Repainting a JPanel with data from another object (thread)

Repainting a JPanel with data from another object (thread)

I'm facing a problem where a JPanel takes data from an object which has a
cycle updating its state variables.
The scenario is as follows: a JFrame calls a method of the object, the
method creates the second JFrame has a cycle then updating a state
variable. The second JFrame access that variable and should be displayed
in a JPanel, but no, the GUI hangs.
I reduced the problem to an example with the same behavior so it can be
easily tested.
I appreciate any help, thanks!
Starter.java
public class Starter extends JFrame {
JButton button = new JButton("Fight!");
public Starter() {
button.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent arg0) {
OneClass.getInstance().start();
}
});
add(button);
}
public static void main(String[] args) {
Starter frame = new Starter();
frame.setTitle("Test");
frame.setSize(400, 300);
frame.setVisible(true);
}
}
OneClass.java
public class OneClass {
private OneFrame frame;
private int count;
private static OneClass instance;
private OneClass() {
}
public static OneClass getInstance() {
if (instance == null)
instance = new OneClass();
return instance;
}
public void start() {
frame = new OneFrame();
frame.setSize(400, 300);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
while (true)
{
count++;
System.out.println(count);
frame.repaint();
}
}
public int getCount() {
return count;
}
}
OneFrame.java
public class OneFrame extends JFrame {
private OnePanel panel = new OnePanel();
public OneFrame() {
setTitle("Test frame");
setContentPane(panel);
setResizable(false);
}
}
OnePanel.java
public class OnePanel extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
Font ft = new Font("Times New Roman", Font.PLAIN, 20);
g.setFont(ft);
g.drawString("Count = " + OneClass.getInstance().getCount(), 20, 20);
}
}