Some changes for dockwidget tab close button, some refactorings to make insertion of widgets into dock widget easier, added createDefaultToolBar function for creation of toolbar and removed layout flags from CDockWidget

src/DockWidgetTab.cpp

@@ -38,6 +38,8 @@
 #include <QApplication>
 #include <QSplitter>
 #include <QDebug>
+#include <QToolButton>
+#include <QPushButton>
 
 #include "ads_globals.h"
 #include "DockWidget.h"
@@ -46,6 +48,8 @@
 #include "DockOverlay.h"
 #include "DockManager.h"
 
+#include <iostream>
+
 namespace ads
 {
 /**
@@ -60,6 +64,7 @@ enum eDragState
 };
 
 using tTabLabel = CElidingLabel;
+using tCloseButton = QPushButton;
 
 /**
  * Private data class of CDockWidgetTab class (pimpl)
@@ -76,6 +81,8 @@ struct DockWidgetTabPrivate
 	eDragState DragState = DraggingInactive;
 	CFloatingDockContainer* FloatingWidget = nullptr;
 	QIcon Icon;
+	tCloseButton* CloseButton = nullptr;
+	QSpacerItem* IconTextSpacer;
 
 	/**
 	 * Private data constructor
@@ -131,22 +138,39 @@ DockWidgetTabPrivate::DockWidgetTabPrivate(CDockWidgetTab* _public) :
 //============================================================================
 void DockWidgetTabPrivate::createLayout()
 {
-	QBoxLayout* l = new QBoxLayout(QBoxLayout::LeftToRight);
-	l->setContentsMargins(0, 0, 0, 0);
-	_this->setLayout(l);
-
-	IconLabel = new QLabel();
-	IconLabel->setAlignment(Qt::AlignVCenter);
-	IconLabel->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Preferred);
-	l->addWidget(IconLabel, Qt::AlignVCenter);
-
 	TitleLabel = new tTabLabel();
 	TitleLabel->setElideMode(Qt::ElideRight);
 	TitleLabel->setText(DockWidget->windowTitle());
 	TitleLabel->setObjectName("dockWidgetTabLabel");
-	l->addWidget(TitleLabel, 1);
+	TitleLabel->setAlignment(Qt::AlignCenter);
+
+	CloseButton = new tCloseButton();
+	CloseButton->setObjectName("tabCloseButton");
+	// The standard icons do does not look good on high DPI screens
+	QIcon CloseIcon =  _this->style()->standardIcon(QStyle::SP_TitleBarCloseButton);
+	QPixmap normalPixmap = _this->style()->standardPixmap(QStyle::SP_TitleBarCloseButton, 0, CloseButton);
+	QPixmap disabledPixmap = internal::createTransparentPixmap(normalPixmap, 0.25);
+	CloseIcon.addPixmap(disabledPixmap, QIcon::Disabled);
+	CloseButton->setIcon(CloseIcon);
+	CloseButton->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed);
+	CloseButton->setVisible(false);
+	CloseButton->setToolTip(QObject::tr("Close Tab"));
+	_this->connect(CloseButton, SIGNAL(clicked()), SIGNAL(closeButtonClicked()));
+
+	QFontMetrics fm(TitleLabel->font());
+	int Spacing = qRound(fm.height() / 4.0);
+
+	// Fill the layout
+	QBoxLayout* Layout = new QBoxLayout(QBoxLayout::LeftToRight);
+	Layout->setContentsMargins(2 * Spacing,0,0,0);
+	Layout->setSpacing(0);
+	_this->setLayout(Layout);
+	Layout->addWidget(TitleLabel, 1);
+	Layout->addSpacing(Spacing);
+	Layout->addWidget(CloseButton);
+	Layout->addSpacing(qRound(Spacing * 4.0 / 3.0));
+	Layout->setAlignment(Qt::AlignCenter);
 
-	IconLabel->setVisible(false);
 	TitleLabel->setVisible(true);
 }
 
@@ -323,6 +347,7 @@ bool CDockWidgetTab::isActiveTab() const
 //============================================================================
 void CDockWidgetTab::setActiveTab(bool active)
 {
+	d->CloseButton->setVisible(active && d->DockWidget->features().testFlag(CDockWidget::DockWidgetClosable));
 	if (d->IsActiveTab == active)
 	{
 		return;
@@ -363,8 +388,15 @@ CDockAreaWidget* CDockWidgetTab::dockAreaWidget() const
 //============================================================================
 void CDockWidgetTab::setIcon(const QIcon& Icon)
 {
+	QBoxLayout* Layout = qobject_cast<QBoxLayout*>(layout());
 	d->Icon = Icon;
+	d->IconLabel = new QLabel();
+	d->IconLabel->setAlignment(Qt::AlignVCenter);
+	d->IconLabel->setSizePolicy(QSizePolicy::Fixed, QSizePolicy::Preferred);
+	d->IconLabel->setToolTip(d->TitleLabel->toolTip());
 	d->IconLabel->setPixmap(Icon.pixmap(this->windowHandle(), QSize(16, 16)));
+	Layout->insertWidget(0, d->IconLabel, Qt::AlignVCenter);
+	Layout->insertSpacing(1, qRound(1.5 * Layout->contentsMargins().left() / 2.0));
 	d->IconLabel->setVisible(true);
 }
 
@@ -405,6 +437,7 @@ void CDockWidgetTab::setVisible(bool visible)
 	Super::setVisible(visible);
 }
 
+
 } // namespace ads
 
 //---------------------------------------------------------------------------