multilistener.java~19~

来自「提供了常用的JAVA技术的示例」· JAVA~19~ 代码 · 共 69 行

package MultiListener;

import java.awt.*;
import java.awt.event.*;
import java.util.*;

public class MultiListener implements ActionListener,ItemListener,WindowListener{
    private Frame f;
    private java.awt.List lst;
    private TextField tf;
    static Random num=new Random(1000);

    public void create() {
        f = new Frame("testing the listing");
        tf=new TextField();

        lst=new java.awt.List(4,false);
        lst.add("1");
        lst.add("2");
        lst.add("3");
        lst.add("4");
        lst.addItemListener(this);
        lst.addActionListener(this);

        f.setSize(300,300);
        f.add(lst,"Center");
        f.add(tf,"South");
        f.addWindowListener(this);
        f.setVisible(true);

    }
    public void itemStateChanged(ItemEvent e){
        int id=((java.awt.List)e.getSource()).getSelectedIndex();
        switch(id){
            case 0:{tf.setText("id-1 is :"+num.nextInt());
                    tf.setBackground(new Color(225,230,0));
                    break;
                    }
            case 1:{tf.setText("id-2 is :"+num.nextInt());
                    break;
                    }
            case 2:{tf.setText("id-3 is :"+num.nextInt());
                    break;
                    }
            case 3:{tf.setText("id-4 is :"+num.nextInt());
                    break;
                    }
        }
    }
   public void actionPerformed(ActionEvent e){
      /*  tf.setForeground(Color.blue);
        tf.setBackground(new Color(225,230,0));
        lst.setBackground(new Color(225,230,0));
        lst.setForeground(new Color(0,0,255));*/
    }

   // public void windowClosing(WindowEvent e){System.exit(1);}
    public void windowActivated(WindowEvent e){}
    public void windowClosed(WindowEvent e){}
    public void windowDeactivated(WindowEvent e){}
    public void windowDeiconified(WindowEvent e){}
    public void windowIconified(WindowEvent e){}
    public void windowOpened(WindowEvent e){}

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