Java Tutorial/2D Graphics/Animation

Color fading animation

   <source lang="java">

import java.awt.AlphaComposite; import java.awt.Color; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.RenderingHints; import java.awt.geom.Rectangle2D; import javax.swing.JFrame; import javax.swing.JPanel; public class ColorFadingAnimation extends JPanel {

 private Rectangle2D rect = new Rectangle2D.Float(20f, 20f, 80f, 50f);
 private float alpha_rectangle = 1f;
 public ColorFadingAnimation() {
   new RectRunnable();
 }
 public void paint(Graphics g) {
   super.paint(g);
   Graphics2D g2d = (Graphics2D) g;
   g2d.setColor(new Color(50, 50, 50));
   RenderingHints rh = new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
   rh.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
   g2d.setRenderingHints(rh);
   g2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, alpha_rectangle));
   g2d.fill(rect);
 }
 public static void main(String[] args) {
   JFrame frame = new JFrame("Color fading aniamtion");
   frame.add(new ColorFadingAnimation());
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   frame.setSize(250, 150);
   frame.setLocationRelativeTo(null);
   frame.setVisible(true);
 }
 class RectRunnable implements Runnable {
   private Thread runner;
   public RectRunnable() {
     runner = new Thread(this);
     runner.start();
   }
   public void run() {
     while (alpha_rectangle >= 0) {
       repaint();
       alpha_rectangle += -0.01f;
       if (alpha_rectangle < 0) {
         alpha_rectangle = 0;
       }
       try {
         Thread.sleep(50);
       } catch (Exception e) {
       }
     }
   }
 }

}</source>