GUI菜单练习

import java.awt.*;import java.awt.event.*;public class MyMenuDemo {    private Frame f;    private MenuBar mb;    private Menu m,subMenu;    private MenuItem closeItem,subItem;    public MyMenuDemo()    {        init();    }    public void init()    {        f=new Frame("my window");        f.setBounds(200, 100, 500, 400);        mb=new MenuBar();        m=new Menu("编辑");        subMenu=new Menu("子菜单");        closeItem=new MenuItem("关闭");        subItem=new MenuItem("子条目");        mb.add(m);        m.add(subMenu);        m.add(closeItem);        subMenu.add(subItem);        f.setMenuBar(mb);        f.setVisible(true);             myEvent();    }    public void myEvent()    {        f.addWindowListener(new WindowAdapter()        {            public void windowClosing(WindowEvent e)            {                System.exit(0);            }        });        closeItem.addActionListener(new ActionListener()        {            @Override            public void actionPerformed(ActionEvent e) {                // TODO Auto-generated method stub                System.exit(0);            }        });    }    public static void main(String[] args) {        // TODO Auto-generated method stub        new MyMenuDemo();    }}

点击关闭条目，退出my window。