checkedboxmenudemo.java

java课程的资料以及实验的代码

import java.awt.*;
import java.awt.event.*;
import javax.swing.ImageIcon;
import javax.swing.*;
public class CheckedBoxMenuDemo extends JFrame implements ActionListener,ItemListener
{
	ImageIcon icon=new ImageIcon("warning.gif");
	JTextField msg=new JTextField();
	JMenuBar mb=new JMenuBar();
	JMenu m1=new JMenu("File");
	JMenu m2=new JMenu("二级菜单");
	JMenuItem item=new JMenuItem("普通菜单项");
	JCheckBoxMenuItem checkbox=new JCheckBoxMenuItem("复选菜单项");
	JMenuItem exit=new JMenuItem("退出");
	public CheckedBoxMenuDemo()
	{
		setIconImage(icon.getImage());
		addWindowListener(new WindowAdapter()
		{
			public void windowClosing(WindowEvent e)
			{
				System.exit(0);
			}
		});
		Container c=this.getContentPane();
		setTitle("菜单综合使用");
		setSize(350,200);
		c.add(msg);
		mb.add(m1);
		m1.add(m2);
		checkbox.setState(true);
		m1.add(item);
		m1.setMnemonic('F');//此方法用于设定快捷键
		item.setAccelerator(KeyStroke.getKeyStroke('I',java.awt.Event.CTRL_MASK,false));
		m1.add(checkbox);
		m1.addSeparator();
		m1.add(exit);
		m2.add("菜单项A");
		m2.add("菜单项B");
		item.addActionListener(this);
		checkbox.addActionListener(this);
		exit.addActionListener(this);
		this.setJMenuBar(mb);
		show();
				
	}
	public void actionPerformed(ActionEvent e)
	{
		if(e.getSource()==exit)
		System.exit(0);
		msg.setText(e.getActionCommand()+"is opened");
			}
public void itemStateChanged(ItemEvent e)
{
	if(e.getSource()==checkbox)
	if(checkbox.getState())
	msg.setText(checkbox.getText()+"is selected");
	else
	msg.setText(msg.getText()+"is canceled");
    }	
    public static void main(String []args)
   {
	new CheckedBoxMenuDemo();
	}
}