Java 第二次作业

菜单栏组件

    菜单按钮(MenuComponent)是一种特殊组建，只能被放在一种称为“菜单容器”的组件里。

1.菜单栏
    菜单栏(MenuBar)是窗口中的主菜单，用来包容一组子菜单，它只有一个构造方法：
    MuneBar()
    菜单栏不支持事件监听程序，在菜单栏区域产生的所有事件都会被菜单栏自动处理。

2.菜单
    菜单(Menu)中最基本的是下拉菜单。下拉菜单可以分为两种类型，一种是tear-off菜单，另一种是非tea-off菜单。二者的区别在于：当鼠标键被释放后，tear-off菜单的内容仍然显示在屏幕上。
    菜单有三种构造方式：
    (1)public Menu()构造一个不带标签的非tear-off菜单。
    (2)public Menu(String label)构造一个带指定标签的非tear-off标签，菜单的标签由String型参数指定。
    (3)public Menu(String label,boolean tearOff)构造一个带指定标签的菜单，菜单的标签由String型参数指定。boolean型参数指定菜单是否为tear-off型菜单。
    菜单可以被加入菜单栏或者另一个菜单中。通过MenuBar类中定义的setHelpMenu()方法可以指定某个菜单为帮助菜单。

3.菜单项
    如果将整个菜单系统看作一棵树，那么菜单项(MenuItem)就是这棵树的叶子。菜单项通常被加入菜单中，它有三种构造方式：
    (1)public MenuItem()创造一个没有标签和快捷方式的菜单项
    (2)public MenuItem(String label)创建一个带标签但是没有快捷方式的菜单项
    (3)public MenuItem(String label,MenuShortcut s)创建一个带标签和快捷方式的菜单项
    当菜单中的菜单项被选中时，将会引发一个ActionEvent事件，因此通常需要为菜单项注册ActionListener以便对事件作出反应。

 * @author slinm wolf
 *
 */

package imageViewer;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;

import javax.swing.*;

public class ImageViewer{
private JFrame frame;

public ImageViewer(){
makeFrame();
}

private void makeFrame(){
frame = new JFrame("我不愿作程序猿");
makeMenuBar(frame);
Container contentPane = frame.getContentPane();
contentPane.setLayout(new BorderLayout(5,5));


JPanel panelWest = new JPanel (new FlowLayout(FlowLayout.LEFT));
JPanel panelInWest = new JPanel(new GridLayout(3,1));
JButton a = new JButton("迷茫");
JButton b = new JButton("放弃");
JButton c = new JButton("NEVER GIVE UP");
panelInWest.add(a);
panelInWest.add(b);
panelInWest.add(c);
panelWest.add(panelInWest);
contentPane.add(panelWest,BorderLayout.WEST);



JLabel statusLabel1 =new JLabel("我是学渣");
contentPane.add(statusLabel1,BorderLayout.SOUTH);

Frame frm = null;
final JDialog dlg1 = new JDialog(frm,"结局1");
final JDialog dlg2 = new JDialog(frm,"结局2");
final JDialog dlg3 = new JDialog(frm,"结局3");
dlg1.setBounds(470,220,260,150);
dlg1.setLayout(null);
dlg1.setModal(true);
dlg2.setBounds(470,220,260,150);
dlg2.setLayout(null);
dlg2.setModal(true);
dlg3.setBounds(470,220,260,150);
dlg3.setLayout(null);
dlg3.setModal(true);

a.addActionListener(new ActionListener(){

@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
dlg1.setVisible(true);

}});

JButton btn1 = new JButton("You will be a loser.");


btn1.setBounds(30,50,160,30);
btn1.addActionListener(new ActionListener(){

@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
dlg1.setVisible(false);
}});
dlg1.add(btn1);

b.addActionListener(new ActionListener(){

@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
dlg2.setVisible(true);

}});

JButton btn2 = new JButton("You always are a loser.");


btn2.setBounds(30,50,200,30);
btn2.addActionListener(new ActionListener(){

@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
dlg2.setVisible(false);
}});
dlg2.add(btn2);


c.addActionListener(new ActionListener(){

@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
dlg3.setVisible(true);

}});

JButton btn3 = new JButton("You will succeed.");


btn3.setBounds(30,50,160,30);
btn3.addActionListener(new ActionListener(){

@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
dlg3.setVisible(false);
}});
dlg3.add(btn3);



frame.setSize(260, 300);
Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
frame.setLocation(d. width/2 - frame.getWidth()/2, d.height/2 - frame.getHeight()/2);
frame.setVisible(true);
}

private void makeMenuBar(JFrame frame) {
final int SHORTCUT_MASK =
Toolkit.getDefaultToolkit().getMenuShortcutKeyMask();

JMenuBar menubar = new JMenuBar();
frame.setJMenuBar(menubar);

// create the File menu
JMenu menuFile = new JMenu("菜单");
menubar.add(menuFile);

JMenuItem itemOpen = new JMenuItem("打开");

itemOpen.addActionListener(new ActionListener(){

@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
openFile();
}

private void openFile() {
// TODO Auto-generated method stub

}});
menuFile.add(itemOpen);

JMenuItem itemClose = new JMenuItem("关闭");
menuFile.add(itemClose);
menuFile.addSeparator();

JMenuItem itemQuit = new JMenuItem("退出");
itemQuit.addActionListener(new ActionListener(){

@Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
System.exit(0);
}});
menuFile.add(itemQuit);

}

public static void main(String[] args){
new ImageViewer();
}

}