An animation is created on mobile by calling the repaint() method of Canvas class.T he image is displayed on screen at regular intervals with different positions to bring the effect of animation.

Illustration below displays animation for few seconds, then displays a static text.

 import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

public class Animation extends MIDlet implements CommandListener
{
  public Display display;
  public Animation() {}

  public void startApp() 
  {
    AnimationCanvas animation=new AnimationCanvas(this);
    animation.startAnimation();
    Display.getDisplay(this).setCurrent(animation);
  }

  public void pauseApp() {}

  public void destroyApp( boolean unconditional ) {}

  public void exit()
  {
    destroyApp(true);
    notifyDestroyed();
  }

  public void commandAction(Command c, Displayable s){}
}


import javax.microedition.lcdui.*;

public class AnimationCanvas extends Canvas implements Runnable, 
 CommandListener
{
  private Animation midlet;
  int height;
  int width;
  int pad = 3;
  boolean finishedAnimation = false;
  int deltaY = 0;

  private Command  startCommand;
  private Command exitCommand;
  private Command aboutCommand;


  public AnimationCanvas(Animation midlet)
  {
    this.midlet=midlet;
    height = getHeight();
    width = getWidth();

    startCommand = new Command("Start",Command.BACK,1);
    exitCommand = new Command("Exit",Command.SCREEN,0);
    aboutCommand = new Command("About",Command.SCREEN,3);
  }

  public void paint(Graphics g)
  {
    g.setColor(0xFFFFFF);
    g.fillRect(0,0,width,height);
    g.setColor(0,255,0);
    g.drawRoundRect(0,0,width-1,height-1,10,10);
  
    if (finishedAnimation)
    {
      Form form = new Form("Animation");
      form.append("Animation Complete\n");
      form.addCommand(exitCommand);
      form.setCommandListener(this);
      Display.getDisplay(midlet).setCurrent(form);

    }
    else
    {
      Image img=null;
      try 
      {
        img = Image.createImage("/logo.png");
      }
      catch(Exception e){}
      int ih = img.getHeight();
      int iw = img.getWidth();
      int imgX = (width-2)/2;
      int imgY = (height-2)/2;
      g.drawImage(img,imgX,imgY+deltaY,Graphics.VCENTER|Graphics.HCENTER);
        
      removeCommand(exitCommand);
    }
  }

  public void startAnimation()
  {
    try
    {
      finishedAnimation = false;
      Thread t = new Thread(this);
      t.start();
    }
    catch(Exception e){}
  }

  public void run()
  {
    try
    {
      int count = 0;
      int sleep_time = 200;
      while (true)
      {
        Thread.sleep(sleep_time);
        count++;
        if (count > 20) 
        {
          finishedAnimation = true;
          Thread.sleep(sleep_time);
          repaint();
          break;
        }
        if (count <=5 ) 
          deltaY += 5;
        else if (count >5 && count <=15)
          deltaY -= 5;
        else 
          deltaY +=5;
        repaint();
      }
    }
    catch(Exception e){}
  }

  public void commandAction(Command c,Displayable d)
  {
    if (c == exitCommand){
      midlet.exit();}
  }
}

 

 

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