Merge branch 'master' into focused_dockwidget

doc/user-guide.md

@@ -23,6 +23,8 @@
   - [`FloatingContainerHasWidgetTitle`](#floatingcontainerhaswidgettitle)
   - [`FloatingContainerHasWidgetIcon`](#floatingcontainerhaswidgeticon)
   - [`HideSingleCentralWidgetTitleBar`](#hidesinglecentralwidgettitlebar)
+- [Styling](#styling)
+  - [Disabling the Internal Style Sheet](#disabling-the-internal-style-sheet)
 
 ## Configuration Flags
 
@@ -297,3 +299,19 @@ still has a titlebar to drag it out of the main window.
 
 ![HideSingleCentralWidgetTitleBar false](cfg_flag_HideSingleCentralWidgetTitleBar_false.png)
 
+## 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
+icons are styleable this way.
+
+### Disabling the Internal Style Sheet
+
+The dock manager uses an internal stylesheet to style its components. That
+means, the style that you see in the demo application comes from the
+internal stylesheets that you will find in `src/stylesheets` folder. If you want
+to disable this internal stylesheet because your application uses its own,
+just call the function for settings the stylesheet with an empty string.
+
+```c++
+DockManager->setStyleSheet("");
+```

src/DockAreaTitleBar.h

@@ -86,7 +86,7 @@ protected:
 	/**
 	 * Show context menu
 	 */
-	virtual void contextMenuEvent(QContextMenuEvent *event);
+	virtual void contextMenuEvent(QContextMenuEvent *event) override;
 
 public slots:
 	/**

src/DockContainerWidget.cpp

@@ -415,9 +415,10 @@ void DockContainerWidgetPrivate::dropIntoContainer(CFloatingDockContainer* Float
 	}
 	else if (FloatingSplitter->orientation() == InsertParam.orientation())
 	{
+        int InsertIndex = InsertParam.append() ? Splitter->count() : 0;
 		while (FloatingSplitter->count())
 		{
-			insertWidgetIntoSplitter(Splitter, FloatingSplitter->widget(0), InsertParam.append());
+            Splitter->insertWidget(InsertIndex++, FloatingSplitter->widget(0));
 		}
 	}
 	else
@@ -575,6 +576,11 @@ void DockContainerWidgetPrivate::moveIntoCenterOfSection(QWidget* Widget, CDockA
 	if (DroppedDockWidget)
 	{
 		CDockAreaWidget* OldDockArea = DroppedDockWidget->dockAreaWidget();
+		if (OldDockArea == TargetArea)
+		{
+			return;
+		}
+
 		if (OldDockArea)
 		{
 			OldDockArea->removeDockWidget(DroppedDockWidget);