Why wont my Java program acknowledge any key strokes using KeyListener?

Question

I have literally no idea why my program isn't recognizing keyboard input. I have places print statements throughout the program to determine the issue, and I have determined that the keyPressed method never activates. This is for a game which I am making for a class project, and yes I am a relatively beginner programmer. Thanks in advance! (Code below)

import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

import javax.swing.ImageIcon;
import javax.swing.JApplet;


public class Dodger extends JApplet implements Runnable, KeyListener {

Thread myThread;

public Image bg;
public Image pic;
public boolean loaded;

public int cx, cy, speed, x, y;

public void init(){
    setSize(800,800);
    loaded = false;
    x = 2;
    y = 400;
    cx = 0;
    cy = 0;
    speed = 3;
    myThread = new Thread(this);
    myThread.start();
    addKeyListener(this);
}

public void run(){
    loadpic();
    repaint();
    while (myThread!=null)
    {

        try{
            myThread.sleep(18);
        }catch(InterruptedException e){
            e.printStackTrace();
        }
        repaint();
    }
}

public void upMotion(){
    cy = cy + speed;
}

public void downMotion(){
    cy = cy - speed;    
}

public void leftMotion(){
    cx = cx - speed;
}

public void rightMotion(){
    cx = cx + speed;
}

@Override
public void keyPressed(KeyEvent k) {

    if (k.getKeyCode() == KeyEvent.VK_LEFT) {
        System.out.println("work");
        leftMotion();
    }

    if (k.getKeyCode() == KeyEvent.VK_RIGHT) {
        rightMotion();
    }

    if (k.getKeyCode() == KeyEvent.VK_UP) {
        upMotion();
    }

    if (k.getKeyCode() == KeyEvent.VK_DOWN) {
        downMotion();
    }
}

@Override
public void keyReleased(KeyEvent e) {
}

@Override
public void keyTyped(KeyEvent e) {
}

public void loadpic(){
    bg = new ImageIcon(getClass().getResource("back.png")).getImage();
    pic = new ImageIcon(getClass().getResource("smile.png")).getImage();
    loaded = true;
    repaint();
}



public void paint(Graphics g){
    g.drawImage(bg, 0, 0, this);
    g.drawImage(pic, cx, cy, this);
}   
}

Answer 1

The key events are detected just fine when the applet is focusable & has focus. Managing focus has always been a problem with applets. The problem is mostly that Sun never bothered to specify the focus behavior that should ideally apply to a mixed page of focusable HTML elements and applet(s).

As per Tom's advice, add to the end of init()

setFocusable(true);

To be safe, also override:

public void start() {
    this.requestFocusInWindow();
}

As an aside, generally it is better to use key bindings in Swing. They also require the applet to have input focus.

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