SWING - JRadioButton 类

简介

JRadioButton 类是单选按钮的实现——一个可以选择或取消选择的项目，它向用户显示其状态。

类声明

以下是 javax.swing.JRadioButton 类的声明 −

public class JRadioButton
   extends JToggleButton
      implements Accessible

类构造函数

类方法

继承的方法

这个类继承了以下类的方法 −

• javax.swing.AbstractButton
• javax.swing.JToggleButton
• javax.swing.JComponent
• java.awt.Container
• java.awt.Component
• java.lang.Object

JRadioButton 示例

在 D:/ > SWING > com > tutorialspoint > gui > 中使用您选择的任何编辑器创建以下 Java 程序

SwingControlDemo.java

package com.tutorialspoint.gui;
 
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
 
public class SwingControlDemo {
   private JFrame mainFrame;
   private JLabel headerLabel;
   private JLabel statusLabel;
   private JPanel controlPanel;
   
   public SwingControlDemo(){
      prepareGUI();
   }
   public static void main(String[] args){
      SwingControlDemo  swingControlDemo = new SwingControlDemo();      
      swingControlDemo.showRadioButtonDemo();
   }
   private void prepareGUI(){
      mainFrame = new JFrame("Java Swing Examples");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));
      
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
            System.exit(0);
         }        
      });    
      headerLabel = new JLabel("", JLabel.CENTER);        
      statusLabel = new JLabel("",JLabel.CENTER);    
      statusLabel.setSize(350,100);

      controlPanel = new JPanel();
      controlPanel.setLayout(new FlowLayout());

      mainFrame.add(headerLabel);
      mainFrame.add(controlPanel);
      mainFrame.add(statusLabel);
      mainFrame.setVisible(true);  
   }
   private void showRadioButtonDemo(){
      headerLabel.setText("Control in action: RadioButton"); 

      final JRadioButton radApple = new JRadioButton("Apple", true);
      final JRadioButton radMango = new JRadioButton("Mango");
      final JRadioButton radPeer = new JRadioButton("Peer");

      radApple.setMnemonic(KeyEvent.VK_C);
      radMango.setMnemonic(KeyEvent.VK_M);
      radPeer.setMnemonic(KeyEvent.VK_P);

      radApple.addItemListener(new ItemListener() {
         public void itemStateChanged(ItemEvent e) {         
            statusLabel.setText("Apple RadioButton: " 
               + (e.getStateChange()==1?"checked":"unchecked"));
         }           
      });
      radMango.addItemListener(new ItemListener() {
         public void itemStateChanged(ItemEvent e) {             
            statusLabel.setText("Mango RadioButton: " 
               + (e.getStateChange()==1?"checked":"unchecked")); 
         }           
      });
      radPeer.addItemListener(new ItemListener() {
         public void itemStateChanged(ItemEvent e) {             
            statusLabel.setText("Peer RadioButton: " 
               + (e.getStateChange()==1?"checked":"unchecked"));
         }           
      });
      
      //Group the radio buttons.
      ButtonGroup group = new ButtonGroup();
      
      group.add(radApple);
      group.add(radMango);
      group.add(radPeer);

      controlPanel.add(radApple);
      controlPanel.add(radMango);
      controlPanel.add(radPeer);       

      mainFrame.setVisible(true);  
   }
}

使用命令提示符编译程序。 转到 D:/ > SWING 并键入以下命令。

D:\SWING>javac com\tutorialspoint\gui\SwingControlDemo.java

如果没有报错，说明编译成功。 使用以下命令运行程序。

D:\SWING>java com.tutorialspoint.gui.SwingControlDemo

验证以下输出。

❮ SWING 控件