1 import java.awt.event.*;
2 import javax.swing.*;
3
4 public class SimpleGui2B implements ItemListener {
5
6 JCheckBox checkbox;
7 public static void main(String[] args){
8 SimpleGui2B littleCase=new SimpleGui2B();
9 littleCase.go();
10
11 }
12 public void go(){
13 JFrame frame=new JFrame();
14 checkbox=new JCheckBox("I'm a checkbox");
15 checkbox.addItemListener(this);//向ckeckbox注册,为什么也要用addActionListener这个函数呢?
16
17 frame.getContentPane().add(checkbox);
18 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
19 frame.setSize(300,300);
20 frame.setVisible(true);
21
22
23 }
24 /*public void actionPerformed(ActionEvent event){
25 checkbox.setText("I've been clicked!");
26 }
27 */
28 public void windowClosing(ActionEvent event){
29 checkbox.paintImmediately(null);
30 }
31 @Override
32 public void itemStateChanged(ItemEvent arg0) {
33 checkbox.setText("I've been changed!");
34 // TODO Auto-generated method stub
35
36 }
37
38 //复选框勾选,代表要关闭windowClosing(),就是说当选中复选框时,
39 //如何实现windowClosing()这个
40 }