KeyListener deja de funcionar

[Neoff224]

Código:

import java.awt.BorderLayout;
import javax.swing.JPanel;
import java.awt.*;
import java.awt.event.*;
import java.awt.Toolkit;
import java.awt.Image;
import java.awt.event.MouseEvent;
import java.awt.event.ActionEvent;
import java.awt.event.MouseListener;
import javax.swing.*; 
import java.net.URL;

/**
 * Write a description of class MenuInicial here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */
public class MenuInicial extends JPanel
{
    private JLabel imgFacil = new JLabel();
    private JLabel imgNormal = new JLabel();
    private JLabel imgImposible = new JLabel();
    private JLabel imgComplicado = new JLabel();

    private static final int POSICION_X = 100;
    private static final int POSICION_FACIL = 100;
    private static final int POSICION_NORMAL = 200;
    private static final int POSICION_COMPLICADO = 300;
    private static final int POSICION_IMPOSIBLE = 400;
    
    /**
     * Constructor for objects of class MenuInicial
     */
    public MenuInicial()
    {
        Toolkit t = Toolkit.getDefaultToolkit();
        setSize(550, 550);
        setLayout(null);
        
        imgFacil.setIcon(new ImageIcon("Images/Facil.jpg"));
        imgFacil.addMouseListener(new MyMouseListener());
        imgFacil.setName("Facil");
        add(imgFacil);
        imgFacil.setBounds(POSICION_X, POSICION_FACIL, 261, 65);
        
        imgNormal.setIcon(new ImageIcon("Images/Normal.jpg"));
        imgNormal.addMouseListener(new MyMouseListener());
        add(imgNormal);
        imgNormal.setBounds(POSICION_X, POSICION_NORMAL, 261, 65);
        
        imgComplicado.setIcon(new ImageIcon("Images/Complicado.jpg"));
        imgComplicado.addMouseListener(new MyMouseListener());
        add(imgComplicado);
        imgComplicado.setBounds(POSICION_X, POSICION_COMPLICADO, 261, 65);
        
        imgImposible.setIcon(new ImageIcon("Images/Imposible.jpg"));
        imgImposible.addMouseListener(new MyMouseListener());
        add(imgImposible);
        imgImposible.setBounds(POSICION_X, POSICION_IMPOSIBLE, 261, 65);
    }

    public void iniciaJuego(int nivel)
    {
        JFrame frame = (JFrame)this.getTopLevelAncestor();
        frame.remove(this);
        frame.add(new Ventana(nivel), BorderLayout.CENTER);
        frame.pack();
        frame.setSize(1000, 550);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }
    
    public class MyMouseListener extends MouseAdapter
    {
        public void mouseClicked(MouseEvent e)
        {
            JLabel origen = (JLabel)e.getSource();
            if(origen.getName() == "Facil")
            {
                System.out.println("Hola");
                iniciaJuego(1); 
            }
            if(origen.getName() == "Normal")
            {
                //iniciaJuego(2); 
            }
            if(origen.getName() == "Complicado")
            {
                //iniciaJuego(3); 
            }
            if(origen.getName() == "Imposible")
            {
                //iniciaJuego(4); 
            }
        }
        
        public void mousePressed(MouseEvent e) {
        }

        public void mouseReleased(MouseEvent e) {
        }

        public void mouseEntered(MouseEvent e) {
        }

        public void mouseExited(MouseEvent e) {
        }
    }
}