Drag & Drop duplicat items

[Kacem]

Hi,
I have a Treeveiw bound to an ObservableCollection TheClassifications :

<telerik:RadTreeView Grid.Column="2"
            SelectionMode="Multiple" IsLineEnabled="True" IsExpandOnDblClickEnabled="True" IsExpandOnSingleClickEnabled="True" IsSingleExpandPath="False" IsDragDropEnabled="True"
            IsRootLinesEnabled="True" Margin="10" x:Name="RadTreeView1" IsTriStateMode="True"
            ItemsSource="{Binding TheClassifications, Mode=TwoWay}"
            ItemTemplate="{StaticResource myTelerikHierarchicalTemplate}" />

ObservableCollection<ClassificationItem> TheClassifications_;
        public ObservableCollection<ClassificationItem> TheClassifications
        {
            get { return TheClassifications_; }
            set { SetObjValue(TheClassifications_, value, x => TheClassifications_ = x, () => TheClassifications); }
        }

I have 2 problems :
1- I can drop elements only on the root node
2- The droped elements are duplicated
I'll attach a screenshot to show you those problems...

How can I fix it ?
Thanks
Kacem

[Kacem]

I think I know what's the problem.
I'm using Ria Services SP1 and my collection is an EntityCollection, so I can't change it :(

Is there any issue ?

[Fabien]

Hi, I think you have to enable the Drag&Drop on each sub element (using a Style), and not only on the TreeView

[Kacem]

@Fabien : No I don't think so, on demos they enable drag&drop one time ...

Edit : 
This post may help others : http://www.telerik.com/community/forums/silverlight/treeview/can-not-drag-drop-the-radtreeview-nodes.aspx#1019981

[Petar Mladenov]

Hello Kacem,

 When using Drag'n'Drop it's important that the ItemsSource colelction of the TreeView is ObservableCollections and the destination item's child collection is already initialized. When working with services that return IEnumerable, you can create a wrapper classes that use ObservableCollections. In this blog post you can check out how this could be achieved. 

Regards,
Petar Mladenov
the Telerik team

[Kacem]

I prefer bind my Treeview directly to ria services collection...
Is there any way to manage Add/Remove operations myself ?
With RadTreeView I can't drop any elements on my nodes, so the idea is to allow drop and manage the operations myself ...

Thanks
Kacem

[Petar Mladenov]

Hi Kacem,

 The way to manage the CRUD operations on your own is to handle the RadDragAndDropManager's events in the RadTreeView. You can find more info on how to work with these events in this documentation article.
Please let us know if you need more info on this.

Regards,
Petar Mladenov
the Telerik team