typewriter.java

来自「java 完全探索的随书源码」· Java 代码 · 共 56 行

// TypeWriter.java

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

public class TypeWriter extends Applet implements Runnable
{
   Thread t;
   String text = "Java makes typing fun!";

   int index;
   final int len = text.length ();

   public void start ()
   {
      if (t == null)
      {
          t = new Thread (this);
          t.start ();
      }
   }

   public void stop ()
   {
     t = null;
   }

   public void run ()
   {
      Thread current = Thread.currentThread ();

      while (t == current)
      {
         try
         {
            Thread.sleep (200);
         }
         catch (InterruptedException e) {}

         repaint ();

         index++;
         if (index >= len)
             index = 0;
      }
   }
  
   public void paint (Graphics g)
   {
      g.setColor (Color.blue);

      String s = text.substring (0, index + 1);
      g.drawString (s, 10, 30);
   }
}