JXLayer implementation

Want to use JXLayer to block my GUI when some worker thread is running. I guess it was that simple:

JPanel panel = getMyPanel();       
LockableUI lockableUI = new LockableUI();        
JXLayer l = new JXLayer(panel, lockableUI);        
lockableUI.setLocked(false);
add(l);

      

        
        
        
      

    

the first error is that the getMyPanel () function is undefined by default. I added jxlayer3-0.jar

I need a panel that I want to lock ... so if I switch the first line with:

JPanel p =(JPanel) getContentPane();

      

        
        
        
      

    

but then I get a warning that I am adding the parent container to it myself. Can't find any documentation for JXLayer