Animation

• java.awt.MediaTracker

LogoAnimator.java

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class LogoAnimator extends JPanel
                          implements ActionListener {
   protected ImageIcon images[];
   protected int totalImages = 30,
                 currentImage = 0,
                 animationDelay = 50; // 50 millisecond delay
   protected Timer animationTimer;

   public LogoAnimator()
   {
      setSize( getPreferredSize() );

      images = new ImageIcon[ totalImages ];
	  System.out.println("Loading images");

      for ( int i = 0; i < images.length; ++i ) { 
         images[ i ] =
            new ImageIcon( "images/deitel" + i + ".gif" );
		 System.out.print('.');
	  }
	  System.out.println("\nDone");

      startAnimation();
   }

   public void paintComponent( Graphics g )
   {
      super.paintComponent( g );

      if ( images[ currentImage ].getImageLoadStatus() ==
           MediaTracker.COMPLETE ) {
         images[ currentImage ].paintIcon( this, g, 0, 0 );
         currentImage = ( currentImage + 1 ) % totalImages;
      }
   }

   public void actionPerformed( ActionEvent e )
   {
      repaint();
   }

   public void startAnimation()
   {
      if ( animationTimer == null ) {
         currentImage = 0;  
         animationTimer = new Timer( animationDelay, this );
         animationTimer.start();
      }
      else  // continue from last image displayed
         if ( ! animationTimer.isRunning() )
            animationTimer.restart();
   }

   public void stopAnimation()
   {
      animationTimer.stop();
   }

   public Dimension getMinimumSize()
   { 
      return getPreferredSize(); 
   }

   public Dimension getPreferredSize()
   {
      return new Dimension( 160, 80 );
   }

   public static void main( String args[] )
   {
      LogoAnimator anim = new LogoAnimator();

      JFrame app = new JFrame( "Animator test" );
      app.getContentPane().add( anim, BorderLayout.CENTER );

      app.addWindowListener(
         new WindowAdapter() {
            public void windowClosing( WindowEvent e )
            {
               System.exit( 0 );
            }
         }
      );

      // The constants 10 and 30 are used below to size the
      // window 10 pixels wider than the animation and
      // 30 pixels taller than the animation. 
      app.setSize( anim.getPreferredSize().width + 10,
                   anim.getPreferredSize().height + 30 );
	  app.setVisible(true);
   }
}

Maintained by John Loomis, last updated 19 July 2000