[news.eclipse.platform.rcp] Overriding plugin.xml-supplied command handl

[pjcarreira@xxxxxxxxx (Paulo Carreira)]

Hi everyone,

I'm trying to override a command handler declared on plugin.xml from 
inside a view. Is there a way to do it?

In plugin.xml, I declare a global handler for the "paste" command that 
looks like this:
   <handler
        class="lxx.actions.PasteItemsToClipboardHandler"
        commandId="org.eclipse.ui.edit.paste">
     <activeWhen>
     <with variable="selection">                     
         <test property="lxx.propertytesters.canPasteItems"></test>      
        </with>
     </activeWhen>
  </handler>

(btw, this works and calls lxx.actions.PasteItemsToClipboardHandler 
whenever lxx.propertytesters.canPasteItems evaluates to True)

Now, in the view's CreatePartControl I have:

 public void createPartControl(Composite parent) {
      final IHandler myPasteHandler = new AbstractHandler() {
	 @Override
	 public Object execute(ExecutionEvent arg0) throws ExecutionException {
	   System.err.println("HELLO WORLD: MYPASTE");
	   return null;
        }
      };

      IHandlerService service = (IHandlerService)getSite().
            getService(IHandlerService.class);
      service.activateHandler("org.eclipse.ui.edit.paste", 
myPasteHandler, Expression.TRUE);
  
     // stuff...    
  }

I would expect that myPastHandler would always override the handler 
declared inside the plugin.xml (note that we're passing Expression.TRUE to 
the activateHanlder) but unfortunately the converse seems to happen: the 
global handler gets called preferentially and myPastHandler only gets 
called whenever lxx.propertytesters.canPasteItems returns False. Is this 
the way it should work?

Any ideas on how to override a command handler declared on the plugin.xml?

thanks in advance,
p.