protected override void Setup() { SetEditingExtender(TargetElement, this); UpdateEditMode(); TargetElement.AddHandler(FrameworkElement.PreviewKeyDownEvent, new RoutedEventHandler(TargetElement_PreviewKeyDown), true); //TargetElement.PreviewKeyDown += TargetElement_PreviewKeyDown; TargetElement.PreviewMouseDown += TargetElement_PreviewMouseDown; }