高级组件——弹出式菜单JPopupMenu

弹出式菜单JPopupMenu，需要用到鼠标事件。
MouseListener必须要实现所有接口，MouseAdapter是类，只写你关心的方法，即MouseAdapter实现了MouseListener中的方法

import javax.swing.*;
import java.awt.*;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;public class Demo extends JFrame {public Demo() {setTitle("弹出式菜单");setBounds(100, 100, 300, 200);setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);Container c = getContentPane();JLabel label = new JLabel("请单击鼠标右键");c.add(label, BorderLayout.CENTER);JPopupMenu popupMenu = new JPopupMenu();//弹出式菜单JMenuItem copyItem=new JMenuItem("复制");popupMenu.add(copyItem);JMenu pasteItem=new JMenu("粘贴");popupMenu.add(pasteItem);JMenuItem pasteItem1=new JMenuItem("只粘贴文本");JMenuItem pasteItem2=new JMenuItem("源格式粘贴");pasteItem.add(pasteItem1);pasteItem.add(pasteItem2);//MouseListener必须要实现所有接口,MouseAdapter是类，只写你关心的方法，即MouseAdapter实现了MouseListener中的方法c.addMouseListener(new MouseAdapter() {//为窗体顶层容器添加鼠标监听public void mouseReleased(MouseEvent e) {//鼠标释放if (e.isPopupTrigger()) {//判断鼠标事件是否是弹出菜单触发,若是则在释放鼠标的位置弹出菜单
                    popupMenu.show(e.getComponent(), e.getX(), e.getY());}}});}public static void main(String[] args) {Demo frame = new Demo();frame.setVisible(true);}
}