responsetokey.java

Java语言

import java.awt.*;
import java.applet.Applet;
import java.awt.event.*;
public class ResponseToKey extends Applet implements KeyListener{
	String keyName="";
	char ch;
	int code;
	Color clr;
	public void init(){
		addKeyListener(this);
		requestFocus();	
	}	
	public void paint(Graphics g){
		g.setColor(clr);
		g.drawString("健的名称："+KeyEvent.getKeyText(code),20,20);
		g.drawString("健代表的字符："+ch,20,40);
		g.drawString("健的编码值："+code,20,60);
		g.drawString("VK_UNDEFINED:"+KeyEvent.VK_UNDEFINED,20,80);
		g.drawString("CHAR_UNDEFINED:"+KeyEvent.CHAR_UNDEFINED,20,100);	
	}
	public void keyPressed(KeyEvent e){}
	public void keyReleased(KeyEvent e){
		ch=e.getKeyChar();
		code=e.getKeyCode();
		repaint();	
	}
	public void keyTyped(KeyEvent e){
		if(e.getKeyChar()=='r'||e.getKeyChar()=='R')
			clr=Color.red;
		else if(e.getKeyChar()=='g'||e.getKeyChar()=='G')
			clr=Color.green;
		else if(e.getKeyChar()=='b'||e.getKeyChar()=='B')
			clr=Color.blue;
		else
			clr=null;
		repaint();
	}
}