The use of ContentPropertyAttribute in TransitionControl

[Sandi Markon]

The thing is, i want to be able to add custom user controls to the TransitionControl. Something like...

       

<local:CardControl>
    <Button Content="Hello" />
    <Button Content="Hello" />
</local:CardControl>

...and to be able to implement custom transition logic inside the inherited class.

Now, the class CardControl inherits from RadTransitionControl, like shown below:

     [ContentProperty("Items")]

    [ContentWrapper(typeof(Collection<UIElement>))]

    public class CardControl : RadTransitionControl

    {

        public static readonly DependencyProperty ItemsProperty =

            DependencyProperty.Register("Items", typeof(Collection<UIElement>),
                 typeof(CardControl), new FrameworkPropertyMetadata(new Collection<UIElement>(),
FrameworkPropertyMetadataOptions.AffectsRender
, OnItemsChanged));

                               


 

 public Collection<UIElement> Items

 {

    get { return (Collection<UIElement>)GetValue(ItemsProperty); }

    set

        {

          SetValue(ItemsProperty, value);

        }

 }

       

        public CardControl()

        {

            

        }

 

        private static void OnItemsChanged(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs eventArgs)

        {

            (dependencyObject as CardControl).Content = (eventArgs.NewValue as Collection<UIElement>)[0];

        }

    }

As you can see, I've added the ContentPropertyAttribute, which in turn, should allow the user to add items in XAML, and store them in the Items property. It works, if i use a single item, but it shows no reaction, when i try to use the collection of UIElements.

Any ideas on how to make it work?
Thanks,

[Sandi Markon]

I've figured it out. The OnItemsChanged callback didn't fire, when the number of items changed in the collection, so I used the CollectionChanged event of the ObservableCollection<UIElement>, and it went smoothly :)