Swing如何建立和使用無線電鈕?


下面的範例展示了如何在Java Swing應用程式中使用標準無線電鈕。

使用以下API -

  • JRadioButton() - 建立標準無線電鈕。
  • JRadioButton.setEnabled(false); - 禁用無線電鈕。
  • JRadioButton.setMnemonic(KeyEvent.VK_C) - 為無線電鈕設定鍵盤快捷鍵。
  • JRadioButton.setSelected(true) - 設定選中的無線電鈕。

範例:

package com.yiibai.swingdemo;

import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.LayoutManager;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;

import javax.swing.JRadioButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;

public class SwingTester {
   public static void main(String[] args) {
      createWindow();
   }

   private static void createWindow() {    
      JFrame frame = new JFrame("Swing建立和使用無線電鈕(tw511.com)");
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

      createUI(frame);
      frame.setSize(560, 200);      
      frame.setLocationRelativeTo(null);  
      frame.setVisible(true);
   }

   private static void createUI(final JFrame frame){  
      JPanel panel = new JPanel();
      LayoutManager layout = new FlowLayout();  
      panel.setLayout(layout);       

      JRadioButton radioButton1 = new JRadioButton("Java/Swing");
      JRadioButton radioButton2 = new JRadioButton("Python");
      radioButton2.setEnabled(false);
      JRadioButton radioButton3 = new JRadioButton("MySQL");
      radioButton3.setMnemonic(KeyEvent.VK_C);

      radioButton1.addActionListener(new ActionListener() {
         @Override
         public void actionPerformed(ActionEvent e) {
            Object source = e.getSource();
            JOptionPane.showMessageDialog(frame, 
               ((JRadioButton)source).getText() + ": " + ((JRadioButton)source).isSelected());
         }
      });  

      panel.add(radioButton1);
      panel.add(radioButton2);
      panel.add(radioButton3);

      frame.getContentPane().add(panel, BorderLayout.CENTER);    
   }
}

執行上面範例程式碼,得到以下結果:

創建和使用單選按鈕