[Solved] Upgrade Drag & Drop issue

[Alessio]

Hi everyone,
i've just upgrade my solution with the lastest version of controls.
When i try to drag an item from a tree view to a gridview, just like the example you provide in demo, i get this error:
"Riga: 62
Errore: Unhandled Error in Silverlight Application
Code: 4004   
Category: ManagedRuntimeError      
Message: System.NullReferenceException: Riferimento a un oggetto non impostato su un'istanza di oggetto.
   su Telerik.Windows.Controls.DragDrop.RadDragAndDropManager.SetAllowDrag(DependencyObject obj, Boolean value)
   su Telerik.Windows.Controls.GridView.DragDropController.OnHeaderCellLoaded(Object sender, CellEventArgs e)".

Unfortunately my code is very complex and i can't provide here an example...
However the problem seems to be in the custom column definition, infact by set autogeneratecolumns to true and removing my custom columns the project works fine.
Any ideas?

[Tsvyatko]

Hello Alessio,

Is it possible to share some more information - scaledown project, xaml of the columns defined, since we are unable reproduce such problem from our side.

Regards,
Tsvyatko
the Telerik team