Change JButton Color in a Thread

Change JButton Color in a Thread

I am trying to make a game like simon:
http://www.freegames.ws/games/kidsgames/simon/simon.htm#
I am making a smaller scale with only 2 buttons. I want the color to
switch between 2 buttons, button1 and button2. This is in a thread because
I need buttons to be clicked while this is happening. When I open the
program the button color stays as-is.
Thanks for help in advance!
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.FlowLayout;
import javax.swing.*;
public class TestFrame extends JFrame{
public JButton button1;
public JButton button2;
boolean isTrue = true;
boolean switchColor = true;
TestFrame(){
super("Simon");
initialize();
this.setSize(200, 400);
this.setVisible(true);
}
private void initialize() {
this.setLayout(new BorderLayout());
button1 = new JButton();
button1.setBackground(Color.green);
button1.setSize(200,200);
button2 = new JButton();
button2.setSize(200, 200);
button2.setBackground(Color.blue);
this.add(button1, BorderLayout.NORTH);
this.add(button2, BorderLayout.SOUTH);
Thread t = new Thread(r1);
t.start();
}
Runnable r1 = new Runnable() {
public void run() {
while(isTrue){
if(switchColor = true){
button1.setBackground(Color.blue);
button2.setBackground(Color.green);
try {
Thread.sleep(500);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
refresh();
switchColor = false;
} else {
button1.setBackground(Color.green);
button2.setBackground(Color.blue);
try {
Thread.sleep(500);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
refresh();
switchColor = true;
}
}
}
};
public void refresh(){
this.invalidate();
this.validate();
this.repaint();
}
}