hw16_15.java

JAVA 2面向对象程序设计(习题参考答案9-17).rar

import java.awt.*;
import java.awt.event.*;
public class hw16_15 extends Frame implements KeyListener
{
   static hw16_15 frm=new hw16_15(); 
   static TextField txf=new TextField(18);
   static TextArea txa=new TextArea("",4,19,TextArea.SCROLLBARS_NONE);
   public static void main(String args[])
   {
      frm.setSize(200,150);
      frm.setTitle("Key Event");
      frm.setLayout(new FlowLayout(FlowLayout.CENTER));
      txf.addKeyListener(frm); 
      txa.setEditable(false);  
      frm.add(txf);      
      frm.add(txa);
      frm.setVisible(true); 
   }  
   public void keyPressed(KeyEvent e)
   {
      txa.setText("");     
      if(e.isActionKey())    
         txa.append("Action key is pressed\n");
      else                       
         txa.append(e.getKeyChar()+" is pressed\n");
   }
   public void keyReleased(KeyEvent e)  
   {
      txa.append("");
   }   
   public void keyTyped(KeyEvent e) 
   {
      txa.append("");
   }
}