//: c13:DynamicEvents.java
// From Thinking in Java, 2nd Edition
// Available at http://www.BruceEckel.com
// (c) Bruce Eckel 1999
// Copyright notice in Copyright.txt
// You can change event behavior dynamically.
// Also shows multiple actions for an event.
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;

public class DynamicEvents extends JFrame{
  ArrayList v = new ArrayList();
  int i = 0;
  JButton
    b1 = new JButton("Button1"),
    b2 = new JButton("Button2");
  public DynamicEvents() {
    Container cp = getContentPane();
    cp.setLayout(new FlowLayout());
    b1.addActionListener(new B());
    b1.addActionListener(new B1());
    b2.addActionListener(new B());
    b2.addActionListener(new B2());
    cp.add(b1);
    cp.add(b2);
  }
  class B implements ActionListener {
    public void actionPerformed(ActionEvent e) {
      System.out.println("A button was pressed");
    }
  }
  class CountListener implements ActionListener {
    int index;
    public CountListener(int i) { index = i; }
    public void actionPerformed(ActionEvent e) {
      System.out.println(
        "Counted Listener " + index);
    }
  }
  class B1 implements ActionListener {
    public void actionPerformed(ActionEvent e) {
      System.out.println("Button 1 pressed");
      ActionListener a = new CountListener(i++);
      v.add(a);
      b2.addActionListener(a);
    }
  }
  class B2 implements ActionListener {
    public void actionPerformed(ActionEvent e) {
      System.out.println("Button2 pressed");
      int end = v.size() - 1;
      if(end >= 0) {
        b2.removeActionListener(
          (ActionListener)v.get(end));
        v.remove(end);
      }
    }
  }
  public static void main(String[] args) {
    JFrame frame = new DynamicEvents();
    frame.addWindowListener(
      new WindowAdapter() {
        public void windowClosing(WindowEvent e){
          System.exit(0);
        }
      });
    frame.setSize(300, 100);
    frame.setVisible(true);
  }
} ///:~