event12_6.java

很有用的课件

 /**
  * ClassName: Event12_6.class
  * Description:
  * Copyright:    Copyright (c) 2002
  * Company: 中国青年出版社
  * @author: Hong Yi
  * @version 1.0
  */

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

class MyKeyListener implements KeyListener
{

    public void keyPressed(KeyEvent evt)
    {
       System.out.println("\n按键被按下");
       showKeyEventMsg(evt);
    }

	public void keyReleased(KeyEvent evt)
	{
	}

	public void keyTyped(KeyEvent evt)
	{
	}

	private void showKeyEventMsg(KeyEvent evt)
        //显示按键事件信息
	{

        //得到按键对应的整型数
		int code = evt.getKeyCode();
		//返回按键事件所代表的字符
		char c = evt.getKeyChar();

		//得到代表按键的字符串
		String szText = evt.getKeyText(code);

		if (code != KeyEvent.VK_UNDEFINED)
			System.out.println("\n按键对应的整型数："+code);

		if (c != KeyEvent.CHAR_UNDEFINED)
			System.out.println("\n与按键相联系的字符："+c);

		if (evt.isShiftDown())
			System.out.println("\n按键Shift被按下");

		System.out.println("\n按键本身的字符串："+szText);
	}
}

class ButtonPanel extends JPanel
//声明ButtonPanel类为监听器类，实现ActionListener接口
{
    public ButtonPanel()
    {
	    //新建一个文本域组件
        tf = new JTextField(20);
	   add(tf);
	   //指定用来处理该按钮事件的监听器对象为JPanel本身
	   myListener = new MyKeyListener();
	   tf.addKeyListener(myListener);
    }
    private JTextField tf;
    private MyKeyListener myListener;
}

class ButtonFrame extends JFrame
{
	public ButtonFrame()
    {
	    //设置窗口MyFrame的标题
	    setTitle("事件示例程序12.6");
	    //设置窗口大小为宽300，高200象素
        setSize(300, 200);
        //通过设置窗口作上角坐标为（100，100）来设置窗口位置
        setLocation(100,100);

        //增加窗口事件监听器
        addWindowListener(new WindowAdapter()
        {
		    public void windowClosing(WindowEvent e)
            {  System.exit(0);
             }
        });

	    //得到当前窗口的内容窗口
        Container ctPane = getContentPane();
        //在内容面板中绘制自己定义的面板MyPanel
        ctPane.add(new ButtonPanel());
   }
}

public class Event12_6
{
   public static void main(String[] args)
   {
	  JFrame frame = new ButtonFrame();
      frame.setVisible(true);
   }
}