Changed demos to delete the dock manager when the main window is closes to ensure that all floating widgets als "closed" (destroyed)

examples/sidebar/MainWindow.cpp

@@ -51,3 +51,13 @@ MainWindow::~MainWindow()
 {
     delete ui;
 }
+
+
+void MainWindow::closeEvent(QCloseEvent *event)
+{
+    QMainWindow::closeEvent(event);
+    if (m_DockManager)
+    {
+        m_DockManager->deleteLater();
+    }
+}

examples/sidebar/MainWindow.h

@@ -22,6 +22,9 @@ public:
     explicit MainWindow(QWidget *parent = 0);
     ~MainWindow();
 
+protected:
+    virtual void closeEvent(QCloseEvent *event) override;
+
 private:
     Ui::MainWindow *ui;
     ads::CDockManager* m_DockManager;