svoid makeMenuFullyDynamic(final JMenu menu, final VF1<JMenu> populate) {
  addMenuListener(menu, new MenuListener {
    public void menuSelected(MenuEvent e) {
      clearMenu(menu);
      callF(populate, menu);
    }
    
    public void menuDeselected(MenuEvent e) {
      clearMenu(menu);
    }
    
    public void menuCanceled(MenuEvent e) {
      clearMenu(menu);
    }
  });
}

Began life as a copy of #1019361