Using Timer To Pause Program Execution [duplicate]

Answer 1

So instead of...

while(rad < 200){
    repaint();
    rad++;
    try {
        Thread.sleep(100);
    } catch (InterruptedException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

You simply need to turn the logic around a little...

Timer timer = new Timer(1000, new ActionListener() {
    public void actionPerformed(ActionEvent evt) {
        rad++;
        if (rad < 200) {
            repaint();
        } else {
            ((Timer)evt.getSource()).stop();
        }
    }
});
timer.start();

Basically, the Timer will act as the Thread.sleep(), but in a nice way that doesn't break the UI, but will allow you to inject a delay between execution. Each time it executes, you need to increment your value, test for the "stop" condition and update otherwise...

Take a look at How to Use Swing Timers and the other 3, 800 questions on the subject on SO...