Button, the Button
fires an ActionEvent. To be ready to respond to this event you
must register an ActionListener with the Button.
For example,
Button beep = new Button("Beep");
add(beep); // add the button to the layout
beep.addActionListener(myActionListener); // assign the button a listener
myActionListener is a reference to an object which implements the
java.awt.event.ActionListener interface. This interface specifies
a single method, actionPerformed():
public abstract void actionPerformed(ActionEvent e)
The ActionListener object does something as a result of the
ActionEvent the button press fired. For example, the following
class beeps when it gets an ActionEvent:
import java.awt.*;
import java.awt.event.*;
public class BeepAction implements ActionListener {
public void actionPerformed(ActionEvent e) {
Toolkit.getDefaultToolkit().beep();
}
}