Changing the color of frame background repeatedly

Question

So i want my methods to change the background color of my Frame every like 0.2 seconds and i tried a lot of diferent things like new methods and Threat sleep/wait but nothing worked even though trying it with System.out.print did. I have no idea what could work now so would be ice if someone helped me out, thank you beforehand!

PS.: dont mind the variable and method names was having fun with my friends xD

public void poggersModeOn()
{
    f.setTitle("Insane rainbow pogg mode!!!!1!!!11!!1!! ");
    int rot = (int)(Math.random()*255+1);
    int gruen = (int)(Math.random()*255+1);
    int blau = (int)(Math.random()*255+1);
    f.setBackground(new Color(rot, gruen, blau));
}

public void poggersModeOff()
{
    f.setTitle("Navigationssystem");
    f.setBackground(new Color(255, 255, 255));
}

public void pogmethode() {
    while(pogmode==true)
    {
        poggersModeOn();
        //wait function right here
    }
}

Answer 1

Assuming your using Swing, then you should use a Swing Timer, see How to Use Swing Timers

import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;

public class Main {
    public static void main(String[] args) {
        new Main();
    }

    public Main() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                JFrame frame = new JFrame();
                frame.add(new TestPane());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TestPane extends JPanel {

        public TestPane() {
            Timer timer = new Timer(250, new ActionListener() {
                private Random rnd = new Random();
                @Override
                public void actionPerformed(ActionEvent e) {
                    int red = rnd.nextInt(255);
                    int green = rnd.nextInt(255);
                    int blue = rnd.nextInt(255);
                    setBackground(new Color(red, green, blue));
                }
            });
            timer.start();
        }

        @Override
        public Dimension getPreferredSize() {
            return new Dimension(400, 400);
        }
    }
}

Why? Because Swing is single threaded (and not thread safe). See Concurrency in Swing for more details