Java GUI编程菜单组件实例详解

import java.awt.*;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

public class SimpleMenu {

     //创建窗口

     private Frame frame = new Frame( "这里测试菜单相关组件" );

     //创建菜单条组件

     private MenuBar menuBar = new MenuBar();

     //创建文件菜单组件

     private Menu fileMenu = new Menu( "文件" );

     //创建编辑菜单组件

     private Menu editMenu = new Menu( "编辑" );

     //创建新建菜单项

     private MenuItem newItem = new MenuItem( "新建" );

     //创建保存菜单项

     private MenuItem saveItem = new MenuItem( "保存" );

     //创建退出菜单项

     private MenuItem exitItem = new MenuItem( "退出" );

     //创建自动换行选择框菜单项

     private CheckboxMenuItem autoWrap = new CheckboxMenuItem( "自动换行" );

     //创建复制菜单项

     private MenuItem copyItem = new MenuItem( "复制" );

     //创建粘贴菜单项

     private MenuItem pasteItem = new MenuItem( "粘贴" );

     //创建格式菜单

     private Menu formatMenu = new Menu( "格式" );

     //创建注释菜单项

     private MenuItem commentItem = new MenuItem( "注释" );

     //创建取消注释菜单项

     private MenuItem cancelItem = new MenuItem( "取消注释" );

     //创建一个文本域

     private TextArea ta = new TextArea( 6 , 40 );

     public void init(){

         //定义菜单事件监听器

         ActionListener listener = new ActionListener() {

             @Override

             public void actionPerformed(ActionEvent e) {

                 String command = e.getActionCommand();

                 ta.append( "单击[" +command+ "]菜单\n" );

                 if (command.equals( "退出" )){

                     System.exit( 0 );

                 }

             }

         };

         //为注释菜单项和退出菜单项注册监听器

         commentItem.addActionListener(listener);

         exitItem.addActionListener(listener);

         //为文件菜单fileMenu添加菜单项

         fileMenu.add(newItem);

         fileMenu.add(saveItem);

         fileMenu.add(exitItem);

         //为编辑菜单editMenu添加菜单项

         editMenu.add(autoWrap);

         editMenu.add(copyItem);

         editMenu.add(pasteItem);

         //为格式化菜单formatMenu添加菜单项

         formatMenu.add(commentItem);

         formatMenu.add(cancelItem);

         //将格式化菜单添加到编辑菜单中，作为二级菜单

         editMenu.add( new MenuItem( "-" ));

         editMenu.add(formatMenu);

         //将文件菜单和编辑菜单添加到菜单条中

         menuBar.add(fileMenu);

         menuBar.add(editMenu);

         //把菜单条设置到frame窗口上

         frame.setMenuBar(menuBar);

         //把文本域添加到frame中

         frame.add(ta);

         //设置frame最佳大小并可见

         frame.pack();

         frame.setVisible( true );

     }

     public static void main(String[] args) {

         new SimpleMenu().init();

     }

}

import java.awt.*;

import java.awt.event.MouseAdapter;

import java.awt.event.MouseEvent;

public class PopupMenuTest {

     private Frame frame = new Frame( "这里测试PopupMenu" );

     // 创建PopubMenu菜单

     private PopupMenu popupMenu = new PopupMenu();

     // 创建菜单条

     private MenuItem commentItem = new MenuItem( "注释" );

     private MenuItem cancelItem = new MenuItem( "取消注释" );

     private MenuItem copyItem = new MenuItem( "复制" );

     private MenuItem pasteItem = new MenuItem( "保存" );

     // 创建一个文本域

     private TextArea ta = new TextArea( "我爱中华！！！" , 6 , 40 );

     // 创建一个Panel

     private Panel panel = new Panel();

     public void init() {

         // 把菜单项添加到PopupMenu中

         popupMenu.add(commentItem);

         popupMenu.add(cancelItem);

         popupMenu.add(copyItem);

         popupMenu.add(pasteItem);

         // 设置panel大小

         panel.setPreferredSize( new Dimension( 300 , 100 ));

         // 把PopupMenu添加到panel中

         panel.add(popupMenu);

         // 为panel注册鼠标事件

         panel.addMouseListener( new MouseAdapter() {

             @Override

             public void mouseReleased(MouseEvent e) {

                 boolean flag = e.isPopupTrigger();

                 // 判断当前鼠标操作是不是触发PopupMenu的操作

                 if (flag) {

                     // 让PopupMenu显示在panel上，并且跟随鼠标事件发生的地方显示

                     popupMenu.show(panel, e.getX(), e.getY());

                 }

             }

         });

         // 把ta添加到frame中间区域中

         frame.add(ta);

         // 把panel添加到frame底部

         frame.add(panel, BorderLayout.SOUTH);

         // 设置frame最佳大小，并可视；

         frame.pack();

         frame.setVisible( true );

     }

     public static void main(String[] args) {

         new PopupMenuTest().init();

     }

}