Question

Java程序求助!(单选加监听)

import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;

public class jj extends Applet implements ActionListener{
Label L1= new Label("请选择你喜欢的颜色：");
Label L2= new Label("你喜欢的颜色是:");
Label L3= new Label("界面制作人：");

TextField tf= new TextField(1);

CheckboxGroup cg=new CheckboxGroup();
Checkbox red= new Checkbox("red",true,cg);
Checkbox blue= new Checkbox("blue",false,cg);
Checkbox green= new Checkbox("green",false,cg);

Panel pa1= new Panel();
Panel pa2= new Panel();
Panel pa3= new Panel();

public void init(){
add(L1);add(pa1);add(pa2);add(pa3);
pa1.add(red);pa1.add(blue);pa1.add(green);
pa2.add(L2);pa2.add(tf);pa3.add(L3);
}

public void actionPerformed(ActionEvent e) {
if(red.getState()==true) tf.setText("red");
if(blue.getState()==true) tf.setText("blue");
if(green.getState()==true) tf.setText("green");
}
}

程序目标:
按单选框"red" "blue" "green" 其中任一,能够在 文本区域"tf"中显现出来.

Answer 1

public class jj extends Applet implements ItemListener {
Label L1 = new Label("请选择你喜欢的颜色：");
Label L2 = new Label("你喜欢的颜色是:");
Label L3 = new Label("界面制作人：");
TextField tf = new TextField(1);
CheckboxGroup cg = new CheckboxGroup();
Checkbox red = new Checkbox("red", true, cg);
Checkbox blue = new Checkbox("blue", false, cg);
Checkbox green = new Checkbox("green", false, cg);
Panel pa1 = new Panel();
Panel pa2 = new Panel();
Panel pa3 = new Panel();
public void init() {
add(L1);
add(pa1);
add(pa2);
add(pa3);
pa1.add(red);
pa1.add(blue);
pa1.add(green);
pa2.add(L2);
pa2.add(tf);
pa3.add(L3);
red.addItemListener(this);
blue.addItemListener(this);
green.addItemListener(this);
}
public void itemStateChanged(ItemEvent e) {
if (red.getState() == true)
tf.setText("red");
if (blue.getState() == true)
tf.setText("blue");
if (green.getState() == true)
tf.setText("green");
}
}

Answer 2

这个刚帮人家做过，给每个radio加个单击事件可以达成效果

追问

不明白...radio是什么?简单一点...我需要怎么改?哪一部需要加些什么符号?