EntityCollection and TreeListView

[Benjamin]

Hello,

I'am using Q1 2013 and Entity Framework.
Th UI is not refreshed when I bound the child source to EntityCollection.
Does the TileListView support the AssociationChanged event of EntityCollection ?

Thank you

[Rossen Hristov]

Hi,

I am afraid that RadTreeListView can only listen for the standard .NET events such as INotifyCollectionChanged. Unfortunately, we can not tightly couple it with EntityCollection to listen specifically for this AssociationChanged event, which I even could not find on the EntityCollection class.

Maybe this StackOverflow discussions can give you some ideas.

Regards,
Rossen Hristov
the Telerik team

[Benjamin]

Hi,

Thanks for your help.
The AssociationChanged event belong to the base class of EntityCollection :  RelationEnd class.
I add a converter in order to create the ObservableCollections and make the wrap :

public class RelatedEndToObservableCollectionConverter : IValueConverter
{
    #region Fields

    private Dictionary<RelatedEnd, ObservableCollection<object>> _Dictionary;

    #endregion

    #region Constructors

    public RelatedEndToObservableCollectionConverter()
    {
        _Dictionary = new Dictionary<RelatedEnd, ObservableCollection<object>>();
    }

    #endregion

    #region Methods

    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        if (!_Dictionary.Keys.Contains(value))
        {

            RelatedEnd relatedEnd = (RelatedEnd)value;
            ObservableCollection<object> wraperCollection = new ObservableCollection<object>();
            this._Dictionary.Add(relatedEnd, wraperCollection);

            relatedEnd.AssociationChanged += relatedEnd_AssociationChanged;

            foreach (var item in relatedEnd)
            {
                wraperCollection.Add(item);
            }


        }
        return _Dictionary[(RelatedEnd)value];
    }

    public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        throw new NotImplementedException();
    }

    void relatedEnd_AssociationChanged(object sender, System.ComponentModel.CollectionChangeEventArgs e)
    {
        switch (e.Action)
        {
            case System.ComponentModel.CollectionChangeAction.Add:
                _Dictionary[(RelatedEnd)sender].Add(e.Element);
                break;
            case System.ComponentModel.CollectionChangeAction.Refresh:
                _Dictionary[(RelatedEnd)sender].Clear();
                foreach (var item in (RelatedEnd)sender)
                {
                    _Dictionary[(RelatedEnd)sender].Add(item);
                }
                break;
            case System.ComponentModel.CollectionChangeAction.Remove:
                _Dictionary[(RelatedEnd)sender].Remove(e.Element);
                break;
            default:
                break;
        }
    }

    #endregion
}

And i use it like that :

        <telerik:RadTreeListView ItemsSource="{Binding Invoice.Chapters}" SelectedItem="{Binding SelectedItem}">
          <telerik:RadTreeListView.ChildTableDefinitions>
            <telerik:TreeListViewTableDefinition>
              <telerik:TreeListViewTableDefinition.ItemsSource>
                <Binding Path="Chapters">
                  <Binding.Converter>
                    <converters:RelatedEndToObservableCollectionConverter/>
                  </Binding.Converter>
                </Binding>
              </telerik:TreeListViewTableDefinition.ItemsSource>
            </telerik:TreeListViewTableDefinition>
          </telerik:RadTreeListView.ChildTableDefinitions>
...

I have a graphic bug in the TreeListView (please see the attached image), there are white spaces in the control.
Does I made something wrong or does it's a bug from the TreeListView ?

Thank you for your help

[Benjamin]

Hey,

My bad, I just found the solution, I had to populate the ObservableCollection before subscribe to the AssociationChanged event.

Thank tou !