//TreeView
 public static Tree treeView(this UIItemContainer container)
 {
     if (container.notNull())
     {
         return(container.Get <Tree>());
     }
     return(null);
 }
 //Link
 public static Hyperlink link(this UIItemContainer container, string text)
 {
     if (container.notNull())
     {
         return(container.get <Hyperlink>(text));
     }
     return(null);
 }
 public static MenuBar menu(this UIItemContainer container)
 {
     if (container.notNull())
     {
         return(container.MenuBar);
     }
     return(null);
 }
 //Button
 public static Button button(this UIItemContainer container, string text)
 {
     if (container.notNull())
     {
         return(container.get <Button>(text));
     }
     return(null);
 }
 public static List <T> items <T>(this UIItemContainer container)
     where T : IUIItem
 {
     if (container.notNull())
     {
         return((from item in container.Items
                 where item is T
                 select(T) item).toList());
     }
     return(new List <T>());
 }