static void OnMostRecentlyUsedTypesPropertyChanged(DependencyObject sender, DependencyPropertyChangedEventArgs args)
        {
            TypePresenter ctrl = (TypePresenter)sender;

            ((ObservableCollection <Type>)args.NewValue).CollectionChanged += ctrl.OnMostRecentlyUsedTypesChanged;
            ((ObservableCollection <Type>)args.OldValue).CollectionChanged -= ctrl.OnMostRecentlyUsedTypesChanged;

            ctrl.OnItemsChanged();
        }
        static void OnAllowNullChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
        {
            TypePresenter ctrl = (TypePresenter)sender;

            ctrl.OnItemsChanged();
        }
        static void OnContextChanged(DependencyObject sender, DependencyPropertyChangedEventArgs args)
        {
            TypePresenter ctrl = (TypePresenter)sender;

            ctrl.OnItemsChanged();
        }