functionkeys.java

来自「java网络高级编程的配套源码,java网络高级编程为清华出版社出版.」· Java 代码 · 共 41 行

/*源程序清单4-15*/

import java.awt.*;
import java.applet.*;

public class FunctionKeys extends Applet
  {
    String KeyDownEvent = null;
    String KeyUpEvent = null; 

    public boolean keyUp(Event event, int letter)
     {
       if(event.id == Event.KEY_ACTION)
       KeyUpEvent = "Function key released";
       else if (letter == 27)//Esc键
       KeyUpEvent = "Esc key released";
     else
       KeyUpEvent = "KeyUp："+(char)letter;
     repaint();
     return(true); 
    }

  public boolean keyDown(Event event,int letter)
    {
     if(event.id == Event.KEY_ACTION)
       KeyDownEvent = "Function key pressed";
     else if(letter ==27)//ESC键
       KeyDownEvent="KeyDown："+(char)letter;
     repaint();
     return(true);
    }

  public void paint(Graphics g)
    {
     if (KeyUpEvent!= null)
      g.drawString(KeyUpEvent,5,45); 
     if(KeyDownEvent!= null)
      g.drawString(KeyDownEvent,5,75);
    }
  }