Swing help: focusing JInternalFrames

I am creating a paint program and it's just about done except there is one thing that is kind of annoying. The program consists of a JFrame with a JDesktopPane set and all editable images reside in JInternalFrames. When I want to say paint into an image, I have to click it twice: once to select the JIF, and again to start painting. This is both counterintuitive and slows you down. Typically you'd just immediately start painting on the first click.

The root of the problem is the initial click on a JIF does not generate a MouseEvent, at least not in any way that I can muster, it doesn't even appear to generate a FocusEvent, and InternalFrameEvent's not any help. I'm starting to think this isn't possible. I may be able to shift the mouse listening up to the JFrame and have it manually handle mouse events for its children, but I'd prefer to avoid that.

I've been able to accomplish sloppy focus, which isn't all too bad and with only one image open it's exactly what I want. With more than one it's a bit unexpected unless you're one of those weird Unix folks that likes sloppy focus

That's just done with a call to setSelected() in mouseEntered().

This is a decent skeleton of my code. An ImageBuffer gets a mouse event, asks for the current active tool and passes the event to the tool, who then manipulates the image based on the mouse event and its current state.

Any ideas appreciated.

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class ImageBuffer extends JInternalFrame implements MouseListener {
      ...
      // normally does nothing, for sloppy focus does setSelected() as below
      public void mouseEntered(MouseEvent me) {
            try {
                  setSelected(true);
            } catch(Exception e) {}
      }
      
      public void mousePressed(MouseEvent me){
            Tool t = ToolBox.getCurrentTool();  // such as paint brush
            
            t.imagePressed(me, this);
      }
      
      public void mouseDragged(MouseEvent me){
            Tool t = ToolBox.getCurrentTool();
            
            t.imageDragged(me, this);
      }      
      ...
}

class PaintBrush extends Tool {
      public void imagePressed(MouseEvent me, ImageBuffer buff) {
            buff.setPixel(...);
      }
      
      public void imageDragged(MouseEvent me, ImageBuffer buff) {
            buff.setLine(...);
      }
}