我画的这个圆为什么不动import java.awt.Color;import java.awt.Graphics;im

我画的这个圆为什么不动
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Panel;
public class GamePanel extends Panel{
private int x;
private int y;
private int zhijing;
public GamePanel(){
x=50;
y=50;
zhijing=100;
}
public void paint(Graphics g){
g.setColor(Color.BLUE);
g.fillOval(x,y,zhijing,zhijing);
}
public void gameLoop(){
while(true){
x++;
for(int i=1;i