Added initial support for transparent undocking

src/FloatingOverlay.cpp

@@ -0,0 +1,277 @@
+//============================================================================
+/// \file   FloatingOverlay.cpp
+/// \author Uwe Kindler
+/// \date   26.11.2019
+/// \brief  Implementation of CFloatingOverlay
+//============================================================================
+
+//============================================================================
+//                                   INCLUDES
+//============================================================================
+#include "FloatingOverlay.h"
+
+#include <iostream>
+
+#include <QEvent>
+#include <QApplication>
+#include <QPainter>
+
+#include "DockWidget.h"
+#include "DockAreaWidget.h"
+#include "DockManager.h"
+#include "DockContainerWidget.h"
+#include "DockOverlay.h"
+
+namespace ads
+{
+
+/**
+ * Private data class (pimpl)
+ */
+struct FloatingOverlayPrivate
+{
+	CFloatingOverlay *_this;
+	QWidget* Content;
+	QPoint DragStartMousePosition;
+	CDockManager* DockManager;
+	CDockContainerWidget *DropContainer = nullptr;
+	qreal WindowOpacity;
+	bool Hidden = false;
+
+
+	/**
+	 * Private data constructor
+	 */
+	FloatingOverlayPrivate(CFloatingOverlay *_public);
+	void updateDropOverlays(const QPoint &GlobalPos);
+
+	void setHidden(bool Value)
+	{
+		Hidden = Value;
+		_this->update();
+	}
+};
+// struct LedArrayPanelPrivate
+
+
+//============================================================================
+void FloatingOverlayPrivate::updateDropOverlays(const QPoint &GlobalPos)
+{
+	if (!_this->isVisible() || !DockManager)
+	{
+		return;
+	}
+
+	auto Containers = DockManager->dockContainers();
+	CDockContainerWidget *TopContainer = nullptr;
+	for (auto ContainerWidget : Containers)
+	{
+		if (!ContainerWidget->isVisible())
+		{
+			continue;
+		}
+
+		/*if (DockContainer == ContainerWidget)
+		{
+			continue;
+		}*/
+
+		QPoint MappedPos = ContainerWidget->mapFromGlobal(GlobalPos);
+		if (ContainerWidget->rect().contains(MappedPos))
+		{
+			if (!TopContainer || ContainerWidget->isInFrontOf(TopContainer))
+			{
+				TopContainer = ContainerWidget;
+			}
+		}
+	}
+
+	DropContainer = TopContainer;
+	auto ContainerOverlay = DockManager->containerOverlay();
+	auto DockAreaOverlay = DockManager->dockAreaOverlay();
+
+	if (!TopContainer)
+	{
+		ContainerOverlay->hideOverlay();
+		DockAreaOverlay->hideOverlay();
+		setHidden(false);
+		return;
+	}
+
+	int VisibleDockAreas = TopContainer->visibleDockAreaCount();
+	ContainerOverlay->setAllowedAreas(
+	    VisibleDockAreas > 1 ? OuterDockAreas : AllDockAreas);
+	DockWidgetArea ContainerArea = ContainerOverlay->showOverlay(TopContainer);
+	ContainerOverlay->enableDropPreview(ContainerArea != InvalidDockWidgetArea);
+	auto DockArea = TopContainer->dockAreaAt(GlobalPos);
+	if (DockArea && DockArea->isVisible() && VisibleDockAreas > 0)
+	{
+		DockAreaOverlay->enableDropPreview(true);
+		DockAreaOverlay->setAllowedAreas(
+		    (VisibleDockAreas == 1) ? NoDockWidgetArea : AllDockAreas);
+		DockWidgetArea Area = DockAreaOverlay->showOverlay(DockArea);
+
+		// A CenterDockWidgetArea for the dockAreaOverlay() indicates that
+		// the mouse is in the title bar. If the ContainerArea is valid
+		// then we ignore the dock area of the dockAreaOverlay() and disable
+		// the drop preview
+		if ((Area == CenterDockWidgetArea)
+		    && (ContainerArea != InvalidDockWidgetArea))
+		{
+			DockAreaOverlay->enableDropPreview(false);
+			ContainerOverlay->enableDropPreview(true);
+		}
+		else
+		{
+			ContainerOverlay->enableDropPreview(InvalidDockWidgetArea == Area);
+		}
+	}
+	else
+	{
+		DockAreaOverlay->hideOverlay();
+	}
+
+	auto DockDropArea = DockAreaOverlay->dropAreaUnderCursor();
+	auto ContainerDropArea = ContainerOverlay->dropAreaUnderCursor();
+	setHidden(DockDropArea != InvalidDockWidgetArea || ContainerDropArea != InvalidDockWidgetArea);
+}
+
+
+//============================================================================
+FloatingOverlayPrivate::FloatingOverlayPrivate(CFloatingOverlay *_public) :
+	_this(_public)
+{
+
+}
+
+//============================================================================
+CFloatingOverlay::CFloatingOverlay(QWidget* Content, QWidget* parent) :
+	QFrame(parent),
+	d(new FloatingOverlayPrivate(this))
+{
+	d->Content = Content;
+	setAttribute(Qt::WA_DeleteOnClose);
+
+	setWindowFlags(Qt::Tool | Qt::FramelessWindowHint);
+	setWindowOpacity(1);
+	setWindowTitle("FloatingOverlay");
+	setAttribute(Qt::WA_NoSystemBackground);
+	setAttribute(Qt::WA_TranslucentBackground);
+	// We install an event filter to detect mouse release events because we
+	// do not receive mouse release event if the floating widget is behind
+	// the drop overlay cross
+	qApp->installEventFilter(this);
+}
+
+
+//============================================================================
+CFloatingOverlay::CFloatingOverlay(CDockWidget* Content, QWidget* parent)
+	: CFloatingOverlay((QWidget*)Content, Content->dockManager())
+{
+	d->DockManager = Content->dockManager();
+}
+
+
+//============================================================================
+CFloatingOverlay::CFloatingOverlay(CDockAreaWidget* Content, QWidget* parent)
+	: CFloatingOverlay((QWidget*)Content, Content->dockManager())
+{
+	d->DockManager = Content->dockManager();
+}
+
+
+//============================================================================
+CFloatingOverlay::~CFloatingOverlay()
+{
+	delete d;
+}
+
+
+//============================================================================
+void CFloatingOverlay::moveFloating()
+{
+	int BorderSize = (frameSize().width() - size().width()) / 2;
+	const QPoint moveToPos = QCursor::pos() - d->DragStartMousePosition
+	    - QPoint(BorderSize, 0);
+	move(moveToPos);
+}
+
+
+//============================================================================
+void CFloatingOverlay::startFloating(const QPoint &DragStartMousePos,
+    const QSize &Size, eDragState DragState, QWidget *MouseEventHandler)
+{
+	Q_UNUSED(MouseEventHandler)
+	Q_UNUSED(DragState)
+	resize(Size);
+	d->DragStartMousePosition = DragStartMousePos;
+	moveFloating();
+	show();
+
+}
+
+
+//============================================================================
+void CFloatingOverlay::moveEvent(QMoveEvent *event)
+{
+	std::cout << "CFloatingOverlay::moveEvent" << std::endl;
+	QWidget::moveEvent(event);
+	d->updateDropOverlays(QCursor::pos());
+}
+
+
+//============================================================================
+bool CFloatingOverlay::eventFilter(QObject *watched, QEvent *event)
+{
+	Q_UNUSED(watched);
+	if (event->type() == QEvent::MouseButtonRelease)
+	{
+		ADS_PRINT("FloatingWidget::eventFilter QEvent::MouseButtonRelease");
+		std::cout << "CFloatingOverlay::eventFilter QEvent::MouseButtonRelease" << std::endl;
+
+		if (d->DropContainer)
+		{
+			d->DropContainer->dropWidget(d->Content, QCursor::pos());
+			d->DropContainer = nullptr;
+		}
+
+		this->close();
+		d->DockManager->containerOverlay()->hideOverlay();
+		d->DockManager->dockAreaOverlay()->hideOverlay();
+	}
+
+	return false;
+}
+
+
+//============================================================================
+void CFloatingOverlay::paintEvent(QPaintEvent* event)
+{
+	Q_UNUSED(event);
+
+	if (d->Hidden)
+	{
+		return;
+	}
+
+	QRect r = rect();
+	QPainter painter(this);
+    QColor Color = palette().color(QPalette::Active, QPalette::Highlight);
+    QPen Pen = painter.pen();
+    Pen.setColor(Color.darker(120));
+    Pen.setStyle(Qt::SolidLine);
+    Pen.setWidth(1);
+    Pen.setCosmetic(true);
+    painter.setPen(Pen);
+    Color = Color.lighter(130);
+    Color.setAlpha(64);
+    painter.setBrush(Color);
+	painter.drawRect(r.adjusted(0, 0, -1, -1));
+}
+
+
+
+} // namespace ads
+
+//---------------------------------------------------------------------------
+// EOF FloatingOverlay.cpp