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Swing going from menu to actual gameplay

So I am making a space invaders clone. Originally I had no problem getting my game to work with a simple main class that created the frame, created the gameplay and started the thread.
But then I tried to implement a start menu and it all went to crap. The menu appears with success but the gameplay does not appear when I press start.
I am running out of ideas and I am completely stumped. I am somewhat new as well to SO, so if there is anything I left out, I appreciate any help.
Here is the original with no menu that worked fine:
public static void main(String[] args) {
JFrame frame = new JFrame("SpaceRaiders");
frame.setSize(600, 600);
frame.setLocationRelativeTo(null);
frame.setResizable(false);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Gameplay gameplay = new Gameplay();
frame.add(gameplay);
frame.setVisible(true);
Thread t1 = new Thread(gameplay);
t1.start();
}
However, the moment I tried to implement a menu to then play the game, I am running into all sorts of trouble. I created a UI class as well as an actual "game" class like so:
public class UI {
JFrame frame, f2;
JPanel titrePanel, startButtonPanel, loadButtonPanel, p2;
JLabel nomJeu;
JButton startButton, loadButton;
Font fontTitre, fontStart;
Gameplay gameplay;
public void createUI(ChoixJeu cj) {
frame = new JFrame("SpaceRaiders");
frame.setSize(600, 600);
frame.setLocationRelativeTo(null);
frame.setResizable(false);
frame.setLayout(null);
frame.getContentPane().setBackground(Color.black);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//------------------ECRAN MENU---------------------
//Titre
titrePanel = new JPanel();
titrePanel.setBounds(100, 100, 400, 100);
titrePanel.setBackground(Color.BLUE);
Font fontTitre = new Font("Times New Roman", Font.BOLD, 50);
Font fontStart = new Font("Times New Roman", Font.PLAIN, 20);
nomJeu = new JLabel("SpaceRaiders");
nomJeu.setForeground(Color.white);
nomJeu.setFont(fontTitre);
titrePanel.add(nomJeu);
//Start button
startButtonPanel = new JPanel();
startButtonPanel.setBounds(200, 400, 200, 40);
startButtonPanel.setBackground(Color.BLACK);
startButton = new JButton("START");
startButton.setBackground(Color.BLACK);
startButton.setForeground(Color.WHITE);
startButton.setFont(fontStart);
startButton.setFocusPainted(false);
startButton.addActionListener(cj);
startButton.setActionCommand("start");
startButtonPanel.add(startButton);
//Load Button
loadButtonPanel = new JPanel();
loadButtonPanel.setBounds(200, 440, 200, 100);
loadButtonPanel.setBackground(Color.BLACK);
loadButton = new JButton("LOAD");
loadButton.setBackground(Color.BLACK);
loadButton.setForeground(Color.WHITE);
loadButton.setFont(fontStart);
loadButton.setFocusPainted(false);
titrePanel.add(nomJeu);
loadButtonPanel.add(loadButton);
frame.add(startButtonPanel);
frame.add(titrePanel);
//------------------ECRAN MENU FIN---------------------
frame.setVisible(true);
}
And the game class...
public class Jeu {
ChoixJeu cj = new ChoixJeu();
UI ui = new UI();
Ecrans e = new Ecrans(ui);
Gameplay gp;
public static void main(String[] args) {
new Jeu();
}
public Jeu() {
ui.createUI(cj);
Gameplay gameplay = new Gameplay();
this.gp = gameplay;
}
public class ChoixJeu implements ActionListener {
#Override
public void actionPerformed(ActionEvent ae) {
String yourChoice = ae.getActionCommand();
switch (yourChoice) {
case "start":
e.montrerEcranJeu();
new Thread(gp).start();
ui.frame.add(gp);
break;
default:
break;
}
}
}
}
I also tried to make a class/method that hides the menu panels
public void montrerEcranJeu() {
//Cache Menu
ui.titrePanel.setVisible(false);
ui.startButtonPanel.setVisible(false);
//Montre Jeu
// ui.frame.add(gameplay);
}
And just in case the Gameplay class. The run() method is at the bottom
public class Gameplay extends JPanel implements KeyListener, ActionListener, Runnable {
private Ship player = new Ship(new Point(200, 555));
Timer t = new Timer(5, this);
private ArrayList<Laser> lasers = new ArrayList<Laser>();
private int laserNb;
private boolean readytofire;
private boolean shot = false;
private ArrayList<Invader> invaders = new ArrayList<Invader>();
private boolean pause;
public Gameplay() {
super();
t.start();
addKeyListener(this);
setFocusable(true);
setFocusTraversalKeysEnabled(false);
for (int j = 0; j < 80; j += 20) {
for (int i = 0; i < 20; i++) {
invaders.add(new Invader(5 + i * 30, j));
}
}
}
public boolean addLaser(Laser a) {
lasers.add(a);
return true;
}
public boolean addPlayer(Ship p) {
this.player = p;
return true;
}
#Override
public void keyTyped(KeyEvent ke) {
}
public void keyPressed(KeyEvent e) {
if (KeyEvent.VK_RIGHT == e.getKeyCode()) {
moveRight();
}
if (KeyEvent.VK_LEFT == e.getKeyCode()) {
moveLeft();
}
if (KeyEvent.VK_SPACE == e.getKeyCode()) {
shoot();
System.out.println("Space Action from Gameplay is working");
}
}
#Override
public void keyReleased(KeyEvent e) {
}
#Override
public void actionPerformed(ActionEvent ae) {
repaint();
}
public void moveRight() {
if (player.getCentre().getX() >= 580) {
player.setX(580);
} else {
double movement = player.getCentre().getX();
movement += 10;
player.setX(movement);
}
this.repaint();
}
public void moveLeft() {
if (player.getCentre().getX() <= 20) {
player.setX(20);
} else {
double movement = player.getCentre().getX();
movement -= 10;
player.setX(movement);
}
this.repaint();
}
public void shoot() {
shot = true;
if (readytofire) {
Point top = new Point(player.getTopX(), player.getTopY());
Laser laser = new Laser(top);
addLaser(laser);
}
}
public void moveShot() {
if (shot) {
for (Laser l : lasers) {
l.setY(l.getTopLeft().getY() - 1);
}
}
}
#Override
public void paint(Graphics g) {
setBackground(Color.black);
super.paint(g);
player.draw(g);
for (Laser l : lasers) {
l.draw(g);
}
for (Invader i : invaders) {
i.draw(g);
}
}
// public void paintComponent (Graphics g){
// Controle Thread
public void run() {
while (true) {
moveShot();
for (Invader i : invaders) {
i.moveAndUpdate();
}
// for (Invader i : invaders) {
// if (){
// System.out.println("YOU ARE DEAD!");
// }
// }
try {
Thread.sleep(10);
readytofire = true;
} catch (InterruptedException ex) {
Logger.getLogger(Gameplay.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
}

So, using null layouts is the beginning of your problems. I might recommend using CardLayout which is designed to help you dynamically switch between views. See How to Use CardLayout for more details. I'd also suggest taking the time to read through Laying Out Components Within a Container and finding one or more appropriate layouts to support your menu.
You're also making a lot of fundamental mistakes. Swing is not thread safe, so you should avoid updating the UI (or something the UI depends on) from outside the context of the EDT - see Concurrency in Swing for more information and How to Use Swing Timers for a possible solution.
As a general recommendation, you should avoid overriding paint and, in the case of classes which extend from JComponent, prefer paintComponent instead. You should also avoid call methods which might change the state of the component during a paint cycle, this can increase the number of repaint requests and degrade the performance of your program (ie, don't call setBackground inside paint).
Have a look at Performing Custom Painting and Painting in AWT and Swing for more details about how the paint system works and how best you can work with it.
You should also avoid KeyListener, this is likely to cause you issues when you introduce other, focusable, components into the picture. Instead, you should favour the Key bindings API instead
I've read through [insert link or tutorial], but it still doesn't help...
And forgive me if this doesn't happen all the time.
The point of providing you the tutorial links is to encourage you to learn something;
Learn where to find answers to your questions
Learn how the APIs work
Expand your knowledge and understanding of how the APIs work
Having said that, they're not always "obvious" as to the solution. What I do when I'm in this situation is start with one or more new projects, dedicated to just working on that aspect of the API I'm trying to understand. For here I can explore the concepts in isolation and when I "think" I understand them, try and implement them into the project I'm working on. This might take a number of iterations, but once it works, I have gained a much deeper understanding and appreciation of the API then I would have gained from a simple "copy-n-paste" solution

Implementing freehand draw in a MVC Java Swing project

I'm currently working on a project that involves using the Model-View-Controller architecture, in the project I have to implement freehand drawing inside of a JPanel, however the panel.paintComponent(g) method doesn't seem to work.
In my view package I create the GUI and give each object a getter, my controller class creates a GUI and uses these getters to instantiate the JPanels, JButtons etc. The Drawing model is passed the JPanel I want to draw on, as seen below.
public class Editor extends JPanel implements MouseListener, MouseMotionListener {
private int index = 0;
private Point[] arr = new Point[100000];
private JPanel xPanel = new JPanel();
Updater upDate = new Updater();
public void getPanel(JPanel dPanel)
{
xPanel = dPanel;
xPanel.addMouseListener(this);
xPanel.addMouseMotionListener(this);
xPanel.setBackground(Color.white);
}
public void paintComponent(Graphics g)
{
System.out.println("Got to this point");
xPanel.paintComponents(g);
for(int i = 0; i < index - 1; i++)
{
System.out.println("And here 2");
g.drawLine(arr[i].x, arr[i].y, arr[i+1].x, arr[i+1].y);
System.out.println("And here 3");
}
}
#Override
public void mousePressed(java.awt.event.MouseEvent e) {
arr[index] = new Point(e.getX(), e.getY());
index++;
System.out.println(index);
upDate.update(xPanel);
}
#Override
public void mouseDragged(java.awt.event.MouseEvent e) {
arr[index] = new Point(e.getX(), e.getY());
index++;
System.out.println(index);
upDate.update(xPanel);
}
My Controller class looks like this.
private GUI view;
private JButton buttonLoad;
private JButton buttonZoom;
private JButton buttonDrag;
private JButton buttonSave;
private JButton buttonRotate;
private JButton buttonDraw;
private JMenuBar menuB;
private JPanel dPanel;
private MouseListener e;
Graphics g;
public Controller(GUI gui){
this.view = gui;
menuB = view.getMenu();
buttonLoad = view.getLoad();
buttonZoom = view.getZoom();
buttonRotate = view.getRotate();
buttonSave = view.getSave();
buttonDrag = view.getDrag();
buttonDraw = view.getDraw();
dPanel = view.getModel();
g = dPanel.getGraphics();
FunctionListener x = new FunctionListener();
MenuBarListener y = new MenuBarListener();
buttonLoad.addActionListener(x);
buttonZoom.addActionListener(x);
buttonRotate.addActionListener(x);
buttonSave.addActionListener(x);
buttonDrag.addActionListener(x);
buttonDraw.addActionListener(x);
//menuB.addMenuListener(y);
}
class FunctionListener implements ActionListener{
#Override
public void actionPerformed(ActionEvent e)
{
if(e.getSource().equals(buttonZoom)){
Editor editor = new Editor();
editor.getPanel(dPanel);
editor.paintComponent(g);
}
It's worth noting that dPanel = view.getModel(); is a getter for a JPanel called Model in my GUI class. Everything seems to be working, the index of points is being returned properly yet there is no drawing, after running some simple System.out.println tests, I know that the code isn't entering the for loop in the Editor class.
Thanks for any help!

How can I add a JDesktopPane to an EditorTopComponent, from an ExplorerTopComponent?

I've been trying to call a method which displays frames in an EditorWindow, when pushing a button in the ExplorerWindow.
There are 3 modules:
AppEditorAPI which contains this interface
package org.app.AppEditorAPI;
public interface Displayer {
public void Display();
}
AppEditor which contains EditorTopComponent
#ServiceProvider(service=Displayer.class)
public final class EditorTopComponent extends TopComponent implements Displayer{
private JDesktopPane jdpDesktop=null;
private int openFrameCount = 0;
...
protected void createFrame() {
MyInternalFrame frame = new MyInternalFrame();
frame.setVisible(true);
jdpDesktop.add(frame);
try {
frame.setSelected(true);
} catch (java.beans.PropertyVetoException e) {
}
}
class MyInternalFrame extends JInternalFrame {
int xPosition = 30, yPosition = 30;
public MyInternalFrame() {
super("IFrame #" + (++openFrameCount), true, // resizable
true, // closable
true, // maximizable
true);// iconifiable
setSize(300, 300);
setLocation(xPosition / openFrameCount, yPosition / openFrameCount);
// Add some content:
add(new JLabel("hello IFrame #" + (openFrameCount)));
}
}
public void Display(){
jdpDesktop = new JDesktopPane();
createFrame(); // Create first window
createFrame(); // Create second window
createFrame(); // Create third window
//Add the JDesktop to the TopComponent
add(jdpDesktop);
}
}
And AppExplorer which contains ExplorerTopComponent
public final class ExplorerTopComponent extends TopComponent {
...
private void initComponents() {
B_Display = new javax.swing.JButton();
..
}
private void B_DisplayActionPerformed(java.awt.event.ActionEvent evt) {
Displayer D = Lookup.getDefault().lookup(Displayer.class);
D.Display();
}
...
}
Below, are links to the project zip file.
http://dl.free.fr/k2Z6DRLrW
http://www.fileswap.com/dl/lCeFPcUfbg/
After doing some tests. I found that I can't change (add, remove or edit) the variables or properties of the EditorTopComponent.
Like in this case, these two lines;
public void Display(){
jdpDesktop = new JDesktopPane();
...
add(jdpDesktop);
}
Are not executed as they should, that's why after the execution, the EditorTopComponent.jdpDesktop still was equal to null and wasn't added to the EditorTopComponent.
Knowing what I want to do, can someone please guide me on the right track ?

At last, 'made It work... see that's what happens when you avoid reading the books :P
I'm posting the solution if anyone's facing the same issue.
As I mentioned when editing my question, knowing that modifications are not allowed through the lookup, you can either use the InstanceContent variable which can be modified in the lookup, or, use the WindowManager to fitch the EditorTopComponent and call the Display() method.
Good luck

how to add an event to my slider code

How can I add an event to this code such that if i drag the slider, the number is displayed. Please, let me know as I am new to Java..
import javax.swing.*;
public class Slider extends JFrame {
JSlider pickNum = new JSlider(JSlider.HORIZONTAL, 0, 30, 5);
public Slider() {
super("Slider");
this.pack();
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
pickNum.setMajorTickSpacing(10);
pickNum.setMinorTickSpacing(1);
pickNum.setPaintTicks(true);
pickNum.setPaintLabels(true);
getPointedValue();
this.add(pickNum);
this.setVisible(true);
}
public final int getPointedValue() {
int value;
value = pickNum.getValue();
return value;
}
public static void main(String[] args) {
Slider frame = new Slider();
int i;
i = frame.getPointedValue();
System.out.println("current value is:" + i);
}
}

See addChangeListener(ChangeListener), as well as How to Use Sliders & How to Write a Change Listener.

As a concrete example using ChangeListener, SpinSlider shows how to connect a JSlider and a JSpinner.

Javax.swing timer repeats fine, but ActionListener doesn't do anything

I am trying to flash the background colour in a textfield. My timer setup is as follows:
Flash flash = new Flash(); //set up timer
tmr = new javax.swing.Timer(1000, new Flash());
tmr.addActionListener(flash);
tmr.setInitialDelay(0);
tmr.setRepeats(true);
tmr.start();
My actionListener is as follows:
static class Flash implements ActionListener
{
public void actionPerformed(ActionEvent evt)
{
if (flasher)
{
SpreademPanel.historyPnl.NameTxt.setBackground(Color.white);
}
else
{
SpreademPanel.historyPnl.NameTxt.setBackground(Color.pink);
}
flasher = !flasher;
} //actionPerformed
} //Flash
Now, when I put this in debug and follow the action, the program does repeatedly step through flash and toggle between the two alternatives. But onscreen, only the first toggle
occurs. After that, no action, although flash is still functioning.
What is wrong here?
Thanks in advance for any help.

This example continually varies the saturation of a panel's background color:
import java.awt.*;
import java.awt.event.*;
import java.awt.event.ActionListener;
import java.util.LinkedList;
import java.util.Queue;
import javax.swing.*;
public class FlashTest extends JPanel {
private static final Font font = new Font("Serif", Font.PLAIN, 32);
private static final String s = "Godzilla alert!";
FlashTest() {
this.setPreferredSize(new Dimension(256, 96));
this.setBackground(Color.red);
Timer t = new Timer(50, new Flash(this));
t.start();
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setFont(font);
int xx = this.getWidth();
int yy = this.getHeight();
int w2 = g.getFontMetrics().stringWidth(s) / 2;
int h2 = g.getFontMetrics().getDescent();
g.setColor(Color.black);
g.drawString(s, xx / 2 - w2, yy / 2 + h2);
}
private static class Flash implements ActionListener {
private final float N = 32;
private final JComponent component;
private final Queue<Color> clut = new LinkedList<Color>();
public Flash(JComponent component) {
this.component = component;
for (int i = 0; i < N; i++) {
clut.add(Color.getHSBColor(1, 1 - (i / N), 1));
}
for (int i = 0; i < N; i++) {
clut.add(Color.getHSBColor(1, i / N, 1));
}
}
#Override
public void actionPerformed(ActionEvent e) {
component.setBackground(clut.peek());
clut.add(clut.remove());
}
}
static public void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(new FlashTest());
f.pack();
f.setVisible(true);
}
});
}
}

There are a couple of problems here.
The first obvious thing is that you appear to be using mutable statics. This is a really bad idea and indicates (and causes!) confusion. In this particular case, one of the problems caused is that the flasher static is shared.
Flash flash = new Flash(); //set up timer
tmr = new javax.swing.Timer(1000, new Flash());
tmr.addActionListener(flash);
We are adding two Flash actions. Ordinarily this would be bad, but just produce an undetectable "bug". The colour would be set twice.
Bring these two things together, and we have two actions without a break that perform the same toggle. Two toggles. The state does not change (although there are repaint, property change events, etc.).
So, don't use mutable statics, and keep the code clean.

tmr = new javax.swing.Timer(1000, flash);

I tried your code and it works fine.
Why do you use a static context for SpreademPanel.historyPnl.NameTxt?
EDIT
You might want to redesign your class to pass the component in the constructor.
private class Flash implements ActionListener
{
private boolean flasher = false;
private JComponent component;
public Flash(JComponent component) {
this.component = component;
}
public void actionPerformed(ActionEvent evt)
{
if (flasher)
{
component.setBackground(Color.white);
}
else
{
component.setBackground(Color.pink);
}
flasher = !flasher;
} //actionPerformed
} //Flash
and then init it with
Flash flash = new Flash(SpreademPanel.historyPnl.NameTxt);
Timer tmr = new javax.swing.Timer(1000, flash);
tmr.start();