multilistener.java

来自「java的书上例子」· Java 代码 · 共 68 行

//例12_10	 实现了多个接口的例子
import java.awt.*;
import java.awt.event.*;
import java.util.*;

public class MultiListener implements ActionListener, ItemListener, WindowListener     //实现了多个接口
{
	private Frame f;
	private java.awt.List lst;  
//java.awt和java.util包都有list类，所以要具体指明
    private TextField tf;
    static Random num = new Random(1000);

	public void create() {
	f = new Frame("example for testing the listeners ");
    tf = new TextField();				
	lst = new java.awt.List(4, false);
    lst.add("Hao JianWen");
    lst.add("Gu ZhiFeng");
    lst.add("Zou Tao");
    lst.add("Ma Lu");
    lst.addItemListener(this);     //注册监听器接口ItemListener
    lst.addActionListener(this);   //注册监听器接口ActionListener  
 	f.add(lst,"Center");
    f.add(tf,"South");                   
	f.addWindowListener(this);     //注册监听器接口WindowListener
	f.setSize(300,200);
	f.setVisible(true);		
}

   public void itemStateChanged(ItemEvent e){
   int id = ((java.awt.List)e.getSource()).getSelectedIndex();
   switch(id){
        case 0:{ tf.setText("Hao JianWen's ID is: "+ num.nextInt());
                 break;
                }
        case 1:{tf.setText("Gu ZhiFeng's ID is: "+num.nextInt());
                 break;
                }
        case 2:{tf.setText("Zou Tao's ID is: "+num.nextInt());
                 break;
                }
        case 3:{tf.setText("Ma Lu's ID is: "+num.nextInt());
                 break;
                }
             }
     }	
  public void actionPerformed(ActionEvent e){
     tf.setForeground(new Color(225,0,230));
    }

    public void windowClosing(WindowEvent e) {  
	             System.exit(1);
   //为了使窗口能正常关闭，程序正常退出，需重写windowClosing方法
		}
   public void windowOpened(WindowEvent e) {}
   public void windowIconified(WindowEvent e) {}
   public void windowDeiconified(WindowEvent e) {}
   public void windowClosed(WindowEvent e) {}
   public void windowActivated(WindowEvent e) {}
   public void windowDeactivated(WindowEvent e) {}

   public static void main(String args[])
	{
		MultiListener ml = new MultiListener();
		ml.create();     }
	}