How to expand an oval in an animation?

Question

I am taking a beginner Java online course and am at the 2nd to last lesson and I am having a hard time figuring out the following assignment and have only gotten the oval to move across the screen not to expand. Any suggestions or tips with the following are appreciated.
Assignment instructions:
Create an applet named GoOval that draws a gradually- growing, small blue oval. Increase the width of the oval by perhaps one pixel every fifth of a second or so.
If you'd like, you can try increasing the height of the oval by one pixel at the same time its width is increasing by one pixel. Don't create another loop--you should be able to increase the width in the exact same loop that you are using to increase the height.
If you'd like a real challenge, try to make the oval move around in the applet window as it grows (perhaps by allowing the oval's x or y position to change in the same loop you are using to change the oval's width and height).
No need to send me your applet, but please post a message within the Discussion Area if you have any difficulties.
What I did so far:
import java.awt.*;
public class GoOval extends java.applet.Applet implements Runnable
int pos=10;
Thread animator;
public void start()
animator = new Thread(this);
animator.start();
public void stop()
animator = null;
} public void paint(Graphics g)
g.setColor(Color.blue);
     g.fillOval(pos,10,10,10);
public void run()
{        while (Thread.currentThread() == animator)
pos=pos+10;
repaint();
try
Thread.sleep(100);
catch (InterruptedException e)
break;
if (pos >= 300)
pos=10;
     

Answer 1

You about had it, just added three more variables; maybe yo only wanted two for size and not height:
/*<applet code=GoOval.class width=400 height=300></applet>*/
import java.awt.*;
public class GoOval extends java.applet.Applet implements Runnable {
  int pos=10, posy=10, wdth=10, hght=10; // Added three more variables
  Thread animator;
  public void start() {
    animator = new Thread(this);
    animator.start();
  public void stop() {
    animator = null;
  public void paint(Graphics g)  {
    g.setColor(Color.blue);
    g.fillOval(pos,posy,wdth,hght); // Chgd
  public void run() {
    while (Thread.currentThread() == animator)  {
      pos+=10;
      posy+=10; // added
      wdth+=10; // added
      hght+=10; // added
      repaint();
      try {
        Thread.sleep(100);
      catch (InterruptedException e) {
        break;
      if (pos >= 300) {
        pos=10;
        posy=10; // added
        wdth=10; // added
        hght=10; // added
}~Bill