I have an application that is using the Docking library through the Prism Integration open source library. In my application, the user has the ability to drag and drop items from one tabbed document window to another. During a drag operation, when the user drags over a tab from your docking library the tab automatically switches. This is great!
However, if I drop the item ontop the tab heading, the DragDropEffects.that is returned from my DragDrop.DoDragDrop call returns DragDropEffects.Move (which is an effect I allowed). The move operation was only supposed to be allowed when dragged to a specific control on my document window. When the source of the drag operation detects "Move" was completed successfully, it removes the data from the display on the original document window. If I were dragging it to my destination control, it would also be added to the new control. However, since your document window tab is accepting a completed "Move" effect, my data gets removed from the source control and disappears completely.
Basically, I like the DragOver behavior, but how can I stop it from telling my application it completed a drag operation? It should just return DragEffects.None I think?