How move sprite in Java 2d (swing) with keyboard?

Question

I'm practicing some simple techniques with Java swing games, to learn the basics. Right now I'm practicing how to move a sprite... but it's not working! whhyyyy

Here is what I've come up with so far (Main class):

public class GraphicsPracticeDrawing extends JPanel implements Runnable{

private CoinSprite coin2;
private Thread animate;

private final int DELAY = 25;

public GraphicsPracticeDrawing(){
    setBackground(Color.BLACK);
    this.addKeyListener(new InputHandler());

    Initialize();
    animate = new Thread(this);
    animate.start();
}

public void Initialize(){
    coin2 = new CoinSprite("images/coin.gif", 25, 25);
}

public void paintComponent(Graphics g){
    super.paintComponent(g);

    Graphics2D g2d = (Graphics2D)g;
    g2d.drawImage(coin2.getImage(), coin2.getX(), coin2.getY(), null);
}

@Override
public void run() {
    long beforeTime, timeDiff, sleep;

    beforeTime = System.currentTimeMillis();

    while(true){
        coin2.move2(); //move the 2nd coin based on the inputHandler
        repaint();

        timeDiff = System.currentTimeMillis() - beforeTime;
        sleep = DELAY - timeDiff;

        if(sleep < 0)
            sleep = 2;

        try{
            Thread.sleep(sleep);
        } catch(InterruptedException e){
            System.out.println("Animation interrupted!");
        }

        beforeTime = System.currentTimeMillis();
    }
}

/*
 * create a inner class to handle key inputs via the CoinSprite class
 */
private class InputHandler extends KeyAdapter{
    public void keyPressed(KeyEvent e) {
        coin2.keyPressed(e);
    }
    public void keyReleased(KeyEvent e) {
        coin2.keyReleased(e);
    }
}

}

and for my CoinSprite class:

public class CoinSprite {

private BufferedImage img;
private int speedKeyX, speedKeyY;

public CoinSprite(){ }

public CoinSprite(String fileLoc, int x, int y){
    try{
        this.img = ImageIO.read(new File(fileLoc));
    } catch (IOException e){
        System.out.println("Can't load file!");
    }

    this.x = x;
    this.y = y;
}

/*
 * move the sprite based on key inputs
 */
public void move2() {
    this.x += this.speedKeyX;
    this.y += this.speedKeyY;
}

public void keyPressed(KeyEvent e) {
    if(e.getKeyCode() == KeyEvent.VK_LEFT) {
        speedKeyX = -1; //when move is, called change the speed
    }
    if(e.getKeyCode() == KeyEvent.VK_RIGHT) {
        speedKeyX = 1;
    }
}

public void keyReleased(KeyEvent e) {
    if(e.getKeyCode() == KeyEvent.VK_LEFT){
        speedKeyX = 0;
    }
    if(e.getKeyCode() == KeyEvent.VK_RIGHT){
        speedKeyX = 0;
    }
}

//GETTERS
public BufferedImage getImage(){ return this.img; }
public int getX(){ return this.x; }
public int getY(){ return this.y; }

//SETTERS
public void setX(int x){ this.x = x; }
public void setY(int y){ this.y = y; }

}

When I run the game and press left and right the sprite wont move! I don't know why...

Answer 1

I found the issue, I needed to set my JPanel to focusable() in order to handle input.

In my constructor I added:

this.setFocusable(true);

and everything works fine.