,7 @@ bool CFloatingDockContainer::nativeEvent(const QByteArray &eventType, void *mess
 		case WM_ENTERSIZEMOVE:
 			 if (d->isState(DraggingMousePressed))
 			 {
-				ADS_PRINT("CFloatingDockContainer::nativeEvent WM_ENTERSIZEMOVE" << e->type());
+				ADS_PRINT("CFloatingDockContainer::nativeEvent WM_ENTERSIZEMOVE");
 				d->setState(DraggingFloatingWidget);
 				d->updateDropOverlays(QCursor::pos());
 			 }
@@ -774,7 +779,7 @@ bool CFloatingDockContainer::nativeEvent(const QByteArray &eventType, void *mess
 		case WM_EXITSIZEMOVE:
 			 if (d->isState(DraggingFloatingWidget))
 			 {
-				ADS_PRINT("CFloatingDockContainer::nativeEvent WM_EXITSIZEMOVE" << e->type());
+				ADS_PRINT("CFloatingDockContainer::nativeEvent WM_EXITSIZEMOVE");
 				if (GetAsyncKeyState(VK_ESCAPE) & 0x8000)
 				{
 					d->handleEscapeKey();
@@ -837,15 +842,18 @@ void CFloatingDockContainer::hideEvent(QHideEvent *event)
         return;
     }
 
-    d->Hiding = true;
-	for (auto DockArea : d->DockContainer->openedDockAreas())
+	if ( d->AutoHideChildren )
 	{
-		for (auto DockWidget : DockArea->openedDockWidgets())
+		d->Hiding = true;
+		for ( auto DockArea : d->DockContainer->openedDockAreas() )
 		{
-			DockWidget->toggleView(false);
+			for ( auto DockWidget : DockArea->openedDockWidgets() )
+			{
+				DockWidget->toggleView( false );
+			}
 		}
+		d->Hiding = false;
 	}
-	d->Hiding = false;
 }
 
 
@@ -1031,6 +1039,18 @@ QList<CDockWidget*> CFloatingDockContainer::dockWidgets() const
 	return d->DockContainer->dockWidgets();
 }
 
+//============================================================================
+void CFloatingDockContainer::hideAndDeleteLater()
+{
+	// Widget has been redocked, so it must be hidden right way (see 
+	// https://github.com/githubuser0xFFFF/Qt-Advanced-Docking-System/issues/351)
+	// but AutoHideChildren must be set to false because "this" still contains
+	// dock widgets that shall not be toggled hidden.
+	d->AutoHideChildren = false;
+	hide();
+	deleteLater();
+}
+
 //============================================================================
 void CFloatingDockContainer::finishDragging()
 {

src/FloatingDockContainer.h

@@ -65,7 +65,7 @@ class CDockingStateReader;
  * This interface is used for opaque and non-opaque undocking. If opaque
  * undocking is used, the a real CFloatingDockContainer widget will be created
  */
-class IFloatingWidget
+class ADS_EXPORT IFloatingWidget
 {
 public:
     virtual ~IFloatingWidget() = default;
@@ -118,7 +118,7 @@ private:
 	friend class CDockAreaWidget;
     friend class CFloatingWidgetTitleBar;
 
-private slots:
+private Q_SLOTS:
 	void onDockAreasAddedOrRemoved();
 	void onDockAreaCurrentChanged(int Index);
 
@@ -194,7 +194,11 @@ protected: // reimplements QWidget
 	/**
 	 * Native event filter for handling WM_MOVING messages on Windows
 	 */
-	virtual bool nativeEvent(const QByteArray &eventType, void *message, long *result) override;
+#if (QT_VERSION < QT_VERSION_CHECK(6, 0, 0))
+    virtual bool nativeEvent(const QByteArray &eventType, void *message, long *result) override;
+#else
+    virtual bool nativeEvent(const QByteArray &eventType, void *message, qintptr *result) override;
+#endif
 #endif
 
 
@@ -254,6 +258,11 @@ public:
      */
     QList<CDockWidget*> dockWidgets() const;
 
+	/**
+	 * This function hides the floating bar instantely and delete it later.
+	 */
+	void hideAndDeleteLater();
+
 #ifdef Q_OS_LINUX
     /**
 	 * This is a function that responds to FloatingWidgetTitleBar::maximizeRequest()

src/FloatingDragPreview.cpp

@@ -60,7 +60,7 @@ struct FloatingDragPreviewPrivate
 	void cancelDragging()
 	{
 		Canceled = true;
-		emit _this->draggingCanceled();
+		Q_EMIT _this->draggingCanceled();
 		DockManager->containerOverlay()->hideOverlay();
 		DockManager->dockAreaOverlay()->hideOverlay();
 		_this->close();

src/FloatingDragPreview.h

@@ -32,7 +32,7 @@ private:
 	FloatingDragPreviewPrivate* d;
 	friend struct FloatingDragPreviewPrivate;
 
-private slots:
+private Q_SLOTS:
 	/**
 	 * Cancel non opaque undocking if application becomes inactive
 	 */
@@ -92,7 +92,7 @@ public: // implements IFloatingWidget -----------------------------------------
 	 */
 	virtual void finishDragging() override;
 
-signals:
+Q_SIGNALS:
 	/**
 	 * This signal is emitted, if dragging has been canceled by escape key
 	 * or by active application switching via task manager