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How do I add JLabels over the Graphics class

I created a test class for my pong game to be able to add JLabels on my JFrame. However when I used the graphics class, the JLabel does not show up and I can't fix the problem.
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Main extends JFrame {
JLabel label;
public Main() {
JPanel p = new JPanel();
p.setLayout(null);
label = new JLabel("Text inside");
label.setBounds(1100, 500, 200, 50);
p.add(label);
add(p);
setSize(1700, 712);
setTitle("Title");
setDefaultCloseOperation(EXIT_ON_CLOSE);
setLocationRelativeTo(null);
setVisible(true);
}
public void paint(Graphics g) {
g.setColor(Color.green);
g.fillRect(0, 0, 1700, 712);
g.setColor(Color.DARK_GRAY);
g.drawRect(1050, 450, 300, 200);
}
public static void main(String[] args) {
new Main();
}
}

The JavaDoc for Window.paint() clearly states:
If this method is reimplemented, super.paint(g) should be called so that lightweight components are properly rendered.
You don't do this, so your lightweight components (i.e. your JLabels) are no longer rendered.

Repaint() does not work after adding more components to JPanel in Swing, Java

I am starting with Java and want to make a simple pong game to get into the ways of displaying stuff in java. I have created 2 classes that both extend JPanel and call the repaint() function every 16.6 milliseconds. I added both to a JPanel which I added to the frame, but only the component I added first displays.
I've tried to revalidate() after repaint() in both classes and made sure that the Timer actually works and that it's actionPerformed() method is actually called.
This is the main method:
public class Main {
public static void main(String[] args){
JFrame frame = new JFrame("Pong");
//...
JPanel mainPanel = new JPanel();
mainPanel.add(new Player());
mainPanel.add(new Ball(frameWidth/2, frameHeight/2 -40));
frame.add(mainPanel);
}
}
This is the important code for the classes (It's basically the same for both of them):
public class Player extends JPanel {
public Player(){
setPreferredSize(new Dimension(Main.frameWidth, Main.frameHeight));
setBackground(Color.BLACK);
new Timer(1000/60, new ActionListener(){
public void actionPerformed(ActionEvent e){
update();
repaint();
}
}).start();
}
//...
public void paintComponent(Graphics g){
super.paintComponent(g);
g.setColor(Color.WHITE);
g.fillRect(x, y, width, height);
}
}
(Of coure I left things like #Override or unneseccary functions out to shorten the code)
This code only paints the Player, altough I want it to display all the components of mainPanel.
This is an example that you can (hopefully) run. I had to split it up into 3 files, since I suck at anonymus classes:
Main.java
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Main {
public static void main(String[] args){
JFrame frame = new JFrame("Pong");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(800, 800);
JPanel mainPanel = new JPanel();
mainPanel.add(new Player());
mainPanel.add(new Ball());
frame.add(mainPanel);
frame.setVisible(true);
}
}
///////
Player.java
//////
import javax.swing.JPanel;
import javax.swing.Timer;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Color;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class Player extends JPanel{
private int x = 20, y = 300, width = 20, height = 100;
public Player(){
setPreferredSize(new Dimension(800, 800));
setBackground(Color.BLACK);
new Timer(1000/60, new ActionListener(){
#Override
public void actionPerformed(ActionEvent e){
repaint();
}
}).start();
}
#Override
public void paintComponent(Graphics g){
super.paintComponent(g);
g.setColor(Color.WHITE);
g.fillRect(x, y, width, height);
}
}
//////
Ball.java
//////
import javax.swing.JPanel;
import javax.swing.Timer;
import java.awt.Graphics;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
public class Ball extends JPanel{
private int x = 20, y = 300, width = 20, height = 100;
public Ball(){
setPreferredSize(new Dimension(800, 800));
setBackground(Color.BLACK);
new Timer(1000/60, new ActionListener(){
#Override
public void actionPerformed(ActionEvent e){
repaint();
}
}).start();
}
#Override
public void paintComponent(Graphics g){
super.paintComponent(g);
g.setColor(Color.WHITE);
g.fillRect(x, y, width, height);
}
}

In method paintComponent() of class Player, you paint the exact same Rectangle each time. In order to achieve animation, each time you paint the rectangle you need to change either its size or location or both. What do you expect the Player to do? Should it move up and down along the left edge of the window? Have you seen the lesson entitled How to Use Swing Timers which is part of Oracle's Java Tutorial?
EDIT
I see now that Player hides Ball, because of the default layout manager of JPanel. The below code is essentially the code you posted but I set GridLayout as the layout manager for mainPanel. Also, a java source code file may contain more than one class but exactly one class must be public. Hence in the below code only class Main is public.
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
public class Main {
public static void main(String[] args) {
JFrame frame = new JFrame("Pong");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel mainPanel = new JPanel(new GridLayout(0, 2));
mainPanel.add(new Player());
mainPanel.add(new Ball());
frame.add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
}
class Player extends JPanel {
public Player() {
setBorder(BorderFactory.createLineBorder(Color.RED, 2, false));
setPreferredSize(new Dimension(800, 800));
setBackground(Color.BLACK);
new Timer(1000 / 60, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
repaint();
}
}).start();
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.WHITE);
g.fillRect(20, 100, 20, 100);
}
}
class Ball extends JPanel {
public Ball() {
setBorder(BorderFactory.createLineBorder(Color.CYAN, 2, false));
setPreferredSize(new Dimension(800, 800));
setBackground(Color.BLACK);
new Timer(1000 / 60, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
repaint();
}
}).start();
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.WHITE);
g.fillRect(300, 300, 10, 10);
}
}
And here is a screen capture of the GUI...

I just realized that if I extend my window manually, the second JPanel shows up under the one responsible for the Player! This means that I'll need to set the Panels position somehow, right?
#Abra

Why is graphics not showing on my JFrame / JPanel?

When I run this code. The result is a window with the name. Fully blank. I tried editing background color and adding graphics (rectangle) etc but the same result keeps occurring .
Question: This ends up as a white screen on a window. No graphics or background color. Even though I added it to panel and added panel. How do I fix this?
Main.java
package ball.tec.main;
import javax.swing.JFrame;
import ball.tec.frame.Frame;
public class Main {
public static void main(String[] args) {
String Version = "0.1.2";
Frame f = new Frame();
f.setVisible(true);
f.add();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setResizable(false);
f.setSize(1500, 1000);
f.setTitle("RedBall V: " + Version);
}
}
Frame.java
package ball.tec.frame;
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Frame extends JFrame{
private static final long serialVersionUID = 1L;
public boolean debug = false;
//Creating panel object
JPanel panel = new JPanel();
//Graphics displayed
public void paintComponent(Graphics g) {
//Firstly Nothing pops up
g.setColor(Color.RED);
g.drawRect(20, 40, 10, 10);
//And this doesn't work.
this.setBackground(Color.RED);
}
//Add everything to 'panel'
public void add() {
add(panel);
//Even if I put it here it doesn't work ;-;
this.setBackground(Color.RED);
this.pack();
}
}

You don't use paintComponent() in a JFrame. What you probably intended to do was create a third class, extending JPanel. Add your paintComponent() there.
public class MyPanel extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.RED);
g.drawRect(20, 40, 10, 10);
this.setBackground(Color.RED);
}
}
f.add(new MyPanel());

JPanel Possibly Overlapping?

So I have this problem with my code. Whenever I load up the game there is a red square in the center of the screen, and I have not programmed it to do so. I have tried to find the error for hours but I just can't see it. I think it has to do with the panels or something. The second thing is that when I press the button to draw the grid, only a small line appears. It is programmed to be much bigger than what it is, and it is not in the right location either. Below is all my code, and any help is greatly appreciated!!
package com.theDevCorner;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JMenuBar;
import javax.swing.JPanel;
public class Game extends JPanel implements ActionListener {
public static JButton grid = new JButton("Show Grid");
public static JPanel drawArea = new JPanel();
public static JMenuBar menu = new JMenuBar();
public static JPanel notDrawn = new JPanel();
public static boolean gridPressed = false;
public Game() {
grid.addActionListener(this);
}
public static void main(String args[]) {
Game game = new Game();
JFrame frame = new JFrame();
frame.setVisible(true);
frame.setSize(new Dimension(
Toolkit.getDefaultToolkit().getScreenSize().width, Toolkit
.getDefaultToolkit().getScreenSize().height));
frame.setTitle("Game");
frame.setAlwaysOnTop(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
menu.setSize(new Dimension(1600, 20));
menu.setLocation(0, 0);
notDrawn.setBackground(new Color(255, 0, 50));
notDrawn.setSize(100, 900);
notDrawn.add(grid);
notDrawn.setLayout(null);
grid.setSize(new Dimension(100, 25));
grid.setLocation(0, 25);
drawArea.setSize(new Dimension((Toolkit.getDefaultToolkit()
.getScreenSize().width), Toolkit.getDefaultToolkit()
.getScreenSize().height));
drawArea.setLocation(100, 0);
drawArea.setBackground(Color.black);
drawArea.add(menu);
drawArea.add(game);
frame.add(drawArea);
frame.add(notDrawn);
}
public void paint(Graphics g) {
Game game = new Game();
if (gridPressed) {
Game.drawGrid(0, 0, g);
}
g.dispose();
repaint();
}
public static void drawGrid(int x, int y, Graphics g) {
g.setColor(Color.white);
g.drawLine(x, y, 50, 300);
}
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == grid && gridPressed == true) {
gridPressed = false;
System.out.println("Unpressed");
}
if (e.getSource() == grid) {
gridPressed = true;
System.out.println("Pressed");
}
}
}

There are a number of problems...
The red "square" you are seeing is actually your grid button. The reason it's red is because of your paint method.
Graphics is a shared resource, that is, each component that is painted on the screen shares the same Graphics context. Because you chose to dispose of the context and because you've failed to honor the paint chain, you've basically screwed it up.
Don't EVER dispose of a Graphics context you didn't create. It will prevent anything from being painted to it again. Always call super.paintXxx. The paint chain is complex and does a lot of very important work. If you're going to ignore it, be ready to have to re-implement it.
null layouts are vary rarely the right choice, especially when you're laying out components. You need to separate your components from your custom painting, otherwise the components will appear above the custom painting.
This frame.setSize(new Dimension(Toolkit.getDefaultToolkit().getScreenSize().width, Toolkit.getDefaultToolkit().getScreenSize().height)) is not the way to maximize a window. This does not take into consideration the possibility of things like tasks bars. Instead use Frame#setExtendedState
As Andreas has already commented, you actionPerformed logic is wrong. You should be using an if-statement or simply flipping the boolean logic...
Updated with simple example
ps- static is not your friend here...
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Game extends JPanel implements ActionListener {
private GridPane gridPane;
public Game() {
setLayout(new BorderLayout());
SideBarPane sideBar = new SideBarPane();
sideBar.addActionListener(this);
add(sideBar, BorderLayout.WEST);
gridPane = new GridPane();
add(gridPane);
}
public static void main(String args[]) {
Game game = new Game();
JFrame frame = new JFrame();
frame.setVisible(true);
frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
frame.setTitle("Game");
frame.setAlwaysOnTop(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(game);
}
#Override
public void actionPerformed(ActionEvent e) {
if (e.getActionCommand().equalsIgnoreCase("grid")) {
gridPane.setGridOn(!gridPane.isGridOn());
}
}
public class GridPane extends JPanel {
private boolean gridOn = false;
public GridPane() {
setBackground(Color.BLACK);
}
public boolean isGridOn() {
return gridOn;
}
public void setGridOn(boolean value) {
if (value != gridOn) {
this.gridOn = value;
repaint();
}
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (gridOn) {
g.setColor(Color.white);
g.drawLine(0, 0, 50, 300);
}
}
}
public class SideBarPane extends JPanel {
public JButton grid;
public SideBarPane() {
setBackground(new Color(255, 0, 50));
setLayout(new GridBagLayout());
grid = new JButton("Show Grid");
grid.setActionCommand("grid");
GridBagConstraints gbc = new GridBagConstraints();
gbc.anchor = GridBagConstraints.NORTH;
gbc.weighty = 1;
add(grid, gbc);
}
public void addActionListener(ActionListener listener) {
grid.addActionListener(listener);
}
}
}

How to make a JPanel inside a JFrame fill the whole window?

In the below example, how can I get the JPanel to take up all of the JFrame? I set the preferred size to 800x420 but it only actually fills 792x391.
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics2D;
import java.awt.image.BufferStrategy;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class BSTest extends JFrame {
BufferStrategy bs;
DrawPanel panel = new DrawPanel();
public BSTest() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLayout(new BorderLayout()); // edited line
setVisible(true);
setSize(800,420);
setLocationRelativeTo(null);
setIgnoreRepaint(true);
createBufferStrategy(2);
bs = getBufferStrategy();
panel.setIgnoreRepaint(true);
panel.setPreferredSize(new Dimension(800,420));
add(panel, BorderLayout.CENTER); // edited line
panel.drawStuff();
}
public class DrawPanel extends JPanel {
public void drawStuff() {
while(true) {
try {
Graphics2D g = (Graphics2D)bs.getDrawGraphics();
g.setColor(Color.BLACK);
System.out.println("W:"+getSize().width+", H:"+getSize().height);
g.fillRect(0,0,getSize().width,getSize().height);
bs.show();
g.dispose();
Thread.sleep(20);
} catch (Exception e) { System.exit(0); }
}
}
}
public static void main(String[] args) {
BSTest bst = new BSTest();
}
}

If you are having only one panel in frame and nothing else then try this:
Set BorderLayout in frame.
Add panel in frame with BorderLayout.CENTER
May be this is happening because of while loop in JPanel.(Not sure why? finding actual reason. Will update when find it.) If you replace it with paintComponent(g) method all works fine:
public BSTest() {
//--- your code as it is
add(panel, BorderLayout.CENTER);
//-- removed panel.drawStuff();
}
public class DrawPanel extends JPanel {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
g2d.setColor(Color.BLACK);
System.out.println("W:" + getSize().width + ", H:" + getSize().height);
g2d.fillRect(0, 0, getSize().width, getSize().height);
}
}
//your code as it is.

Here's an alternative using pack instead.
import java.awt.Color;
import java.awt.Dimension;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class PackExample extends JFrame {
public PackExample(){
JPanel panel = new JPanel();
panel.setPreferredSize(new Dimension(800,600));
panel.setBackground(Color.green);
add(panel);
pack();
setVisible(true);
}
public static void main(String[] args){
new PackExample();
}
}

This took me forever to figure out but its actually the simplest code ever.
Just create a parent panel and pass GridLayout then add your child panel like this.
JPanel parentPanel= new JPanel(new GridLyout());
JPanel childPanel= new JPanel();
parentPanel.add(childPanel);

If you want to fill the JFrame with the whole of JPanel you need to setUndecorated to true i.e. frame.setUndecorated(true);. But now you have to worry about your MAXIMIZE< MINIMIZE, and CLOSE Buttons, towards the top right side(Windows Operating System)