Let me explain complete requirement.
I have telerik treeview on popup along with stackpanel.
Stackpanel contains list of objects of usercontrols (different class than popup child window) in which each usercontrol contains listbox.
i want drag drop from tree to listbox inside stackpanel.
Tree is having ParticipatingVisualRoots as child window class but stackpanel objects (user controls) have different ParticipatingVisualRoots .
Please make me correct if anything wrong