Thread: Rectangles

I'm not sure why this program doesn't make a moving rectangle:

public static void main(String[] args)
{
 
    import java.awt.*;
    import javax.swing.*;
 
    public class Advertisement extends JApplet implements Runnable
    {
        Thread animator;
        int yPosition;
 
        public void init()
        {
            JRootPane rootPane = this.getRootPane();
            rootPane.putClientProperty("defeatSystemEventQueueCheck",
                Boolean.TRUE);
        }
 
        public void start()
        {
            xPosition = 0;
            yPosition = 0;
            animator = new Thread(this);
            animator.start();
        }
        public void paint(Graphics g)
        {
            g.setColor(Color.cyan);
            g.fillRect(0, 0, getWidth(), getHeight());
            g.setColor(Color.red);
            g.fillRect(xPosition, yPosition, 100, 100);
 
        }
 
        public void run()
        {
            while (Thread.currentThread() == animator)
            {
                xPosition = xPosition +1;                
                yPosition = yPosition +1;
                repaint();
 
                if (yPosition >350)
                {
                    yPosition = 50;
                }
                if (xPosition >350)
                {
                    xPosition = 50;
                }
               try
               {
                   Thread.sleep(10);
                }
                catch (InterruptedException e)
                {
                    break;
                }
            }
        }
 
    public void stop()
    {
        animator = null;
    }
}
}

You update some position variables, but you never repaint so those new position variables are never used.

That worked. Thanks.

You're welcome.