Java Key Bindings not working / actionPerformed is not called

You are using the wrong InputMap. Use getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW)

. This way you will bind to keys that are active when the JPanel has no focus, but is displayed in the window it does. By default, InputMap is used for JComponent.WHEN_FOCUSED

, which is only valid if the associated component has focus, which you don't want or use.

this.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke("A"), 
        "moveLeft");

      

        
        
        
      

    

Also use classes that extend AbstractAction rather than those that implement Action, since your actions are not fully connected. And yes, you can redraw at the end of the actionPerformed as long as you have a link to a JPanel that ActionEvent can help you with.

Testing program:

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.image.BufferedImage;

import javax.swing.AbstractAction;
import javax.swing.ImageIcon;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.KeyStroke;

public class Window {

   public Window() {
      JFrame frame = new JFrame("Epic Game");
      frame.setSize(800, 600);
      frame.setLocationRelativeTo(null);
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

      GamePanel panel = new GamePanel();
      frame.add(panel);

      frame.setVisible(true);

      // !! while (true) {
      // panel.repaint();
      // }
   }

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

@SuppressWarnings("serial")
class GamePanel extends JPanel {
   int nameSwap = 0;
   Player player;

   public GamePanel() {
      player = Player.getInstance();
      repaint();
      System.out.println("Repaint method called");

      this.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke("A"), "moveLeft");
      this.getActionMap().put("moveLeft", new MoveLR(-1));

      this.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke("D"), "moveRight");
      this.getActionMap().put("moveRight", new MoveLR(1));

      this.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke("S"), "fire");
      this.getActionMap().put("fire", new Fire());
   }

   public void paintComponent(Graphics g) {
      super.paintComponent(g);
      g.drawImage(player.getImg().getImage(), player.getX(), player.getY(), 50,
            50, null);
      // System.out.println("Graphics method called");
   }
}

class Player {
   private int xLoc, yLoc;
   private boolean isFiring;
   private String filename;
   private ImageIcon imageicon;
   // !! private URL imgURL;

   private static Player player;

   public Player(int xl, int yl, boolean fire, String name) {
      BufferedImage img = new BufferedImage(20, 20, BufferedImage.TYPE_INT_ARGB);
      Graphics2D g2 = img.createGraphics();
      g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
            RenderingHints.VALUE_ANTIALIAS_ON);
      g2.setColor(Color.red);
      g2.fillOval(2, 2, 16, 16);
      g2.dispose();
      imageicon = new ImageIcon(img);
      xLoc = xl;
      yLoc = yl;
      isFiring = fire;
      filename = name;
      // !! imgURL = getClass().getResource(name);
      // imageicon = new ImageIcon(imgURL);
   }

   public static Player getInstance() {
      if (player == null) {
         player = new Player(0, 0, false, "Dog.jpg");
      }
      return player;
   }

   public void fire() {

   }

   public int getX() {
      return xLoc;
   }

   public int getY() {
      return yLoc;
   }

   public void newX(int x) {
      xLoc = x;
   }

   public ImageIcon getImg() {
      return imageicon;
   }

   public void newImg(ImageIcon ii) {
      imageicon = ii;
   }

   // !! public URL getURL(){
   // return imgURL;
   // }
   // !! public void newURL(String n){
   // imgURL = getClass().getResource(n);
   // }
   public void updateObject() {
      // !! imageicon = new ImageIcon(imgURL);
      System.out.println("update object called");
   }
}

class MoveLR extends AbstractAction {
   private int moveVal;
   Player player;

   public MoveLR(int mv) {
      moveVal = mv;
      player = Player.getInstance();
      System.out.println("New MoveLR object made");
   }

   @Override
   public void actionPerformed(ActionEvent e) {
      // TODO Auto-generated method stub
      player.newX(player.getX() + moveVal);
      ((JPanel) e.getSource()).repaint();
      System.out.println("actionPerformed() called");
   }

}

class Fire extends AbstractAction {
   public Fire() {
      System.out.println("Fire created");
   }

   @Override
   public void actionPerformed(ActionEvent arg0) {
      System.out.println("Fire called");
   }
}