[news.eclipse.modeling.gmf] Opening a new diagram on double click diagra

["Johann" <td_jbrun@xxxxxxxxx>]

I would like to double click on a diagram element to cause another diagram 
to pop up with the clicked element as the diagram root element.

So for example, I have the Root object as my model root, then Diagram 
objects that are children of this Root object. I want one GMF diagram to 
display the direct children of Root, the various Diagram objects, as nodes. 
Then when the user double clicks a Diagram node, another GMF diagram will 
pop up that shows the contents of the double-clicked Diagram object.

So far, I've created 2 GMF diagrams at the 2 levels of the model. I then 
defined and registered a subclass of OpenDiagramEditPolicy for the 
DiagramEditPart at the Root level diagram.  But I can't figure out what to 
put in the getOpenCommand method to make it actually work -- right now it 
doesn't do anything on a double click.

Am I on the right track to get the 2 levels of diagrams that I want? How can 
I get this double click functionality to work?

Thanks,

Johann