Swing Timer in main class doesn't repaint JFrame class

I have a main class that holds a Array List of objects and has a Swing timer that repaints a separate JFrame Class. Despite the repaint method being called, the screen isn't being updated.

What's supposed to happen: When any key is pressed, the x location of two objects are updated. A swing timer that ticks every half second calls the repaint method. The images are then redrawn in their updated locations.

From what I can tell the location of the images are being updated, as when I minimize and reopen the JFrame window, the images have moved.

I've tried changing the intervals at which the timer runs, moving the swing timer to the JFrame class, putting the repaint(); in a thread. However I still don't know why repaint(); isn't updating the screen.

Here's a sketch of my code: JFrame class

public class testingGround extends JPanel { private Image image; private qwq getter = new qwq(); protected Keyboard keyboard = new Keyboard(); //KeyListener, imported from Keyboard class private JFrame frame = new JFrame(); //JFrame variable public void createGUI(){ testingGround panel = new testingGround(); // Creating a new JPanel, for objects to be drawn on JFrame frame = new JFrame("Game"); //Creating a new JFrame called frame frame.setSize(600, 600); //Setting the size of the JFrame frame to be 600x600 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);// Setting so the frame exits on close frame.setVisible(true); frame.add(panel);// Adding the JPanel panel to the JFrame frame, so it's visible frame.addKeyListener(keyboard); //Adding a KeyListener to detect users input in the JFrame frame } public Frame getFrame() { //Constructor class to get JFrame in other classes return frame; } public void initComponents(){ ImageIcon imageIcon = new ImageIcon("C:/Users/destr/workspace/GameWIP3/bin/A2.png"); image =imageIcon.getImage(); } protected void paintComponent (Graphics g){//Drawing super.paintComponent(g); initComponents(); for (int i=0;i<getter.getFListSize();i++) { System.out.print("paint called"); g.drawImage(image, getter.getFighter(i).getFighterX(), getter.getFighter(i).getFighterY(), null); } } } 

Keyboard Class

public class Keyboard implements KeyListener { private qwq getter = new qwq(); @Override public void keyPressed(KeyEvent e) { getter.getFighter(0).setFighterX(500);; getter.getFighter(1).setFighterX(200);; System.out.print("Updated the x value of two"); } 

Main Class

public class qwq implements ActionListener { private static ArrayList<Fighter> FighterList = new ArrayList<Fighter>(); // ArrayList // of // Fighters Timer timer = new Timer(500, this); private static testingGround GUI = new testingGround(); public qwq() { timer.start(); } public Fighter getFighter(int i) { return FighterList.get(i); // To retrieve a fighter from the Array List } public void addFighter(Fighter i) { FighterList.add(i); // To add a fighter to the Array list } public int getFListSize() { return FighterList.size(); } public static void main(String[] args) { GUI.createGUI(); GUI.getFrame(); FighterList.add(new Fighter(0, 0)); FighterList.add(new Fighter(20, 50)); } @Override public void actionPerformed(ActionEvent e) { if (e.getSource() == timer) { GUI.repaint(); } } } 

Object Class

public class Fighter { private int fighterX; private int fighterY; public Fighter ( int fighterX, int fighterY) { this.setFighterX(fighterX); this.setFighterY (fighterY); } public int getFighterX (){ return fighterX; //method to get x coordinate of a fighter } public int getFighterY (){ return fighterY;//method to get y coordinate of a fighter } public void setFighterX(int fighterX) { this.fighterX = fighterX; //method to set the x coordinate of a fighter } public void setFighterY(int fighterY) { this.fighterY = fighterY; //method to set the y coordinate of a fighter } }