帮忙看一下，我运行后得出的结果不太对

[tangyuanamen]

import javax.swing.*;
import java.awt.event.*;

class JRadioButtonDemo implements ActionListener
{
private JFrame jframe;
private JPanel jpl;
private JRadioButton jrb1,jrb2,jrb3,jrb4;
private JLabel jlb;
private ButtonGroup bg;
public JRadioButtonDemo()
{
jframe=new JFrame("JRadioButton Demo");
jpl = new JPanel();
jlb= new JLabel("Please choose your answer");
bg = new ButtonGroup();

jrb1 = new JRadioButton("A");
jrb1.addActionListener(this);
jpl.add(jrb1);

jrb2 = new JRadioButton("B");
jrb1.addActionListener(this);
jpl.add(jrb2);

jrb3 = new JRadioButton("C");
jrb1.addActionListener(this);
jpl.add(jrb3);

jrb4 = new JRadioButton("D");
jrb1.addActionListener(this);
jpl.add(jrb4);

bg.add(jrb1);bg.add(jrb2);bg.add(jrb3);bg.add(jrb4);

jpl.add(jlb);
jframe.getContentPane().add(jpl);
jframe.pack();
jframe.setVisible(true);
jframe.setDefaultCloseOperation(jframe.EXIT_ON_CLOSE);
}

public void actionPerformed(ActionEvent e)
{
jlb.setText("You choose the answer:"+e.getActionCommand());
}
public static void main(String[] args)
{
new JRadioButtonDemo();
}
}
我运行后得出的结果不太对，只有点A时有反映，那里错了，谢谢

[lfcai]

加监听器的对象不对吧，全加到jrb1上去了
应该为
jrb1 = new JRadioButton("A");
jpl.add(jrb1);
jrb1.addActionListener(this);

jrb2 = new JRadioButton("B");
jpl.add(jrb2);
jrb2.addActionListener(this);

jrb3 = new JRadioButton("C");
jpl.add(jrb3);
jrb3.addActionListener(this);

jrb4 = new JRadioButton("D");
jpl.add(jrb4);
jrb4.addActionListener(this);

[jiuxiaofei]

jrb1 = new JRadioButton("A");
jrb1.addActionListener(this);
jpl.add(jrb1);

jrb2 = new JRadioButton("B");
jrb1.addActionListener(this);
jpl.add(jrb2);

jrb3 = new JRadioButton("C");
jrb1.addActionListener(this);
jpl.add(jrb3);

jrb4 = new JRadioButton("D");
jrb1.addActionListener(this);
jpl.add(jrb4);
==================

addActionListener() 方法统统加到“ jrb1”上了。。。 ctrl+c ctrl+v的后遗症！！

[zdjray]

请详细描述一下

[tangyuanamen]

呵呵，谢谢