panel.setLayout(null);
panel.setLayout(new FlowLayout(0, 0, 0));
    public void show()    {      // We insert a JPanel between the layered pane and the contents so we      // can fiddle with the setLocation() method without disturbing a      // JPopupMenu (which overrides setLocation in an unusual manner).      if (panel == null)        {          panel = new JPanel();          panel.setLayout(null);        }      panel.add(contents);      panel.setSize(contents.getSize());      Point layeredPaneLoc = layeredPane.getLocationOnScreen();      panel.setLocation(x - layeredPaneLoc.x, y - layeredPaneLoc.y);      layeredPane.add(panel, JLayeredPane.POPUP_LAYER);    }