Accessing method of parent from instanced class

Question

Heyo!
I don't know if this makes sense. But I can't figure out another way to do it. Hell, I can't even figure this out. :P
So. I've got this class:
        JPanel cp = new JPanel();
     JPanel menuScreen = new egMenuScreen();
     JPanel newGame = new egNewGameScreen();
     public EscapeGravityUI() {
          // Create toolkit and get screen size
          Toolkit toolkit = getToolkit();
          Dimension size = toolkit.getScreenSize();
          // Set size, title and close operation on main game window
          setSize(1024, 768);
          setTitle("Escape Gravity");
          setDefaultCloseOperation(EXIT_ON_CLOSE);
          // Remove border
          setUndecorated(true);
          // Instructions for centering game window
          setLocation(size.width/2 - getWidth()/2,
               size.height/2 - getHeight()/2);
          // Create JPanel and add to JFrame
          cp = menuScreen;
          getContentPane().add(cp);
          // Set KeyListener so we can close window in fullscreen
          this.addKeyListener(new KeyAdapter() {
               public void keyPressed(KeyEvent e) {
                    if(e.getKeyCode() == KeyEvent.VK_ESCAPE) {
                         System.exit(0);
                         //TODO add nice code for confirming exit
     public void changeScreen(String np) {
          getContentPane().remove(cp);
          if(np == "egngs") {
               JPanel p = new egNewGameScreen();
          getContentPane().add(p);
          repaint();
     }This class is supposed to be a "holder" for diffrent screens in my game. Every screen represented by a JPanel.
in egMenuScreen that looks like this:
public class egMenuScreen extends JPanel {
     public egMenuScreen() {
          // Setup the menu screen
          setBackground(Color.white);
          setSize(1024, 768);
          setLayout(null);
          setFocusable(false);
          // Create menu buttons
          JButton newGame = new JButton("New Game");
          newGame.setBounds(getWidth()/2-60, 60, 120, 30);
          newGame.addActionListener(new ActionListener() {
               public void actionPerformed(ActionEvent event) {
                    super.changeScreen("egngs");
          JButton loadSaved = new JButton("Load Saved");
          loadSaved.setBounds(getWidth()/2-60, 100, 120, 30);
          loadSaved.addActionListener(new ActionListener() {
               public void actionPerformed(ActionEvent event) {
                    System.out.println("Load Saved");
          JButton options = new JButton("Options");
          options.setBounds(getWidth()/2-60, 140, 120, 30);
          options.addActionListener(new ActionListener() {
               public void actionPerformed(ActionEvent event) {
                    System.out.println("Options");
          JButton quit = new JButton("Quit");
          quit.setBounds(getWidth()/2-60, 180, 120, 30);
          quit.addActionListener(new ActionListener() {
               public void actionPerformed(ActionEvent event) {
                    System.out.println("Quit");
                    System.exit(0);
          // Add buttons to JPanel
          this.add(newGame);
          this.add(loadSaved);
          this.add(options);
          this.add(quit);
}What I want to do is to change that egMenuScreen to another JPanel class that holds the other screen. I figured I needed to do that from the JFrame (EscapeGravityUI). So the method changeScreen() is supposed to handle that. However I don't know how to run that method from within that instanced JPanel class... does that even make sense?
I'd really appriciate any help!
Peace

Answer 1

Styrisen wrote:
I looked at CardLayout but that looks like it needs to always have the buttons visible. Huh??
I may be wrong, Very
but I want to change the entire screen and as I saw it that wasn't possible with card layout!You're not reading the same stuff that I'm reading.
Here's a simple seizure-inducing program program that uses CardLayout to change a JPanel that fills the entire JFrame. Each card is simply a JPanel of random color with a label at the top and a red circle of increasing size. The cards are swapped by way of a Swing Timer:
import java.awt.BasicStroke;
import java.awt.CardLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.Stroke;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.geom.Ellipse2D;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.Timer;
class CardLayoutFun4 extends JPanel
    private static final int DELAY = 100;
    private static final int CARD_COUNT = 180;
    private CardLayout cardlayout = new CardLayout();
    private Timer timer = new Timer(DELAY, new ActionListener()
        public void actionPerformed(ActionEvent e)
            cardlayout.next(CardLayoutFun4.this);
    public CardLayoutFun4()
        setLayout(cardlayout);
        setPreferredSize(new Dimension(1024, 768));
        addCards();
        timer.start();
    private void addCards()
        Random random = new Random();
        for (int i = 0; i < CARD_COUNT; i++)
            final int index = i;
            JPanel cardPanel = new JPanel()
                private final double diameter = 600 * (index + 1) / CARD_COUNT;
                protected void paintComponent(Graphics g)
                    super.paintComponent(g);
                    Graphics2D g2 = (Graphics2D) g;
                    g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                            RenderingHints.VALUE_ANTIALIAS_ON);
                    Stroke oldStroke = g2.getStroke();
                    g2.setStroke(new BasicStroke(5));
                    g2.setPaint(Color.red);
                    g2.draw(new Ellipse2D.Double(20, 80, diameter, diameter));
                    g2.setStroke(oldStroke);
            cardPanel.setBackground(new Color(
                    random.nextInt(128),
                    random.nextInt(128),
                    random.nextInt(128)));
            cardPanel.add(new JLabel(String.valueOf(i)));
            add(cardPanel, String.valueOf(i));
    private static void createAndShowUI()
        JFrame frame = new JFrame("CardLayoutFun4");
        frame.getContentPane().add(new CardLayoutFun4());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    public static void main(String[] args)
        java.awt.EventQueue.invokeLater(new Runnable()
            public void run()
                createAndShowUI();
}Edited by: Encephalopathic on Jan 19, 2008 8:06 PM