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Snake game in Java but my restart button does not work

My restart button of the game does not work and it multiples when it is clicked. I do not understand Java perfectly I am considering myself good.
Main of the game
package snake_game;
public class snake {
public static void main(String arg[]) {
new GameFrame();
// is exacly the same as frame f = new frame();
// this is shorter and does the same job
}
}
GamePanel
package snake_game;
// import java.awt.event.ActionEvent;
// import java.awt.event.ActionListener;
// import java.awt.Graphics;
// import java.awt.event.KeyAdapter;
// import java.awt.event.KeyEvent;
// or I could write simply
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.Random;
import javax.swing.JPanel;
public class GamePanel extends JPanel implements ActionListener {
// panal dimentions
static final int SCREEN_WIDTH = 600;
static final int SCREEN_HEIGHT = 600;
// panal dimentions
// size
static final int UNIT_SIZE = 25;
// size to make 600 * 600 = 1200 px equel between 25 px
static final int GAME_UNITS = (SCREEN_WIDTH * SCREEN_HEIGHT) / UNIT_SIZE;
// size
// delay how fast the game will be
static final int DELAY = 75;
// delay
// dimentions
final int x[] = new int[GAME_UNITS];
final int y[] = new int[GAME_UNITS];
// dimentions
// snake
int bodyParts = 6;
// snake
// apple
int appleEaten;
int appleX;
int appleY;
// apple
char direction = 'R';
boolean running = false;
Timer timer;
Random random;
GamePanel game;
JButton resetButton;
GamePanel() {
random = new Random();
this.setPreferredSize(new Dimension(SCREEN_WIDTH, SCREEN_HEIGHT));
this.setBackground(Color.black);
this.setFocusable(true);
this.addKeyListener(new MyKeyAdapter());
startGame();
// when we want to make the program to continie we must say what the programm
// must execute next
}
public void startGame() {
newApple();
running = true;
timer = new Timer(DELAY, this);
timer.start();
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
draw(g);
}
public void draw(Graphics g) {
if (running) {
for (int i = 0; i < SCREEN_HEIGHT / UNIT_SIZE; i++) {
g.drawLine(i * UNIT_SIZE, 0, i * UNIT_SIZE, SCREEN_HEIGHT);
g.drawLine(0, i * UNIT_SIZE, i * SCREEN_WIDTH, i * UNIT_SIZE);
}
g.setColor(Color.red);
g.fillOval(appleX, appleY, UNIT_SIZE, UNIT_SIZE);
for (int i = 0; i < bodyParts; i++) {
if (i == 0) {
g.setColor(Color.green);
g.fillRect(x[i], y[i], UNIT_SIZE, UNIT_SIZE);
} else {
g.setColor(new Color(45, 180, 0));
// random color
g.setColor(new Color(random.nextInt(255), random.nextInt(255), random.nextInt(255)));
// random color
g.fillRect(x[i], y[i], UNIT_SIZE, UNIT_SIZE);
}
}
g.setColor(Color.red);
g.setFont(new Font("Ink Free", Font.BOLD, 30));
FontMetrics metrics = getFontMetrics(g.getFont());
g.drawString("SCORE:" + appleEaten, (SCREEN_WIDTH - metrics.stringWidth("SCORE:" + appleEaten)) / 2,
g.getFont().getSize());
} else {
gameOver(g);
}
}
public void newApple() {
appleX = random.nextInt((int) (SCREEN_WIDTH / UNIT_SIZE)) * UNIT_SIZE;
appleY = random.nextInt((int) (SCREEN_HEIGHT / UNIT_SIZE)) * UNIT_SIZE;
}
public void move() {
for (int i = bodyParts; i > 0; i--) {
x[i] = x[i - 1];
y[i] = y[i - 1];
}
switch (direction) {
case 'U':
y[0] = y[0] - UNIT_SIZE;
break;
case 'D':
y[0] = y[0] + UNIT_SIZE;
break;
case 'L':
x[0] = x[0] - UNIT_SIZE;
break;
case 'R':
x[0] = x[0] + UNIT_SIZE;
break;
}
}
public void checkApple() {
if ((x[0] == appleX) && (y[0] == appleY)) {
bodyParts++;
appleEaten++;
newApple();
}
}
public void checkCollisions() {
// check if head collides with body
for (int i = bodyParts; i > 0; i--) {
if ((x[0] == x[i]) && (y[0] == y[i])) {
running = false;
}
}
// check if head touches left border
if (x[0] < 0) {
running = false;
}
// check if head touches right border
if (x[0] > SCREEN_WIDTH) {
running = false;
}
// check if head touches top border
if (y[0] < 0) {
running = false;
}
// check if head touches bottom border
if (y[0] > SCREEN_HEIGHT) {
running = false;
}
if (!running) {
timer.stop();
}
}
public void gameOver(Graphics g) {
// score
g.setColor(Color.red);
g.setFont(new Font("Ink Free", Font.BOLD, 30));
FontMetrics metrics1 = getFontMetrics(g.getFont());
g.drawString("SCORE:" + appleEaten, (SCREEN_WIDTH - metrics1.stringWidth("SCORE:" + appleEaten)) / 2,
g.getFont().getSize());
// game over text
g.setColor(Color.red);
g.setFont(new Font("Ink Free", Font.BOLD, 75));
FontMetrics metrics2 = getFontMetrics(g.getFont());
g.drawString("Game Over", (SCREEN_WIDTH - metrics2.stringWidth("Game Over")) / 2, SCREEN_HEIGHT / 2);
// restart button
resetButton = new JButton();
resetButton.setText("Restart");
resetButton.setSize(100, 50);
resetButton.setLocation(150, 150);
resetButton.addActionListener(this);
game = new GamePanel();
this.add(resetButton);
this.add(game);
this.setVisible(true);
// restart button
}
#Override
public void actionPerformed(ActionEvent e) {
if (running) {
move();
checkApple();
checkCollisions();
}
repaint();
// restart button
if (e.getSource() == resetButton) {
this.remove(game);
game = new GamePanel();
this.add(game);
resetButton.setVisible(false);
SwingUtilities.updateComponentTreeUI(this);
// restart button
}
}
public class MyKeyAdapter extends KeyAdapter {
#Override
public void keyPressed(KeyEvent e) {
switch (e.getKeyCode()) {
case KeyEvent.VK_LEFT:
if (direction != 'R') {
direction = 'L';
}
break;
case KeyEvent.VK_RIGHT:
if (direction != 'L') {
direction = 'R';
}
break;
case KeyEvent.VK_UP:
if (direction != 'D') {
direction = 'U';
}
break;
case KeyEvent.VK_DOWN:
if (direction != 'U') {
direction = 'D';
}
break;
}
}
}
}
GameFrame
package snake_game;
import javax.swing.JFrame;
public class GameFrame extends JFrame {
GameFrame() {
GamePanel panel = new GamePanel();
this.add(panel);
this.setTitle("Snake");
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setResizable(false);
this.pack();
this.setVisible(true);
this.setLocationRelativeTo(null);
this.setUndecorated(false);
}
}

Introduction
I copied your code into my Eclipse IDE and ran it as is. I received the following runtime error.
Exception in thread "main" java.awt.IllegalComponentStateException: The frame is displayable.
at java.desktop/java.awt.Frame.setUndecorated(Frame.java:926)
at com.ggl.testing.SnakeGame$GameFrame.<init>(SnakeGame.java:41)
at com.ggl.testing.SnakeGame.main(SnakeGame.java:24)
Oracle has a helpful tutorial, Creating a GUI With Swing. Skip the Learning Swing with the NetBeans IDE section. Pay close attention to the Concurrency in Swing section.
I've been writing Swing code for over 10 years, and I have the Oracle website bookmarked in my browser. I still look up how to use certain components to make sure I'm using them correctly.
The first thing I did was to slow down your snake so I could test the game. I changed the delay of 75 to a delay of 750. Here's a screenshot of your current GUI.
Looking over your code, you extend a JFrame. You don't need to extend a JFrame. You're not changing any JFrame functionality. It's much simpler to use a JFrame. This leads to one of my Java rules.
Don't extend a Swing component, or any Java class, unless you intend
to override one or more of the class methods.
You do extend a JPanel. That's fine because you override the paintComponent method.
Finally, your JPanel class is doing too much work. You also make heavy use of static fields. Even though you'll only create one JPanel, it's a good habit to treat every class as if you will create multiple instances of the class. This creates fewer problems for yourself down the road.
You have the right idea, creating three classes.
So let's rework your code, using some basic patterns and Swing best practices. At this time, I don't know how many classes we'll wind up creating.
Explanation
When I write a Swing GUI, I use the model–view–controller (MVC) pattern. The name implies that you create a model first, then the view, then the controller(s).
An application model consists of one or more plain Java getter/setter classes.
A view consists of a JFrame, one or more JPanels, and any other necessary Swing components.
The controller consists of one or more Actions or ActionListeners. In Swing, there's usually not one controller to "rule them all".
To summarize:
The view reads information from the model
The view does not update the model
The controllers update the model and repaint/revalidate your view.
Model
I created two model classes, SnakeModel and Snake.
The SnakeModel class is a plain Java getter/setter class that holds one Snake instance, the apple eaten count, the apple location, the size of the game area, and a couple of booleans. One boolean indicates whether or not the game loop is running and the other boolean indicates whether or not the game is over.
The game area uses a java.awt.Dimension to hold the width and height of the game area. The width and the height do not have to have the same value. The game area can be rectangular.
The game area is measured in units. In the view, I convert the units into pixels. That's the opposite of what you did. If you want to change the game area, all you have to do is change the dimensions in the SnakeModel class. Everything in the view is based on the game area dimension.
The Snake class holds a java.util.List of java.awt.Point objects and a char direction. A java.awt.Point object holds an X and Y value. Since we're dealing with objects, rather than int values, we have to be careful to clone the object when we want a new Point.
View
All Swing applications must start with a call to the SwingUtilities invokeLater method. This method ensures that the Swing components are created and executed on the Event Dispatch Thread.
I created a JFrame, a drawing JPanel, and a separate button JPanel. Generally, it's not a good idea to add Swing components to a drawing JPanel. By creating a separate button JPanel, I get the added feature of a "Start Game" button at almost no extra cost. The button is disabled while the game is running.
The JFrame methods must be called in a specific order. The setVisible method must be called last.
I made the drawing JPanel more complicated by adding a separate area for the score.
I made the drawing JPanel less complicated by only drawing the state of the game, based on the application model. Period. Nothing else.
I limited the random colors to the white end of the color spectrum to maintain the contrast between the snake and the drawing JPanel background.
I used key bindings instead of a key listener. One advantage is that the drawing JPanel doesn't have to be in focus. Since I have a separate button JPanel, the drawing JPanel doesn't have focus.
Another advantage is that I can add the WASD keys with four lines of additional code.
One disadvantage is that the key bindings code looks more complicated than a key listener. Once you've coded a few key bindings, you'll appreciate the advantages.
Controller
I created three controller classes, ButtonListener, TimerListener, and MovementAction.
The ButtonListener class implements ActionListener. The ButtonListener class initializes the game model and restarts the timer.
The TimerListener class implements ActionListener. The TimerListener class is the game loop. This class moves the snake, checks to see if the apple is eaten, checks to see if the snake has moved outside the game area or touched itself, and repaints the drawing JPanel. I used your code as a model for the code in this class.
The MovementAction class extends AbstractAction. The AbstractAction class implements Action. This class changes the direction of the snake, based on the key presses.
I create four instances of the MovementAction class, one for each direction. This makes the actionPerformed method of the class much simpler.
Images
Here's what the revised GUI looks like when you start the game.
Here's the revised GUI during the game.
Here's the revised GUI when the game is over.
Code
Here's the complete runnable code. I made all the additional classes inner classes so I could post this code as one block.
You should put the separate classes in separate files.
When setting up a Swing GUI project, I create separate packages for the model, view, and controller. This helps me keep the code organized.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import javax.swing.AbstractAction;
import javax.swing.ActionMap;
import javax.swing.BorderFactory;
import javax.swing.InputMap;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.KeyStroke;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
public class SnakeGame implements Runnable {
public static void main(String arg[]) {
SwingUtilities.invokeLater(new SnakeGame());
}
private final GamePanel gamePanel;
private final JButton restartButton;
private final SnakeModel model;
public SnakeGame() {
this.model = new SnakeModel();
this.restartButton = new JButton("Start Game");
this.gamePanel = new GamePanel(model);
}
#Override
public void run() {
JFrame frame = new JFrame("Snake");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(gamePanel, BorderLayout.CENTER);
frame.add(createButtonPanel(), BorderLayout.SOUTH);
frame.pack();
frame.setResizable(false);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
private JPanel createButtonPanel() {
JPanel panel = new JPanel();
panel.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
panel.setBackground(Color.black);
restartButton.addActionListener(new ButtonListener(this, model));
panel.add(restartButton);
return panel;
}
public JButton getRestartButton() {
return restartButton;
}
public void repaint() {
gamePanel.repaint();
}
public class GamePanel extends JPanel {
private static final long serialVersionUID = 1L;
private final int margin, scoreAreaHeight, unitSize;
private final Random random;
private final SnakeModel model;
public GamePanel(SnakeModel model) {
this.model = model;
this.margin = 10;
this.unitSize = 25;
this.scoreAreaHeight = 36 + margin;
this.random = new Random();
this.setBackground(Color.black);
Dimension gameArea = model.getGameArea();
int width = gameArea.width * unitSize + 2 * margin;
int height = gameArea.height * unitSize + 2 * margin + scoreAreaHeight;
this.setPreferredSize(new Dimension(width, height));
setKeyBindings();
}
private void setKeyBindings() {
InputMap inputMap = this.getInputMap(JPanel.WHEN_IN_FOCUSED_WINDOW);
ActionMap actionMap = this.getActionMap();
inputMap.put(KeyStroke.getKeyStroke(KeyEvent.VK_UP, 0), "up");
inputMap.put(KeyStroke.getKeyStroke(KeyEvent.VK_DOWN, 0), "down");
inputMap.put(KeyStroke.getKeyStroke(KeyEvent.VK_LEFT, 0), "left");
inputMap.put(KeyStroke.getKeyStroke(KeyEvent.VK_RIGHT, 0), "right");
inputMap.put(KeyStroke.getKeyStroke(KeyEvent.VK_W, 0), "up");
inputMap.put(KeyStroke.getKeyStroke(KeyEvent.VK_S, 0), "down");
inputMap.put(KeyStroke.getKeyStroke(KeyEvent.VK_A, 0), "left");
inputMap.put(KeyStroke.getKeyStroke(KeyEvent.VK_D, 0), "right");
actionMap.put("up", new MovementAction(model, 'U', 'D'));
actionMap.put("down", new MovementAction(model, 'D', 'U'));
actionMap.put("left", new MovementAction(model, 'L', 'R'));
actionMap.put("right", new MovementAction(model, 'R', 'L'));
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Dimension gameArea = model.getGameArea();
drawHorizontalGridLines(g, gameArea);
drawVerticalGridLines(g, gameArea);
drawSnake(g);
drawScore(g, gameArea);
if (model.isGameOver) {
drawGameOver(g, gameArea);
} else {
drawApple(g);
}
}
private void drawHorizontalGridLines(Graphics g, Dimension gameArea) {
int y1 = scoreAreaHeight + margin;
int y2 = y1 + gameArea.height * unitSize;
int x = margin;
for (int index = 0; index <= gameArea.width; index++) {
g.drawLine(x, y1, x, y2);
x += unitSize;
}
}
private void drawVerticalGridLines(Graphics g, Dimension gameArea) {
int x1 = margin;
int x2 = x1 + gameArea.width * unitSize;
int y = margin + scoreAreaHeight;
for (int index = 0; index <= gameArea.height; index++) {
g.drawLine(x1, y, x2, y);
y += unitSize;
}
}
private void drawApple(Graphics g) {
// Draw apple
g.setColor(Color.red);
Point point = model.getAppleLocation();
if (point != null) {
int a = point.x * unitSize + margin + 1;
int b = point.y * unitSize + margin + scoreAreaHeight + 1;
g.fillOval(a, b, unitSize - 2, unitSize - 2);
}
}
private void drawScore(Graphics g, Dimension gameArea) {
g.setColor(Color.red);
g.setFont(new Font("Ink Free", Font.BOLD, 36));
FontMetrics metrics = getFontMetrics(g.getFont());
int width = 2 * margin + gameArea.width * unitSize;
String text = "SCORE: " + model.getApplesEaten();
int textWidth = metrics.stringWidth(text);
g.drawString(text, (width - textWidth) / 2, g.getFont().getSize());
}
private void drawSnake(Graphics g) {
// Draw snake
Snake snake = model.getSnake();
List<Point> cells = snake.getCells();
Point cell = cells.get(0);
drawSnakeCell(g, cell, Color.green);
for (int index = 1; index < cells.size(); index++) {
// Color color = new Color(45, 180, 0);
// random color
Color color = new Color(getColorValue(), getColorValue(),
getColorValue());
cell = cells.get(index);
drawSnakeCell(g, cell, color);
}
}
private void drawSnakeCell(Graphics g, Point point, Color color) {
int x = margin + point.x * unitSize;
int y = margin + scoreAreaHeight + point.y * unitSize;
if (point.y >= 0) {
g.setColor(color);
g.fillRect(x, y, unitSize, unitSize);
}
}
private int getColorValue() {
// White has color values of 255
return random.nextInt(64) + 191;
}
private void drawGameOver(Graphics g, Dimension gameArea) {
g.setColor(Color.red);
g.setFont(new Font("Ink Free", Font.BOLD, 72));
FontMetrics metrics = getFontMetrics(g.getFont());
String text = "Game Over";
int textWidth = metrics.stringWidth(text);
g.drawString(text, (getWidth() - textWidth) / 2, getHeight() / 2);
}
}
public class ButtonListener implements ActionListener {
private final int delay;
private final SnakeGame view;
private final SnakeModel model;
private final Timer timer;
public ButtonListener(SnakeGame view, SnakeModel model) {
this.view = view;
this.model = model;
this.delay = 750;
this.timer = new Timer(delay, new TimerListener(view, model));
}
#Override
public void actionPerformed(ActionEvent event) {
JButton button = (JButton) event.getSource();
String text = button.getText();
if (text.equals("Start Game")) {
button.setText("Restart Game");
}
button.setEnabled(false);
model.initialize();
timer.restart();
}
}
public class TimerListener implements ActionListener {
private final SnakeGame view;
private final SnakeModel model;
public TimerListener(SnakeGame view, SnakeModel model) {
this.view = view;
this.model = model;
}
#Override
public void actionPerformed(ActionEvent event) {
moveSnake();
checkApple();
model.checkCollisions();
if (model.isGameOver()) {
Timer timer = (Timer) event.getSource();
timer.stop();
model.setRunning(false);
view.getRestartButton().setEnabled(true);
}
view.repaint();
}
private void moveSnake() {
Snake snake = model.getSnake();
Point head = (Point) snake.getHead().clone();
switch (snake.getDirection()) {
case 'U':
head.y--;
break;
case 'D':
head.y++;
break;
case 'L':
head.x--;
break;
case 'R':
head.x++;
break;
}
snake.removeTail();
snake.addHead(head);
// System.out.println(Arrays.toString(cells.toArray()));
}
private void checkApple() {
Point appleLocation = model.getAppleLocation();
Snake snake = model.getSnake();
Point head = snake.getHead();
Point tail = (Point) snake.getTail().clone();
if (head.x == appleLocation.x && head.y == appleLocation.y) {
model.incrementApplesEaten();
snake.addTail(tail);
model.generateRandomAppleLocation();
}
}
}
public class MovementAction extends AbstractAction {
private static final long serialVersionUID = 1L;
private final char newDirection, oppositeDirection;
private final SnakeModel model;
public MovementAction(SnakeModel model, char newDirection,
char oppositeDirection) {
this.model = model;
this.newDirection = newDirection;
this.oppositeDirection = oppositeDirection;
}
#Override
public void actionPerformed(ActionEvent event) {
if (model.isRunning()) {
Snake snake = model.getSnake();
char direction = snake.getDirection();
if (direction != oppositeDirection && direction != newDirection) {
snake.setDirection(newDirection);
// System.out.println("New direction: " + newDirection);
}
}
}
}
public class SnakeModel {
private boolean isGameOver, isRunning;
private int applesEaten;
private Dimension gameArea;
private Point appleLocation;
private Random random;
private Snake snake;
public SnakeModel() {
this.random = new Random();
this.snake = new Snake();
this.gameArea = new Dimension(24, 24);
}
public void initialize() {
this.isRunning = true;
this.isGameOver = false;
this.snake.initialize();
this.applesEaten = 0;
Point point = generateRandomAppleLocation();
// Make sure first apple isn't under snake
int y = (point.y == 0) ? 1 : point.y;
this.appleLocation = new Point(point.x, y);
}
public void checkCollisions() {
Point head = snake.getHead();
// Check for snake going out of the game area
if (head.x < 0 || head.x > gameArea.width) {
isGameOver = true;
return;
}
if (head.y < 0 || head.y > gameArea.height) {
isGameOver = true;
return;
}
// Check for snake touching itself
List<Point> cells = snake.getCells();
for (int index = 1; index < cells.size(); index++) {
Point cell = cells.get(index);
if (head.x == cell.x && head.y == cell.y) {
isGameOver = true;
return;
}
}
}
public Point generateRandomAppleLocation() {
int x = random.nextInt(gameArea.width);
int y = random.nextInt(gameArea.height);
this.appleLocation = new Point(x, y);
return getAppleLocation();
}
public void incrementApplesEaten() {
this.applesEaten++;
}
public boolean isRunning() {
return isRunning;
}
public void setRunning(boolean isRunning) {
this.isRunning = isRunning;
}
public boolean isGameOver() {
return isGameOver;
}
public void setGameOver(boolean isGameOver) {
this.isGameOver = isGameOver;
}
public Dimension getGameArea() {
return gameArea;
}
public int getApplesEaten() {
return applesEaten;
}
public Point getAppleLocation() {
return appleLocation;
}
public Snake getSnake() {
return snake;
}
}
public class Snake {
private char direction;
private List<Point> cells;
public Snake() {
this.cells = new ArrayList<>();
initialize();
}
public void initialize() {
this.direction = 'R';
cells.clear();
for (int x = 5; x >= 0; x--) {
cells.add(new Point(x, 0));
}
}
public void addHead(Point head) {
cells.add(0, head);
}
public void addTail(Point tail) {
cells.add(tail);
}
public void removeTail() {
cells.remove(cells.size() - 1);
}
public Point getHead() {
return cells.get(0);
}
public Point getTail() {
return cells.get(cells.size() - 1);
}
public char getDirection() {
return direction;
}
public void setDirection(char direction) {
this.direction = direction;
}
public List<Point> getCells() {
return cells;
}
}
}

Java - Pac-Man - GUI - Drawing Graphics issue, and general tips for an aspiring programmer

I am making Pac-Man and I'm having trouble with drawing graphics on a frame, when i draw my point image it looks like a game of snake, i tried putting my drawing methods for background and char both in the render method, but than my point image flickers
What it currently looks like, feel free to ignore the random face it was an inside joke.
Also this is my very first game so any tips on structure, pointers on what I am doing right (if anything) and what I'm doing wrong, and general tips would be extremely helpful!
Also I am aware that i have a couple unused methods
Code:
package game;
import graphics.map;
import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JButton;
import javax.swing.JFrame;
public class main extends Canvas implements Runnable{
private static final long serialVersionUID = 1L; //not sure why it wanted me to do this, maybe ask bender, or just google it later
public static boolean running = false;
public static int HEIGHT = 800;
public static int WIDTH = 600;
public static int posX = 50;
public static int posY = 50;
public static final String name = "Pac Man Alpha 1.4";
private static final double speed = 1.2;
public input input;
static BufferedImage background = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);;
static BufferedImage pacman = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);;
static BufferedImage settingsBackground = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);;
static BufferedImage level1 = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);;
static BufferedImage level2 = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);;
static BufferedImage points = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);;
static BufferedImage point = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);;
static JFrame frame;
private input keypress = new input();
private map map;
private static boolean charLoaded = false;
public static boolean MAIN_MENU = true;
public static boolean GAME = false;
public static boolean level1test = true;
public static boolean level2test = false;
public static boolean level3test = false;
public static boolean level4test = false;
static boolean drawn = false;
public static boolean key_down;
public static boolean key_up;
public static boolean key_right;
public static boolean key_left;
//private Screen screen;
JButton startButton = new JButton("Start"); //Start
JButton settingsButton = new JButton("Settings"); //Settings
JButton exitButton = new JButton("Exit"); //Exit
public main()
{
setMinimumSize(new Dimension(WIDTH , HEIGHT ));
setMaximumSize(new Dimension(WIDTH , HEIGHT )); // keeps the canvas same size
setPreferredSize(new Dimension(WIDTH, HEIGHT));
frame = new JFrame(name);
if(MAIN_MENU == true && GAME == false){
buttons(frame.getContentPane());
}
frame.setLayout(new BorderLayout());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // ends program on
// close
frame.addKeyListener(new input() );
frame.add(this, BorderLayout.CENTER);
frame.pack(); // keeps size correct
frame.setResizable(false);
frame.setVisible(true);
this.addKeyListener(keypress);
}
public static void main(String[] args)
{
try {
background = ImageIO.read(new File("res\\Background.png"));
pacman = ImageIO.read(new File("res\\pacmansprites.png"));
settingsBackground = ImageIO.read(new File("res\\Background.png"));
level1 = ImageIO.read(new File("res\\level1.png"));
//level2 = ImageIO.read(new File("res\\level2.png"));
point = ImageIO.read(new File("res\\Points for pacman.png"));
} catch (IOException e) {
}
running = true;
new main().start();
}
public void run()
{
long lastTime = System.nanoTime();
double nsPerTick = 1000000000 / 60D;
long lastTimer = System.currentTimeMillis();
double delta = 0;
int frames = 0;
int ticks = 0;
while (running == true) {
long now = System.nanoTime();
delta += (now - lastTime) / nsPerTick;
lastTime = now;
boolean render = false;
while (delta >= 1) {
ticks++;
tick();
delta -= 1;
render = true;
}
try {
Thread.sleep(3); //keep the Frames from going to high
} catch (InterruptedException e) {
e.printStackTrace();
}
if(render == true){
frames++;
render();
}
if (System.currentTimeMillis() - lastTimer >= 1000) {
lastTimer +=1000;
//System.out.println("Frames: " + frames + " Ticks: " + ticks);
frames = 0;
ticks = 0;
}
}
}
public synchronized void start()
{
new Thread(this).start();
run();
}
public synchronized void stop()
{
running = false;
}
public void tick()
{
if (key_up) posY -= speed / 2;
if (key_down) posY += speed;
if (key_left) posX -= speed / 2;
if (key_right) posX += speed;
}
public void render()
{
drawn = false;
if(MAIN_MENU == false && GAME == true)
{
drawMap();
drawChar();
}
else if(MAIN_MENU == false && GAME == false) {
Graphics g = getGraphics();
{
g.drawImage(settingsBackground,0,0,getWidth(),getHeight(),null);
g.dispose();
}
} else {
Graphics g = getGraphics();{
g.drawImage(background,0,0,getWidth(), getHeight(),null);
g.dispose(); //kill it
}
}
}
public void drawMap(){
if(level1test == true){
Graphics g = getGraphics();
{
g.drawImage(level1,0,0,getWidth(),getHeight(),null);
g.dispose();
}
}
if(level2test == true && drawn == false){
Graphics g = getGraphics();
{
g.drawImage(level2,0,0,getWidth(),getHeight(),null);
}
g.dispose();
}
drawn = true;
}
public void drawChar(){
//drawMap();
Graphics g = getGraphics();{
g.drawImage(point,posX,posY,20, 20,null);
g.dispose();
revalidate();
}
}
public void begin() {
if (key_up) System.out.println("up");
if (key_down) System.out.println("down");
if (key_left) System.out.println("left");
if (key_right) System.out.println("right");
}
public void loadMap(){
if(!drawn && level1test){
}else if(!drawn && level2test){
//draw 2nd map here
}else if(!drawn && level3test){
//draw 3rd map here
}
}
public void buttons(Container pane)
{
pane.setLayout(null);
startButton.addActionListener( new ActionListener() {
public void actionPerformed(ActionEvent ae) {
MAIN_MENU = false;
GAME = true;
frame.remove(startButton);
frame.remove(settingsButton);
frame.remove(exitButton);
frame.revalidate();
drawMap();
System.out.println("Start Button Clicked");
}
} );
settingsButton.addActionListener( new ActionListener() {
public void actionPerformed(ActionEvent ae) {
MAIN_MENU = false;
GAME = false;
frame.remove(startButton);
frame.remove(settingsButton);
frame.remove(exitButton);
frame.revalidate();
frame.repaint();
System.out.println("Settings Button Clicked");
}
} );
exitButton.addActionListener( new ActionListener() {
public void actionPerformed(ActionEvent ae) {
System.out.println("Exit Button Clicked");
System.exit(0);
}
} );
pane.add(startButton);
pane.add(settingsButton);
pane.add(exitButton);
Insets insets = pane.getInsets();
Dimension size = startButton.getPreferredSize();
startButton.setBackground(new Color(0, 0, 0));
startButton.setForeground(Color.CYAN);
startButton.setFocusPainted(false);
startButton.setFont(new Font("Calabri", Font.BOLD, 16));
settingsButton.setBackground(new Color(0, 0, 0));
settingsButton.setForeground(Color.RED);
settingsButton.setFocusPainted(false);
settingsButton.setFont(new Font("Calabri", Font.BOLD, 16));
exitButton.setBackground(new Color(0, 0, 0));
exitButton.setForeground(Color.YELLOW);
exitButton.setFocusPainted(false);
exitButton.setFont(new Font("Calabri", Font.BOLD, 16));
startButton.setBounds((WIDTH - 125) + insets.left, 10 + insets.top,
size.width + 50, size.height + 10);
settingsButton.setBounds((WIDTH - 125) + insets.left, 55 + insets.top,
size.width + 50, size.height + 10);
exitButton.setBounds((WIDTH - 125) + insets.left, 100 + insets.top,
size.width + 50, size.height + 10);
}
}

getGraphics is not how custom painting is done. You should, in your case, override the paint method, and make sure you call super.paint before doing any custom painting.
getGraphics returns the Graphics context last used to paint the component, which could be discarded on the next paint cycle, be null or no longer used by the component
Remember, painting uses the "painters canvas" approach, that is, just like painting in a physical canvas, when you paint into it, you paint over what was previously there, but not erasing it.
Now, if you override paint, you will find that you will have a flickering problem. This is because Canvas
is not double buffered
To solve this, you should consider user a BufferStrategy, which allows you to not only generate multiple buffers to paint to, but also to take control of the paint process itself
Just don't forget to clear each buffer before you paint to it...

Double buffering is the trick that allows you to have flicker-free animation. Basically you have two representations of your canvas, one that's currently being displayed and one that you can draw on. If you're finished with drawing, you copy the draw-canvas over the display-canvas. Depending on system and hardware there are more elegant ways where you can just tell the hardware to switch canvases (page flipping).
Without double buffering or a similar techniques, it is almost impossible to have flicker-free animation.
With double buffering you can afford to draw the background and then the foreground sprites. It is possibly more efficient to draw only those parts of the background that have been destroyed by the foreground sprites (there are various techniques for that as well, including of taking a snapshot image of the affected areas before you paint the sprites).
You can find a simple example for Java double buffering here. Java's BufferStrategy is a more complex solution that can use hardware features for page flipping.

I think the problem is that you only draw onto the image background, never erasing the old drawing from your image. You will need to clear the area and then start drawing in order to get your desired results.
I have never attempted to make a game but when I do simple animations I usually will do them on a JFrame or JPanel. With a JFrame you can Override the paint() method and with a JPanel, the paintComponent() method. It helps to keep everything that I'm drawing centralized, which makes it much easier for me to modify my code. When you call the respective super method in your overridden method, it will start you off with a clean slate, meaning you will have to paint the (image) background and your characters all over again. Calling the super method is also necessary to paint that component's children if you decide to add anything onto the JFrame/JPanel.
If you chose to use one of the above then I would recommend a JPanel due to it offering double buffering, which will help make your animations look smooth/fluid. Also, do not forget to call repaint();.
Here is a quick example, which can be used to duplicate your issue if you comment out super.paintComponent(g);.
*Note that I am extending and using a JPanel for this example.
Code:
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Trial extends JPanel{
public static void main(String[] args)
{
new Trial();
}
int x = 5; // will represent the x axis position for our crude animation.
javax.swing.Timer timer = new javax.swing.Timer( 500, new ActionListener(){
// Timer used to control the animation and
// the listener is used to update x position and tell it to paint every .5 seconds.
#Override
public void actionPerformed(ActionEvent e) {
x += 5;
if ( x > 250)
timer.stop();
repaint(); // will call the paintComponent method.
}
});
Trial()
{
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationRelativeTo(null);
frame.add(this);
frame.setSize(300, 200);
frame.setVisible(true);
timer.start();
}
#Override
public void paintComponent(Graphics g)
{
super.paintComponent(g); // calling the super paintComponent method to paint children. can comment it
// out to duplicate your error, which happens when the frame isn't "refreshed".
Graphics2D g2d = (Graphics2D) g.create(); // creating a copy of the graphics object. // I do this to not alter the original
// Good practice and also Graphics2D
// offers a bit more to work with.
g2d.drawString("Graphics", x, 60); // painting a string.
g2d.drawRect(x, 80, 10, 10); // painting a rectangle.
}
}
Edit:
If you have a bunch of stuff to do and don't want to add it all into your paintComponent(); method you could create a method for various things and call them from inside your Overriden paint method, you could also pass them your graphics object. It will help you keep things relatively simple.

Text Banner applet reverses that displayes text

i'm working on applet that displays a moving banner horizontally and when this text banner
reaches the right boundary of the applet window it should be appear reversed from the start of the left boundary, i write the following class to do the work, the problem is that when the text banner reaches the right banner it crashes, the applet goes to infinite loop:
import java.applet.*;
import java.awt.*;
import java.net.*;
import java.io.*;
import javax.swing.*;
/*
<applet code="banner" width=300 height=50>
</applet>
*/
public class TextBanner extends Applet implements Runnable
{
String msg = "Islam Hamdy", temp="";
Thread t = null;
int state;
boolean stopFlag;
int x;
String[] revMsg;
int msgWidth;
boolean isReached;
public void init()
{
setBackground(Color.BLACK);
setForeground(Color.YELLOW);
}
// Start thread
public void start()
{
t = new Thread(this);
stopFlag = false;
t.start();
}
// Entry point for the thread that runs the banner.
public void run()
{
// Display banner
while(true)
{
try
{
repaint();
Thread.sleep(550);
if(stopFlag)
break;
} catch(InterruptedException e) {}
}
}
// Pause the banner.
public void stop()
{
stopFlag = true;
t = null;
}
// Display the banner.
public void paint(Graphics g)
{
String temp2="";
System.out.println("Temp-->"+temp);
int result=x+msgWidth;
FontMetrics fm = g.getFontMetrics();
msgWidth=fm.stringWidth(msg);
g.setFont(new Font("ALGERIAN", Font.PLAIN, 30));
g.drawString(msg, x, 40);
x+=10;
if(x>bounds().width){
x=0;
}
if(result+130>bounds().width){
x=0;
while((x<=bounds().width)){
for(int i=msg.length()-1;i>0;i--){
temp2=Character.toString(msg.charAt(i));
temp=temp2+temp;
// it crashes here
System.out.println("Before draw");
g.drawString(temp, x, 40);
System.out.println("After draw");
repaint();
}
x++;
} // end while
} //end if
}
}

Let's start with...
Use Swing over AWT components (JApplet instead of Applet)
Don't override the paint methods of top level containers. There are lots of reasons, the major one that is going to effect you is top level containers are not double buffered.
DO NOT, EVER, update the UI from any thread other the Event Dispatching Thread, in fact, for what you are trying to do, a Thread is simply over kill.
DO NOT update animation states with the paint method. You've tried to perform ALL you animation within the paint method, this is not how paint works. Think of paint as a frame in film, it is up to (in your case) the thread to determine what frame where up to, and in fact, it should be preparing what should painted.
You do not control the paint system. repaint is a "request" to the paint sub system to perform an update. The repaint manager will decide when the actual repaint will occur. This makes performing updates a little tricky...
Updated with Example
public class Reverse extends JApplet {
// Set colors and initialize thread.
public void init() {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
setBackground(Color.BLACK);
setForeground(Color.YELLOW);
setLayout(new BorderLayout());
add(new TextPane());
}
});
}
// Start thread
public void start() {
}
// Pause the banner.
public void stop() {
}
public class TextPane extends JPanel {
int state;
boolean stopFlag;
char ch;
int xPos;
String masterMsg = "Islam Hamdy", temp = "";
String msg = masterMsg;
String revMsg;
int msgWidth;
private int direction = 10;
public TextPane() {
setOpaque(false);
setBackground(Color.BLACK);
setForeground(Color.YELLOW);
setFont(new Font("ALGERIAN", Font.PLAIN, 30));
// This only needs to be done one...
StringBuilder sb = new StringBuilder(masterMsg.length());
for (int index = 0; index < masterMsg.length(); index++) {
sb.append(masterMsg.charAt((masterMsg.length() - index) - 1));
}
revMsg = sb.toString();
// Main animation engine. This is responsible for making
// the decisions on where the animation is up to and how
// to react to the edge cases...
Timer timer = new Timer(100, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
xPos += direction;
FontMetrics fm = getFontMetrics(getFont());
if (xPos > getWidth()) { // this condition fires when the text banner reaches the right banner
direction *= -1;
msg = revMsg;
} else if (xPos < -fm.stringWidth(masterMsg)) {
direction *= -1;
msg = masterMsg;
}
repaint();
}
});
timer.setRepeats(true);
timer.setCoalesce(true);
timer.start();
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
System.out.println(xPos);
FontMetrics fm = g.getFontMetrics();
msgWidth = fm.stringWidth(msg);
g.drawString(msg, xPos, 40);
}
}
}
Updated with additional example
Now, if you want to be a little extra clever...you could take advantage of a negative scaling process, which will reverse the graphics for you...
Updated timer...
Timer timer = new Timer(100, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
xPos += direction;
FontMetrics fm = getFontMetrics(getFont());
System.out.println(xPos + "; " + scale);
if (scale > 0 && xPos > getWidth()) { // this condition fires when the text banner reaches the right banner
xPos = -(getWidth() + fm.stringWidth(msg));
scale = -1;
} else if (scale < 0 && xPos >= 0) {
xPos = -fm.stringWidth(msg);
scale = 1;
}
repaint();
}
});
And the updated paint method...
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
g2d.scale(scale, 1);
FontMetrics fm = g2d.getFontMetrics();
msgWidth = fm.stringWidth(msg);
g2d.drawString(msg, xPos, 40);
g2d.dispose();
}
Updated with "bouncing"...
This replaces the TextPane from the previous example
As the text moves beyond the right boundary, it will "reverse" direction and move back to the left, until it passes beyond that boundary, where it will "reverse" again...
public class TextPane public class TextPane extends JPanel {
int state;
boolean stopFlag;
char ch;
int xPos;
String msg = "Islam Hamdy";
int msgWidth;
private int direction = 10;
public TextPane() {
setBackground(Color.BLACK);
setForeground(Color.YELLOW);
setFont(new Font("ALGERIAN", Font.PLAIN, 30));
Timer timer = new Timer(100, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
xPos += direction;
FontMetrics fm = getFontMetrics(getFont());
if (xPos > getWidth()) {
direction *= -1;
} else if (xPos < -fm.stringWidth(msg)) {
direction *= -1;
}
repaint();
}
});
timer.setRepeats(true);
timer.setCoalesce(true);
timer.start();
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
FontMetrics fm = g2d.getFontMetrics();
msgWidth = fm.stringWidth(msg);
g2d.drawString(msg, xPos, 40);
g2d.dispose();
}
}

I now think you mean 'should jump back to the start', but this slides back. But as an aside, I would not consider an applet for this sort of thing, for two reasons.
Scrolling text sucks.
If the page 'must have' scrolling text, better to do it using HTML and JS (and CSS).
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
/*
* <applet code="TextBanner" width=600 height=50> </applet>
*/
public class TextBanner extends JApplet {
private TextBannerPanel banner;
// Set colors and initialize thread.
#Override
public void init() {
banner = new TextBannerPanel("Islam Hamdy");
add(banner);
}
// Start animation
#Override
public void start() {
banner.start();
}
// Stop animation
#Override
public void stop() {
banner.stop();
}
}
class TextBannerPanel extends JPanel {
String msg;
int x;
int diff = 5;
Timer timer;
Font font = new Font("ALGERIAN", Font.PLAIN, 30);
public TextBannerPanel() {
new TextBannerPanel("Scrolling Text Banner");
}
public TextBannerPanel(String msg) {
this.msg = msg;
setBackground(Color.BLACK);
setForeground(Color.YELLOW);
ActionListener animate = new ActionListener() {
#Override
public void actionPerformed(ActionEvent ae) {
repaint();
}
};
timer = new Timer(100, animate);
}
// Display the banner.
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setFont(font);
FontMetrics fm = g.getFontMetrics();
int w = (int) fm.getStringBounds(msg, g).getWidth();
g.drawString(msg, x, 40);
x += diff;
diff = x+w > getWidth() ? -5 : diff;
diff = x < 0 ? 5 : diff;
}
public void start() {
timer.start();
}
public void stop() {
timer.stop();
}
}
Old answer
..should .. appear reversed .. "Islam Hamdy"
See also JArabicInUnicode:
import javax.swing.*;
import java.awt.*;
/**
* "Peace Be Upon You", "Aslam Alykm' to which the common reply is "Wa alaykum
* as salaam", "And upon you, peace". Information obtained from the document
* http://www.unicode.org/charts/PDF/U0600.pdf Copyright © 1991-2003
* Unicode, Inc. All rights reserved. Arabic is written and read from right to
* left. This source is adapted from the original 'Peace' source written by
* mromarkhan ("Peace be unto you").
*
* #author Omar Khan
* #author Andrew Thompson
* #version 2004-05-31
*/
public class JArabicInUnicode extends JFrame {
/**
* Unicode constant used in this example.
*/
public final static String ALEF = "\u0627",
LAM = "\u0644",
SEEN = "\u0633",
MEEM = "\u0645",
AIN = "\u0639",
YEH = "\u064A",
KAF = "\u0643",
HEH = "\u0647";
/**
* An array of the letters that spell 'Aslam Alykm'.
*/
String text[] = {
ALEF, //a
LAM + SEEN, //s
LAM, //l
ALEF, //a
MEEM, //m
" ",
AIN, //a
LAM, //l
YEH, //y
KAF, //k
MEEM //m
};
/**
* Displays the letters of the phrase 'Aslam Alykm' as well as the words
* spelt out letter by letter.
*/
public JArabicInUnicode() {
super("Peace be upon you");
JTextArea textwod = new JTextArea(7, 10);
textwod.setEditable(false);
textwod.setFont(new Font("null", Font.PLAIN, 22));
String EOL = System.getProperty("line.separator");
// write the phrase to the text area
textwod.append(getCharacters() + EOL);
// now spell it, one letter at a time
for (int ii = 0; ii <= text.length; ii++) {
textwod.append(getCharacters(ii) + EOL);
}
textwod.setCaretPosition(0);
getContentPane().add(
new JScrollPane(textwod,
ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED,
ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED),
BorderLayout.CENTER);
pack();
setMinimumSize(getPreferredSize());
try {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocationRelativeTo(null);
} catch (Exception e) {
} // allows to run under 1.2
}
/**
* Get a string of the entire phrase.
*/
String getCharacters() {
return getCharacters(text.length);
}
/**
* Get a string of the 1st 'num' characters of the phrase.
*/
String getCharacters(int num) {
StringBuffer sb = new StringBuffer();
for (int ii = 1; ii < num; ii++) {
sb.append(text[ii]);
}
return sb.toString();
}
/**
* Instantiate an ArabicInUnicode frame.
*/
public static void main(String[] args) {
Runnable r = new Runnable() {
#Override
public void run() {
new JArabicInUnicode().setVisible(true);
}
};
// Swing GUIs should be created and updated on the EDT
// http://docs.oracle.com/javase/tutorial/uiswing/concurrency/initial.html
SwingUtilities.invokeLater(r);
}
}

JProgressbar: how to change colour based on progress?

Is it possible to be able to change the bar colour depending on the value of the progress? I tried the following but it doesn't work:
percentUsed = (int)(((float) used / (float) max) * BAR_PERCENTAGE);
if (percentUsed >= ORANGE_THRESHOLD && percentUsed < RED_THRESHOLD) {
if (!m_orangeIndicator) {
LOG.warn(String.format("Memory usage exceeds %d percent.", ORANGE_THRESHOLD));
m_orangeIndicator = true;
}
colour = Color.ORANGE;
m_redIndicator = false;
}
else if (percentUsed >= RED_THRESHOLD) {
if (!m_redIndicator) {
LOG.warn(String.format("Memory usage exceeds %d percent.", RED_THRESHOLD));
m_orangeIndicator = true;
m_redIndicator = true;
}
colour = Color.RED;
}
else {
m_orangeIndicator = false;
m_redIndicator = false;
colour = Color.GREEN;
}
m_memUsageBar.setForeground(colour);
m_memUsageBar.setValue(percentUsed);
m_memUsageBar.updateUI();
I am guessing it is not a trivial thing to do because JProgressbar is not meant to be used that way... But is it possible or are there alternatives?

This sample was inspired from:
http://harmoniccode.blogspot.jp/2011/05/varying-gradients.html
http://java-swing-tips.blogspot.jp/2011/06/gradient-translucent-track-jslider.html
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.awt.image.*;
import java.beans.*;
import javax.swing.*;
import javax.swing.plaf.basic.*;
import javax.swing.event.*;
public class GradientPalletProgressBarDemo {
public JComponent makeUI() {
final JProgressBar progressBar = new JProgressBar();
progressBar.setOpaque(false);
progressBar.setUI(new GradientPalletProgressBarUI());
JPanel p = new JPanel();
p.add(progressBar);
p.add(new JButton(new AbstractAction("Start") {
#Override public void actionPerformed(ActionEvent e) {
SwingWorker<Void,Void> worker = new SwingWorker<Void,Void>() {
#Override public Void doInBackground() {
int current = 0, lengthOfTask = 100;
while(current<=lengthOfTask && !isCancelled()) {
try { // dummy task
Thread.sleep(50);
} catch(InterruptedException ie) {
return null;
}
setProgress(100 * current / lengthOfTask);
current++;
}
return null;
}
};
worker.addPropertyChangeListener(new ProgressListener(progressBar));
worker.execute();
}
}));
return p;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override public void run() {
createAndShowGUI();
}
});
}
public static void createAndShowGUI() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.getContentPane().add(new GradientPalletProgressBarDemo().makeUI());
frame.setSize(320, 240);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
}
class ProgressListener implements PropertyChangeListener {
private final JProgressBar progressBar;
ProgressListener(JProgressBar progressBar) {
this.progressBar = progressBar;
this.progressBar.setValue(0);
}
#Override public void propertyChange(PropertyChangeEvent evt) {
String strPropertyName = evt.getPropertyName();
if("progress".equals(strPropertyName)) {
progressBar.setIndeterminate(false);
int progress = (Integer)evt.getNewValue();
progressBar.setValue(progress);
}
}
}
class GradientPalletProgressBarUI extends BasicProgressBarUI {
private final int[] pallet;
public GradientPalletProgressBarUI() {
super();
this.pallet = makeGradientPallet();
}
private static int[] makeGradientPallet() {
BufferedImage image = new BufferedImage(100, 1, BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = image.createGraphics();
Point2D start = new Point2D.Float(0f, 0f);
Point2D end = new Point2D.Float(99f, 0f);
float[] dist = {0.0f, 0.5f, 1.0f};
Color[] colors = { Color.RED, Color.YELLOW, Color.GREEN };
g2.setPaint(new LinearGradientPaint(start, end, dist, colors));
g2.fillRect(0, 0, 100, 1);
g2.dispose();
int width = image.getWidth(null);
int[] pallet = new int[width];
PixelGrabber pg = new PixelGrabber(image, 0, 0, width, 1, pallet, 0, width);
try {
pg.grabPixels();
} catch(Exception e) {
e.printStackTrace();
}
return pallet;
}
private static Color getColorFromPallet(int[] pallet, float x) {
if(x < 0.0 || x > 1.0) {
throw new IllegalArgumentException("Parameter outside of expected range");
}
int i = (int)(pallet.length * x);
int max = pallet.length-1;
int index = i<0?0:i>max?max:i;
int pix = pallet[index] & 0x00ffffff | (0x64 << 24);
return new Color(pix, true);
}
#Override public void paintDeterminate(Graphics g, JComponent c) {
if (!(g instanceof Graphics2D)) {
return;
}
Insets b = progressBar.getInsets(); // area for border
int barRectWidth = progressBar.getWidth() - (b.right + b.left);
int barRectHeight = progressBar.getHeight() - (b.top + b.bottom);
if (barRectWidth <= 0 || barRectHeight <= 0) {
return;
}
int cellLength = getCellLength();
int cellSpacing = getCellSpacing();
// amount of progress to draw
int amountFull = getAmountFull(b, barRectWidth, barRectHeight);
if(progressBar.getOrientation() == JProgressBar.HORIZONTAL) {
// draw the cells
float x = amountFull / (float)barRectWidth;
g.setColor(getColorFromPallet(pallet, x));
g.fillRect(b.left, b.top, amountFull, barRectHeight);
} else { // VERTICAL
//...
}
// Deal with possible text painting
if(progressBar.isStringPainted()) {
paintString(g, b.left, b.top, barRectWidth, barRectHeight, amountFull, b);
}
}
}

You can do either of this way:
UIManager.put("ProgressBar.background", Color.BLACK); //colour of the background
UIManager.put("ProgressBar.foreground", Color.RED); //colour of progress bar
UIManager.put("ProgressBar.selectionBackground",Color.YELLOW); //colour of percentage counter on black background
UIManager.put("ProgressBar.selectionForeground",Color.BLUE); //colour of precentage counter on red background
There is a thread here.
Setting the colors of a JProgressBar text
There is a sample demo here at this link as well.
how to change color progressbar

As you noticed, is value-dependent "progress" painting not supported. Theoretically, setting the foregound of the progressBar instance dynamically (that is depending on value) is the way to go.
But: the details of progressBar painting are highly LAF dependent
in simple LAFs (like Metal) setting the foreground is fine
in fully skinnable LAFs (like synth-based LAF) that support per-instance skinning (f.i. Nimbus) you can try to provide a Painter which uses the foreground
in not-skinnable LAFs there is no way (except overriding the concrete LAF and try to hook into the painting code)
Some snippet:
final JProgressBar bar = new JProgressBar();
// used for Nimbus (beware: just a proof-of-concept - this looks extremely ugly!)
Painter p = new Painter() {
#Override
public void paint(Graphics2D g, Object object, int width, int height) {
JProgressBar bar = (JProgressBar) object;
g.setColor(bar.getForeground());
g.fillRect(0, 0, width, height);
}
};
// install custom painter on the bar
UIDefaults properties = new UIDefaults();
properties.put("ProgressBar[Enabled].foregroundPainter", p);
bar.putClientProperty("Nimbus.Overrides", properties);
// simulate progress
Action action = new AbstractAction("timer") {
#Override
public void actionPerformed(ActionEvent e) {
bar.setValue(bar.getValue() + 1);
// change foreground value-dependent
if (bar.getValue() > 10) {
bar.setForeground(Color.RED);
}
}
};
Timer timer = new Timer(100, action);
timer.start();

Thanks for the help but by trial and error I found a way to get the colour changing with using my existing code.
I am not sure if its the quirk of JPrgressbar but if call do the following call the foreground bar colour can be changed dynamically with minimal rework:
progressBar.setStringPainted(true);

Change background and font color of jpanel on button click

I want to change Background color of Jpanel and its font on button click.
Can anyone tell me what i am doing wrong?
Can I set JPanel background transparent?if yes How?
On button click test4.action method is called where i need to change Jpanel background color?
Here is the code:
import java.applet.*;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.awt.event.*;
import javax.swing.*;
public class test3 extends Applet {
JPanel c;
JScrollPane s;
Button connect;
Panel controls;
Color back, fore;
public void init() {
back = Color.black;
fore = Color.white;
setBackground(Color.darkGray);
setLayout(new BorderLayout());
s = new JScrollPane(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS, JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
//s.setSize(100, 100);
add("Center", s);
c = new myCanvas11(this);
s.setOpaque(false);
s.setViewportView(c);
//s.add(c);
c.setSize(1000, 16000);
add("North", controls = new Panel());
controls.setLayout(new FlowLayout());
controls.add(connect = new Button("Change Color"));
}
public void start() {
// s.setScrollPosition(100, 100);
}
public boolean action(Event e, Object arg) {
back = Color.magenta;
fore = Color.blue;
//setBackground(back);
//invalidate();
//repaint();
c.setBackground(back);
c.repaint();
//s.getViewport().setBackground(back);
// s.getViewport().repaint();
//c.repaint();
c.setFocusable(true);
return true;
}
}
class myCanvas11 extends JPanel implements KeyListener {
Image buffImage;
Graphics offscreen;
boolean initDone = false;
int chw, chh; // size of a char (in pixels)
int chd; // offset of char from baseline
int width, height; // size of applet (in pixels)
int w, h; // size of applet (in chars)
Font fn;
Graphics gr;
int nh, nw;
test3 owner;
static int counter = 0;
myCanvas11(test3 t) {
super();
owner = t;
nh = 16000;
nw = 1000;
this.setOpaque(true);
this.setFocusable(true);
addKeyListener(this);
}
public void reshape(int nx, int ny, int nw1, int nh1) {
if (nw1 != width || nh1 != height) {
width = nw;
height = nh;
gr = getGraphics();
fn = new Font("Courier", Font.PLAIN, 11);
if (fn != null) {
gr.setFont(fn);
}
FontMetrics fnm = gr.getFontMetrics();
chw = fnm.getMaxAdvance();
chh = fnm.getHeight();
chd = fnm.getDescent();
// kludge for Windows NT and others which have too big widths
if (chw + 1 >= chh) {
chw = (chw + 1) / 2;
}
// work out size of drawing area
h = nh / chh;
w = nw / chw;
buffImage = this.createImage(nw, nh);
offscreen = buffImage.getGraphics();
//offscreen.setColor(Color.black);
//offscreen.fillRect(0, 0, nw, nh);
offscreen.setColor(Color.blue);
offscreen.setFont(fn);
if (initDone) {
offscreen.drawString("Hello World!", 0, 50);
} else {
offscreen.drawString("khushbu", 2, 50);
}
initDone = true;
offscreen.drawImage(buffImage, 0, 0, this);
}
super.reshape(nx, ny, nw, nh);
}
public void paint(Graphics g) {
// if (!initDone)
// initpaint(g);
// else
g.drawImage(buffImage, 0, 0, this);
//g.drawImage(buffImage, 0, 0, owner.back, this);
}
public void update(Graphics g) {
g.drawImage(buffImage, 0, 0, this);
super.update(g);
//g.drawImage(buffImage, 0, 0, owner.back, this);
}
public void initpaint(Graphics g) {
try {
nh = getHeight();
nw = getWidth();
gr = getGraphics();
fn = new Font("Courier", Font.PLAIN, 11);
if (fn != null) {
gr.setFont(fn);
}
FontMetrics fnm = gr.getFontMetrics();
chw = fnm.getMaxAdvance();
chh = fnm.getHeight();
chd = fnm.getDescent();
// kludge for Windows NT and others which have too big widths
if (chw + 1 >= chh) {
chw = (chw + 1) / 2;
}
// work out size of drawing area
h = nh / chh;
w = nw / chw;
buffImage = this.createImage(nw, nh);
offscreen = buffImage.getGraphics();
//offscreen.setColor(Color.black);
//offscreen.fillRect(0, 0, nw, nh);
offscreen.setColor(Color.white);
offscreen.setFont(fn);
if (initDone) {
offscreen.drawString("Hello World!", 0, 50);
} else {
offscreen.drawString("khushbu", 2, 50);
}
initDone = true;
g.drawImage(buffImage, 0, 0, this);
} catch (Exception e) {
e.printStackTrace();
}
}
/** Handle the key typed event from the text field. */
public void keyTyped(KeyEvent e) {
}
/** Handle the key pressed event from the text field. */
public void keyPressed(KeyEvent e) {
String s;
offscreen.setColor(owner.fore);
offscreen.setFont(fn);
for (int i = counter; i < counter + 25; ++i) {
s = Integer.toString(i);
offscreen.drawString(s, 3, i * chh);
offscreen.drawLine(10, i * chh, 160, i * chh);
}
//owner.s.setScrollPosition(0, counter * 16);
counter = counter + 25;
repaint();
}
/** Handle the key released event from the text field. */
public void keyReleased(KeyEvent e) {
}
public boolean keyDown(Event e, int k) {
String s;
offscreen.setColor(owner.fore);
offscreen.setFont(fn);
for (int i = counter; i < counter + 25; ++i) {
s = Integer.toString(i);
offscreen.drawString(s, 3, i * chh);
offscreen.drawLine(10, i * chh, 160, i * chh);
}
//owner.s.setScrollPosition(0, counter * 16);
counter = counter + 25;
repaint();
return true;
}
}

Can I set JPanel background transparent?if yes How?
Yes, just call setOpaque(false); on that JPanel. On the contrary, if you want the background to be painted, call setOpaque(true); on that panel.
Additional remarks:
public boolean action(Event e, Object arg) is Deprecated. Add the appropriate listeners instead.
Follow Java coding conventions and use an Uppercase letter for the first character of a class
You should almost never call getGraphics(); on a Component
Don't override public void paint(Graphics g) but protected void paintComponent(Graphics g). Don't forget to call super.paintComponent if you want the background to be painted
Why do you override reshape?
Why do you create an internal buffer? Swing already has built-in double buffering and they do a much better job.
If you overrode already paint() why do you also override update()? You are performing the same job twice.
Remove that gr class variable, it does not make any sense. When you use Graphics object, use the one provided as a parameter of the paintComponent method but don't keep a reference to it, as it will be disposed later.
counter does not need to be static. Try to avoid static as much as possible.
Try to avoid so much coupling between your classes. It makes your code harder to maintain and less predictable.
Next time, post an SSCCE with something else than an Applet (a JFrame, for example) unless the problem you are having really requires an Applet to be reproduced.