1   // joi/10/joi/ButtonListener.java                         
2   //                                                            
3   //                                                            
4   // Copyright 2003 Bill Campbell and Ethan Bolker                         
5                                                               
6   import java.awt.event.*;
7   
8   /**
9    * A simple listener for responding to button presses.
10   * It knows the Panel on which the button lives, and 
11   * responds to button events by sending a changeMessage() 
12   * to that Panel. 
13   *
14   * @version 10.2
15   */
16  
17  public class ButtonListener implements ActionListener
18  {
19      private JOIPanel panel;  // the Panel containing the Button
20  
21      /**
22       * Construct the ButtonListener.
23       *
24       * @param panel the Panel on which this Button will act.
25       */
26  
27      public ButtonListener( JOIPanel panel )
28      {
29          this.panel = panel;
30      }
31  
32      /**
33       * Defines the ActionListener behavior that must be implemented.
34       *
35       * When a user pushes the Button that we're listening to, 
36       * send a changeMessage() message to the Panel.
37       *
38       * @param e the "event" when the button is pressed.
39       */
40  
41      public void actionPerformed( ActionEvent e )
42      {
43          panel.changeMessage();
44      }
45  }
46