public void itemStateChanged(ItemEvent event) { CheckboxMenuItem theMenuItem = (CheckboxMenuItem) (event.getSource()); String strIndex = theMenuItem .getActionCommand() .substring(theMenuItem.getActionCommand().lastIndexOf('.') + 1); int index = (new Integer(strIndex)).intValue(); if (theMenuItem.getState()) { ((Component) visibleMapLayers.elementAt(index)).setVisible(true); } else { ((Component) visibleMapLayers.elementAt(index)).setVisible(false); } System.out.println("Action = " + theMenuItem.getActionCommand()); System.out.println(" = " + theMenuItem.getState()); }