Java Animation Problems

[TheWeakGetEaten]

I am trying to get a simple program to work were a image moves across the window. When my program gets to the void hop(int iStart, int iStop) method, repaint does not invoke a new paint. So all I get is a blank screen. How can I get repaint to place my image in the window?

import java.applet.*;
import java.awt.*;
import java.awt.event.*;


public class Main extends Applet implements ActionListener{
	Animate animate;
	Button fire;
	public void init()
	{
		this.setBackground(Color.white);
		fire = new Button("Fire!");
		add(fire);
		fire.addActionListener(this);
	}

	@Override
	public void actionPerformed(ActionEvent arg0) {
		animate = new Animate();
	}
}

//*******************************************

import java.awt.*;
import java.io.*;
import javax.imageio.*;


public class Animate extends Panel implements Runnable{

    Thread threadBananaAnimation = new Thread(this);
	Image img;
    int xPosition = 0;
    int yPosition = 50;
    int iStart = 0;
    int iStop = 300;
	public Animate()
	{
	    try
	    {
	       File file = new File("c:/banana.gif");
	       img = ImageIO.read(file);
	    }catch (Exception e)
	    {
	    	System.out.print("Could not find image file!");
	    }	    
	    threadBananaAnimation.start();
	}

	public void run()
    {
          while (true)
         {
              hop( 0, 300);
              repaint();
              try { Thread.sleep( 500 ); }
              catch (InterruptedException e) { }

              hop( 300, 600);
              hop( 600, 300);

              repaint();
              try { Thread.sleep( 500 ); }
              catch (InterruptedException e) { };
              
              hop( 300, 0);
         }
    }	
	 void hop(int iStart, int iStop)
     {
          boolean bGround = true;

          System.out.print("This is a test");
          //*****The program is running through this for loop
          //*****but will not repaint my image
          for (int i = iStart; i < iStop; i += 10)
          {
               xPosition = Math.abs(i);

               if (bGround)
               {
                    yPosition = 50;
                    bGround = false;
               }
               else
               {
                    yPosition = 40;
                    bGround = true;
               }
               try { Thread.sleep( 500 ); }
               catch (InterruptedException e) { }
               repaint();
          }
     }	

	public void paintComponent(Graphics g)
	{
		super.paintComponents(g);
        
        g.drawImage(img, xPosition, yPosition, getParent());
	}
}

Thanks in advance for your help!!