setVisible() problem after button click

Hello,

I am having a big problem with the setVisible() method. It seems not
to work when an event such as a button click is involved in calling
it.

///// Pseudocode /////
display_messeges() {
loop {
add components to JFrame....
setVisible(true);
Sleep for a few seconds
}
}

The confusing thing is this will work when called from main, but does
not update the screen when called from actionPerformed method.

Am I doing somthing stupid here?...... it is driving me crazy
the test code is below...
Thanks
Sam

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.util.Random;

public class set_visible_test extends JFrame implements ActionListener
{

    private static set_visible_test demo;
    private JLabel test_label;
    private JButton button;
    private JPanel test_panel;
    Container window;
    private int button_pressed=0;

    public static void main(String[] args) {
        demo = new set_visible_test();
        demo.setSize(500,500);
        demo.createGUI();
    }

private void createGUI() {

    // CREATE AND ADD A BUTTON TO THE FRAME
        if (button_pressed ==0){
         setDefaultCloseOperation(EXIT_ON_CLOSE);
            window = getContentPane();
            window.setLayout(new BoxLayout(window, BoxLayout.PAGE_AXIS));

            test_panel = new JPanel(new FlowLayout());

            button = new JButton("CLICK HERE");

            button.addActionListener(this);
            test_panel.add(button);
            window.add(test_panel);
            demo.setVisible(true);

        }
        else {

////// WHEN THE BUTTON IS CLICKED DISPLAY A MESSEGE
////// AND SLEEP FOR 5 SECONDS
////// THEN DISPLAY SECOND MESSEGE
        System.out.println("button clicked");
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        window = getContentPane();
        window.setLayout(new BoxLayout(window, BoxLayout.PAGE_AXIS));

        test_panel = new JPanel(new FlowLayout());

        test_label = new JLabel("FIRST STAGE");
        test_panel.add(test_label);
        window.add(test_panel);

       demo.setVisible(true);
       /////////////////// this setVisible(true) command is not
working !!!!!!!!!!!!!!!

        try {Thread.sleep(5000);} catch (InterruptedException e){}

        setDefaultCloseOperation(EXIT_ON_CLOSE);
        window.removeAll();
        window = getContentPane();
        window.setLayout(new BoxLayout(window, BoxLayout.PAGE_AXIS));

        test_panel = new JPanel(new FlowLayout());
        test_label = new JLabel("SECOND STAGE");
        test_panel.add(test_label);
        window.add(test_panel);
        demo.setVisible(true);
        }

        }

public void actionPerformed(ActionEvent event) {
    button_pressed=1;
    demo.createGUI();

}
}