ActionEvent.getActionCommand() : ActionListener « Swing Event « Java Tutorial

1. Java Tutorial
2. Swing Event
3. ActionListener

import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;

class ButtonDemo implements ActionListener {
  JButton jbtnA = new JButton("Alpha");
  JButton jbtnB = new JButton("Beta");

  ButtonDemo() {
    JFrame jfrm = new JFrame("A Button Example");
    jfrm.setLayout(new FlowLayout());
    jfrm.setSize(220, 90);
    jfrm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    jbtnA.addActionListener(this);
    jbtnB.addActionListener(this);

    jfrm.add(jbtnA);
    jfrm.add(jbtnB);

    jfrm.setVisible(true);
  }

  public void actionPerformed(ActionEvent ae) {
    String ac = ae.getActionCommand();

    if (ac.equals("Alpha")) {
      if (jbtnB.isEnabled()) {
        System.out.println("Alpha pressed. Beta is disabled.");
        jbtnB.setEnabled(false);
      } else {
        System.out.println("Alpha pressed. Beta is enabled.");
        jbtnB.setEnabled(true);
      }
    } else if (ac.equals("Beta"))
      System.out.println("Beta pressed.");
  }

  public static void main(String args[]) {
    new ButtonDemo();
  }
}

15.5.ActionListener
	15.5.1.	implements ActionListener and action class level variable
	15.5.2.	Handling an action listener
	15.5.3.	Check the event source in actionPerformed method
	15.5.4.	Use an Inner Class to handle the event
	15.5.5.	Use one inner class to handle events from two buttons
	15.5.6.	Get event source from ActionEvent
	15.5.7.	Add action listener to JTextField
	15.5.8.	ComboBox with ActionListener
	15.5.9.	ActionEvent.getActionCommand()
	15.5.10.	Using an inner ActionListener class.