Programmatically adding document windows to a MDI

 
        StandardMdiHost MyMDIHost;
        DockSite MyDockSite;
 public override void BeginInit()
        {
            base.BeginInit();
            
            //Create the docking panel
            MyDockSite = CreateApplicationDockSite();

            //Create the WPF docking panel that will be the content of the WPF window.
            DockPanel MyDockPanel = new DockPanel();
            MyDockPanel.LastChildFill = true;

            //Add the docksite and the ribbon.
            //Note: The Actipro Ribbon has to be the last added.  Not sure why - their documentation does not
            //        state why...
            
            MyDockPanel.Children.Add(MyDockSite);
           
            this.ApplicationName = ApplicationInformation.ApplicationTitle;
            this.DocumentName = string.Empty;
            this.Content = MyDockPanel;
        }

        private DockSite CreateApplicationDockSite()
        {
            MyDockSite = new DockSite();
            MyDockSite.Name = "MyDockSite";
            MyDockSite.CanDocumentWindowsClose = false;

            SplitContainer MySplitContainer = new SplitContainer();

            //StandardMdiHost 
            MyMDIHost = new StandardMdiHost();
            MyMDIHost.Name = "MyMDIHost";

            MySplitContainer.Children.Add(MyMDIHost);

            MyDockSite.Content = MySplitContainer;

            return MyDockSite;
        }


        void ScreenButton_Click(object sender, ExecuteRoutedEventArgs e)
        {  
            try
            {

                DocumentWindow x = new DocumentWindow(MyDockSite);
                
                x.Activate();

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message.ToString());
            }
        }