Added initial support for transparent undocking

demo/MainWindow.cpp

@@ -50,6 +50,7 @@
 #include <QWidgetAction>
 #include <QComboBox>
 #include <QInputDialog>
+#include <QRubberBand>
 
 #include <QMap>
 #include <QElapsedTimer>
@@ -321,7 +322,7 @@ CMainWindow::CMainWindow(QWidget *parent) :
 
 	// uncomment the following line if you wand a fixed tab width that does
 	// not change if the visibility of the close button changes
-	// CDockManager::setConfigFlag(CDockManager::RetainTabSizeWhenCloseButtonHidden, true);
+	CDockManager::setConfigFlag(CDockManager::OpaqueUndocking, false);
 
 	// Now create the dock manager and its content
 	d->DockManager = new CDockManager(this);