设计一个窗口，窗口中心添加一个JTextArea，另添加4个菜单，每个菜单都有菜单项，每个菜单项都对应有快捷键，选择某个菜单项时，窗口中心的文本区都显示对应的信息。
1 import java.awt.event.ActionEvent; 2 import java.awt.event.ActionListener; 3 import java.awt.event.KeyEvent; 4 5 import javax.swing.JMenuBar; 6 import javax.swing.JMenu; 7 import javax.swing.JMenuItem; 8 import javax.swing.JOptionPane; 9 import javax.swing.JFrame; 10 import javax.swing.JTextArea; 11 import javax.swing.JScrollPane; 12 import java.awt.MenuShortcut; 13 14 class ExMyFrame66 extends JFrame implements ActionListener { 15 JTextArea tArea; 16 JScrollPane scrollpane; 17 18 JMenuBar menubar ; //菜单栏 19 JMenu menuFile; //文件菜单 20 JMenu menuEdit; //编辑菜单 21 JMenu menuWin; //窗口菜单 22 JMenuItem menuItemOpen; //打开 23 JMenuItem menuItemSave; //保存 24 JMenuItem menuItemNew; //新建 25 JMenuItem menuItemCopy; //复制 26 JMenuItem menuItemPaste; //粘贴 27 JMenuItem menuItemCut; //剪切 28 JMenuItem menuItemAbout; //关于 29 JMenuItem menuItemExit; //退出 30 31 MenuShortcut mShorcutFile; 32 MenuShortcut mShorcutEdit; 33 MenuShortcut mShorcutWin; 34 MenuShortcut mShorcutNew; 35 MenuShortcut mShorcutOpen; 36 MenuShortcut mShorcutSave; 37 MenuShortcut mShorcutCut; 38 MenuShortcut mShorcutCopy; 39 MenuShortcut mShorcutPaste; 40 MenuShortcut mShorcutAbout; 41 MenuShortcut mShorcutExit; 42 43 ExMyFrame66(){ 44 setSize(400,300); 45 setTitle("菜单栏练习"); 46 //初始化文本区、滚动面板 47 tArea = new JTextArea("文本编辑区"); 48 tArea.setEditable(true); 49 scrollpane = new JScrollPane(tArea); 50 this.add(scrollpane); 51 52 //初始化菜单栏、菜单、菜单项、菜单项快捷键 53 menubar = new JMenuBar(); 54 menuFile = new JMenu("文件"); 55 menuEdit = new JMenu("编辑"); 56 menuWin = new JMenu("窗口"); 57 58 menuItemNew = new JMenuItem("新建") ; 59 menuItemOpen = new JMenuItem("打开") ; 60 menuItemSave = new JMenuItem("保存") ; 61 menuItemCut = new JMenuItem("剪切") ; 62 menuItemCopy = new JMenuItem("复制") ; 63 menuItemPaste = new JMenuItem("粘贴") ; 64 menuItemAbout = new JMenuItem("关于") ; 65 menuItemExit = new JMenuItem("退出") ; 66 67 super.setJMenuBar(menubar); // 将菜单栏添加到JFrame(super)或者JFrame的子类也即“ExMyFrame66” 68 69 // 将菜单添加到菜单栏 70 menubar.add(menuFile); 71 menubar.add(menuEdit); 72 menubar.add(menuWin); 73 74 // 将菜单项添加到菜单 75 menuFile.add(menuItemNew); 76 menuFile.add(menuItemOpen); 77 menuFile.add(menuItemSave); 78 menuEdit.add(menuItemCut); 79 menuEdit.add(menuItemCopy); 80 menuEdit.add(menuItemPaste); 81 menuWin.add(menuItemAbout); 82 menuWin.add(menuItemExit); 83 84 //将菜单及菜单项快捷键绑定到菜单与菜单项上 85 mShorcutFile = new MenuShortcut(KeyEvent.VK_F); 86 mShorcutEdit = new MenuShortcut(KeyEvent.VK_E); 87 mShorcutWin = new MenuShortcut(KeyEvent.VK_W); 88 mShorcutOpen = new MenuShortcut(KeyEvent.VK_O); 89 mShorcutNew = new MenuShortcut(KeyEvent.VK_N); 90 mShorcutSave = new MenuShortcut(KeyEvent.VK_S); 91 mShorcutCopy = new MenuShortcut(KeyEvent.VK_C); 92 mShorcutCut = new MenuShortcut(KeyEvent.VK_X); 93 mShorcutPaste = new MenuShortcut(KeyEvent.VK_V); 94 mShorcutAbout = new MenuShortcut(KeyEvent.VK_A); 95 mShorcutExit = new MenuShortcut(KeyEvent.VK_Q); 96 97 98 //注册菜单项监听器 99 //menuFile.addActionListener(this); //菜单Menu不能添加事件触发器，只有菜单项MenuItem才能添加ActionListener触发器 100 //menuEdit.addActionListener(this); 101 //menuWin.addActionListener(this); 102 menuItemNew.addActionListener(this); 103 menuItemOpen.addActionListener(this); 104 menuItemSave.addActionListener(this); 105 menuItemCut.addActionListener(this); 106 menuItemCopy.addActionListener(this); 107 menuItemPaste.addActionListener(this); 108 menuItemAbout.addActionListener(this); 109 menuItemExit.addActionListener(this); 110 111 } 112 113 @Override 114 public void actionPerformed(ActionEvent e) { 115 // TODO Auto-generated method stub 116 //如果ActionListener触发的事件来源是菜单或菜单项，则显示菜单项的名称 117 if (e.getSource().getClass() == (new JMenu()).getClass() || 118 e.getSource().getClass() == (new JMenuItem()).getClass()){ 119 tArea.setText("选择了"+e.getActionCommand()); 120 } 121 122 //设置“退出”菜单项的事件解释 123 if (e.getSource() == menuItemExit){ 124 int result = JOptionPane.showConfirmDialog(this, "确定要退出吗？","退出确认",JOptionPane.YES_NO_OPTION);//this代表对话框依赖的父窗口 125 if (result == JOptionPane.YES_OPTION){ 126 System.exit(0); 127 } 128 } 129 } 130 131 }