Button Action Handler at the Component Level

Java Swing Tutorials - Herong's Tutorial Examples

∟Button Action Handler at the Component Level

This section provides a tutorial example on how to create a button to handle actions by adding the ActionListener interface to the button component.

One way to handle button actions is to add an action listener to the button object. An action listener is an object of any class that implements the ActionListener interface.

The following program shows you how to extend the JButton class to implement the ActionListener class:

/* JButtonAction1.java
 * Copyright (c) 1997-2024 HerongYang.com. All Rights Reserved.
 */
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class JButtonAction1 {
   public static void main(String[] a) {
      JFrame f = new JFrame("My Switch Button");
      f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      JButton b = new MyButton();
      f.getContentPane().add(b);
      f.pack();
      f.setVisible(true);
   }
   private static class MyButton extends JButton 
      implements ActionListener {
       String text = "On";
       public MyButton() {
          super();
          setText(text);
          addActionListener(this);
       }
       public void actionPerformed(ActionEvent e) {
          if (text.equals("On")) text = "Off";
          else text = "On"; 
          setText(text);
       }
   }
}