Re: How can I reset the text of button every second?

I want to set the button's text every second
as: 1 -> 2 -> 3 -> 4 .........
my code is:
------------------------------------
public class Ooop {
 public static void doIt() {
   JFrame jFrame = new JFrame();
   JButton jButton = new JButton("xxx");
   jFrame.add(jButton);
   jFrame.pack();
   jFrame.setVisible(true);

   int i=0;
   while(true){
     try {
       Thread.sleep(1000);
     }
     catch (InterruptedException ex) {
     }
     jButton.setText(String.valueOf(i++));
   }
 }
 public static void main(String[] args) {
   javax.swing.SwingUtilities.invokeLater(new Runnable() {
     public void run() {
       doIt();
     }
   });
 }
}
-------------------------------

I use Thread.sleep() to do it
but it can not work....
It show nothing all the time
just a blank frame, not button at all
why? is it about the Thread the UI using?