menu1.java

一个使用菜单程序

import java.awt.*;
import java.awt.event.*;
class Menu1 extends WindowAdapter implements ActionListener,MouseListener
{
    Frame f;
    MenuBar mb1;
    Menu mf1,me1,mh1,md1;
    CheckboxMenuItem cbmi1;
    PopupMenu pm1;
    Dialog d;
    public void display()
    {
        f = new Frame("Menu");
        f.setSize(240,180);
        f.setLocation(400,200);
        f.setBackground(Color.lightGray);
        f.addWindowListener(this);
        f.addMouseListener(this);        //为框架f注册鼠标事件监听程序
        f.setVisible(true);
        pm1 = new PopupMenu("Popup");    //生成一个弹出式菜单对象
        pm1.add(new MenuItem("Cut"));    //加入菜单项
        pm1.add(new MenuItem("Copy"));
        pm1.add(new MenuItem("Paste"));
        pm1.addSeparator();              //加分隔线
        pm1.add(new MenuItem("Exit"));
        pm1.addActionListener(this);     //为菜单注册事件监听程序
        f.add(pm1);                      //框架f上添加弹出式菜单
        d = new Dialog(f,"Dialog Example",true);
        d.add(new Label("打开一个对话框"),"Center");
        d.setSize(120,60);
        d.setLocation(500,300);
        d.addWindowListener(this);      //为对话框d注册事件监听程序
        addmyMenu();
    }        
    public void addmyMenu()
    {
        mb1 = new MenuBar();             //生成一个菜单栏
        f.setMenuBar(mb1);               //框架f上添加菜单栏
        mf1 = new Menu("File");          //生成一个菜单
        me1 = new Menu("Edit");
        mh1 = new Menu("Help");
        mb1.add(mf1);                    //菜单栏中加入菜单
        mb1.add(me1);
        mb1.add(mh1);
        mf1.add(new MenuItem("Open"));   //生成菜单项并加入到菜单
        mf1.add(new MenuItem("Save",new MenuShortcut(KeyEvent.VK_S)));
        mf1.addSeparator();              //加分隔线
        md1 = new Menu("Delete");
        mf1.add(md1);                    //菜单加入到菜单中成为二级菜单
        cbmi1 = new CheckboxMenuItem("Bold",true);
        mf1.add(cbmi1);
        mf1.add(new MenuItem("Exit"));
        mf1.addActionListener(this);     //为菜单注册事件监听程序
        me1.add(new MenuItem("Cut"));
        me1.add(new MenuItem("Exit"));
        me1.addActionListener(this);
    }
    public void windowClosing(WindowEvent e)
    {
        if(e.getSource()==d)
             d.setVisible(false);
        else
             System.exit(0); 
    }
    public void actionPerformed(ActionEvent e)
    {                                    //选择菜单项时触发
        if(e.getActionCommand()=="Open")
            d.setVisible(true);
        if(e.getActionCommand()=="Exit")
            System.exit(0);
    }
    public void mouseClicked(MouseEvent mec)
    {                                    //单击鼠标时触发
        if (mec.getModifiers()==mec.BUTTON3_MASK)  //单击的是鼠标右键
            pm1.show(f,mec.getX(),mec.getY()); //在鼠标单击处显示菜单
    }
    public void mousePressed(MouseEvent mep)    {    }
    public void mouseReleased(MouseEvent mer)   {    }
    public void mouseEntered(MouseEvent mee)    {    } 
    public void mouseExited(MouseEvent mex)     {    }
    public void mouseDragged(MouseEvent med)    {    }
    public static void main(String arg[])
    {
        (new Menu1()).display();
    }
}