Get selected items from the locals / autos / watch window

Hi, I'm trying to write an extension that lets you right click an item in the watch window to create a conditional or data breakpoint from it.  To do this, I need to get the thing that was clicked on, or at least the current selection.  I've spent a while reading docs and trying out ideas, but so far nothing has worked.  Is there any way to do it?  Thanks for your help!