Adding a KeyListener to a JLabel?

[Josh Rodrigues]

Well, I'm making a game and I'm trying to add a KeyListener to a JLabel which contains an ImageIcon. Every time I press the up, down, right or left arrow key, they print out what I want it to print out, but do not do the action I wish for them to perform. Here's my code:

import javax.swing.JApplet;
import javax.swing.JPanel;
import javax.swing.JComponent;
import javax.swing.JProgressBar;
import javax.swing.JButton;
import javax.swing.JMenuBar;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JLabel;
import javax.swing.ImageIcon;
import java.awt.Graphics;
import java.awt.Dimension;
import java.awt.Color;
import java.awt.Container;
import java.awt.BorderLayout;
import java.awt.Toolkit;
import java.awt.Font;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.awt.event.KeyListener;
import java.awt.event.KeyEvent;
import java.io.IOException;
import java.net.URL;

public class GameApplet extends JApplet implements ActionListener, KeyListener {

	public JProgressBar load;
	public JPanel panel;
	public static JPanel main;
	public String title;
	public String imgPath = "./Sprites/";
	public JLabel imageLabel;
	public ImageIcon icon;
	public int xPos = 180;
	public int yPos = 180;

	public void init() {
		setProgress();
	}

	public void setProgress() {
		load = new JProgressBar();
		load.setPreferredSize(new Dimension(500, 85));
		load.setStringPainted(true);
		load.setFont(new Font("Dialog", 1, 10));
		drawLoadingText(100, "Loading Done!");
		panel = new JPanel();
		panel.setBackground(Color.black);
		panel.setPreferredSize(new Dimension(700, 600));
		JButton doneButton = new JButton("Done");
		doneButton.addActionListener(this);
		panel.add(load);
		panel.add(doneButton);
		add(panel);
	}

	public void drawLoadingText(int value, String text) {
		load.setValue(value);
		load.setString(text);
	}

	public void mainScreen() {
		main = new JPanel();
		main.setBackground(Color.black);
		main.setPreferredSize(new Dimension(700, 600));
		setImage();
		add(main);
	}

	public JMenuBar menuTask() {
		JMenuBar menuTaskBar = new JMenuBar();
		JMenu startMenu = new JMenu("Start");
		startMenu.setToolTipText("Click here to begin");
		menuTaskBar.add(startMenu);
		return menuTaskBar;
	}

	public void actionPerformed(ActionEvent e) {
		String cmd = e.getActionCommand();
		if (cmd.equals("Done")) {
			panel.setVisible(false);
			mainScreen();
		}
	}

	public void setImage() {
		icon = new ImageIcon(imgPath + "file.png");
		imageLabel = new JLabel(icon);
		imageLabel.setFocusable(true);
		imageLabel.requestFocus();
		imageLabel.addKeyListener(this);
		main.add(imageLabel);
	}

	public void keyPressed(KeyEvent ke) {
		int keyPad = ke.getKeyCode();
		if (keyPad == KeyEvent.VK_LEFT) {
			xPos -= 40;
			System.out.println("Left has been pressed!");
		} else if (keyPad == KeyEvent.VK_RIGHT) {
			xPos += 40;
			System.out.println("Right has been pressed!");
		} else if (keyPad == KeyEvent.VK_UP) {
			yPos += 40;
			System.out.println("Up has been pressed!");
		} else if (keyPad == KeyEvent.VK_DOWN) {
			yPos -= 40;
			System.out.println("Down has been pressed!");
		}
	}

	public void keyReleased(KeyEvent ke) {}
	public void keyTyped(KeyEvent ke) {}
}

I tried adding the requestFocus() method and a few different ways of creating the keyPressed(KeyEvent e) method. Help is appreciated. Thanks.

[Olivier Legat]

Hello Josh,

I don't see why anything should happen other than printing the text. In the keyPressed methods you are incrementing/decrementing the variables xPos and yPos, which are not ever used locally (other than in keyPressed). Unless these variables are used elsewhere, these variations are useless.