protected override void UnloadCore()
 {
     contentGroup = null;
     RibbonEntries.Clear();
     StatusBarItems.Clear();
     GisEditor.DockWindowManager.DocumentWindows.CollectionChanged -= DocumentWindows_CollectionChanged;
 }
        public ContentUIPlugin()
        {
            Description     = GisEditor.LanguageManager.GetStringResource("ContentUIPluginDescription");
            SmallIcon       = new BitmapImage(new Uri("/GisEditorPluginCore;component/Images/NewContent.png", UriKind.RelativeOrAbsolute));
            LargeIcon       = new BitmapImage(new Uri("/GisEditorPluginCore;component/Images/NewContent.png", UriKind.RelativeOrAbsolute));
            Index           = UIPluginOrder.ContentPlugin;
            initializedMaps = new Collection <GisEditorWpfMap>();

            //IndexAdapterManager.Instance.GetPlugins();
            //ShapeAdapterManager.Instance.GetPlugins();
            InteractiveOverlayPluginManager.Instance.GetPlugins();

            contentGroup = new ContentRibbonGroup();
            contentEntry = new RibbonEntry(contentGroup, RibbonTabOrder.Home, "HomeRibbonTabHeader");
        }