eleven1.java

java小程序

import   java.awt.*;   
  import   javax.swing.*;   
  import   java.awt.event.*;   
  //MyWindowListener;//   
    public   class   Eleven1   extends   JFrame   implements   ActionListener   
  {   
      private   Timer   t;   
      private   int   color=0;   
      private   Color[]   colors={Color.red,Color.green,Color.blue};   
        
      public   Eleven1()   
      {   
          super("ready");   
          t=new   Timer(500,this);   
          t.start();   
          setSize(500,80);   
          addWindowListener(new   WindowAdapter()   
              {   
                  public   void   windowClosing(WindowEvent   e)   
                  {   
                      t.stop();   
                      System.exit(0);   
                  }   
              });   
          show();   
      }   
      public   void   actionPerformed(ActionEvent   e)   
      {   
          color++;   
          if   (color>2)   color=0;   
          Graphics   g=getGraphics();   
          g.setColor(colors[color]);   
          g.drawLine(60,70,400,70);   
          g.dispose();   
      }   
      public   void   paint(Graphics   g)   
      {   
          Font   font=new   Font("Serif",Font.BOLD,20);   
          g.setFont(font);   
          g.drawString("按顺序变换水平线为红绿蓝色",60,60);   
          g.setColor(colors[0]);   
          g.drawLine(60,70,400,70);   
      }   
      public   static   void   main(String   args[])   
      {   
          Eleven1   app=new   Eleven1();   
      }   
  }