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Java Swing: how to react to clicking a custom JComponent?

I'm trying to make a game with ducks, the ducks are moving on the screen and I can't get a mouse click on them. I'm obviously doing something wrong because despite setting a MouseListener, its methods are not called. This is my code, I omitted getters and the DuckGame class, which is only generating ducks.
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
public class DuckGameScreen extends JPanel {
private int initialDuckNum = 7;
private final int INTERVAL = 25;
private final int INTERVAL_BTWN_DUCKS = 1000;
private Timer duckTimer;
private int ducksStarted = 0;
private DuckGame duckGame;
public DuckGameScreen() {
setBackground(Color.cyan);
askAboutDifficulty();
startTimer();
startGame();
startDifficultyIncrease();
}
private void startGame() {
duckGame = new DuckGame(initialDuckNum);
startDucks();
addDuckListeners();
}
private void addDuckListeners() {
for (Duck duck : duckGame.getDucks()) {
duck.addMouseListener(new MouseListener() {
#Override
public void mouseClicked(MouseEvent e) {}
#Override
public void mousePressed(MouseEvent e) {
System.out.println("Duck clicked");}
#Override
public void mouseReleased(MouseEvent e) {}
#Override
public void mouseEntered(MouseEvent e) {}
#Override
public void mouseExited(MouseEvent e) {}
});
}
}
#Override
public void paint(Graphics g) {
super.paint(g);
drawDucks(g);
Toolkit.getDefaultToolkit().sync();
}
private void animateDuck(Duck duck) {
new Thread() {
#Override
public void run() {
super.run();
while (!duck.isDuckStopped()) {
try {
Thread.sleep(INTERVAL);
duck.move();
if (duck.getX() - duck.getWidth() >= Toolkit.getDefaultToolkit().getScreenSize().width) {
duck.resetPosition();
}
repaint();
} catch (InterruptedException e) {
e.printStackTrace();
duck.stop();
break;
}
}
}
}
.start();
}
private void drawDucks(Graphics g) {
for (Duck duck : duckGame.getDucks()) {
duck.paintComponent(g);
}
}
}
And my Duck class:
public class Duck extends JComponent {
private final static int INIT_X = -100;
private int x = INIT_X;
private int y = 100;
private int width = 0;
private int height = 0;
private Image image = null;
private boolean isDuckStopped = false;
private final int STEP = 5;
public Duck() {
initRandomPosition();
loadImage();
setVisible(true);
setBounds(x, y, width, height);
}
private void initRandomPosition() {
y = getRandomY();
}
public void move() {
x += STEP;
}
private void loadImage() {
ImageIcon imageIcon = new ImageIcon(getFilePath(Images.DUCK.getFileName()));
Dimension newDimension = Utils.getScaledDimension(100, 100, imageIcon.getIconWidth(), imageIcon.getIconHeight());
image = imageIcon.getImage().getScaledInstance(newDimension.width, newDimension.height, Image.SCALE_DEFAULT);
width = image.getWidth(null);
height = image.getHeight(null);
}
#Override
public void paintComponent(Graphics g) {
super.paintComponents(g);
drawDuck(g);
Toolkit.getDefaultToolkit().sync();
}
private void drawDuck(Graphics g) {
Graphics2D g2D = (Graphics2D) g;
g2D.drawImage(image, x, y, this);
setBounds(x, y, width, height);
}
public void stop() {
isDuckStopped = true;
setVisible(false);
}
public void resetPosition() {
x = INIT_X;
y = getRandomY();
}
}

How can I make my game fall when off the platform I made?

I want it so when my player goes off the platform, (in checkCollision() method PlatformerPanel class) it will fall and then do something when gone off the screen, i haven't set up an end game screen yet but that's what I'm planning to do. Anyway, the problem is that it goes way too fast for some reason and falls too early, and also when an arrow key is pressed while its falling it will go back up to the platform.
Please try to help me overcome this or think of a new, easy to understand, way to do this/make this work the way i am planning.
EDIT 1:
I fixed the thing where it falls too early so don't worry about that
```
public class PlatformerMain {
public static void main(String[] args) {
PlatformerGameFrame platformerGame = new PlatformerGameFrame();
}
}
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
public class PlatformerGameFrame extends JFrame{
PlatformerGamePanel panel;
PlatformerGameFrame() {
panel = new PlatformerGamePanel();
this.add(panel);
this.setTitle("Platformer Game");
this.setResizable(false);
this.setDefaultCloseOperation(DISPOSE_ON_CLOSE);
this.pack();
this.setVisible(true);
this.setLocationRelativeTo(null);
this.getContentPane().setBackground(new Color(0,0,0));
}
}
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
public class PlatformerGamePanel extends JPanel implements Runnable{
PlatformerPlayer player1;
PlatformerMap map1;
static final int SCREEN_WIDTH = 1000;
static final int SCREEN_HEIGHT = 600;
static final int PLAYER_WIDTH = 50;
static final int PLAYER_HEIGHT = 60;
static final Dimension SCREEN_SIZE = new Dimension(SCREEN_WIDTH,SCREEN_HEIGHT);
static boolean falling = false;
Image backgroundImage;
Thread gameThread;
Image image;
Graphics graphics;
PlatformerMap map;
public PlatformerGamePanel() {
java.net.URL imgIcon = Main.class.getResource(
"/Resources/spaceImage.jpg");
backgroundImage = new ImageIcon(imgIcon).getImage();
newPlayer();
newMap();
this.setFocusable(true);
this.addKeyListener(new KeyListener() {
#Override
public void keyTyped(KeyEvent e) {}
#Override
public void keyPressed(KeyEvent e) {
player1.KeyPressed(e);
}
#Override
public void keyReleased(KeyEvent e) {
player1.KeyReleased(e);
}
});
this.setPreferredSize(SCREEN_SIZE);
this.setOpaque(true);
gameThread = new Thread(this);
gameThread.start();
}
public void paint(Graphics g) {
image = createImage(getWidth(),getHeight());
graphics = image.getGraphics();
draw(graphics);
g.drawImage(image, 0,0, null);
}
public void draw(Graphics g) {
Graphics2D g2D = (Graphics2D) g;
g2D.drawImage(backgroundImage, 0,0, null);
player1.paint(g);
map.paint(g);
}
public void newPlayer() {
player1 = new PlatformerPlayer((SCREEN_WIDTH/2)-(PLAYER_WIDTH/2), (SCREEN_HEIGHT/2)-(PLAYER_WIDTH/2), PLAYER_WIDTH, PLAYER_HEIGHT);
}
public void newMap() {
map = new PlatformerMap();
}
public void checkCollision() {
if(player1.x > SCREEN_WIDTH-PLAYER_WIDTH) {
player1.x = SCREEN_WIDTH-PLAYER_WIDTH;
}
else if(player1.x < 0) {
player1.x = 0;
}
if(!(player1.x >map.PLATFORM_WIDTH)) {
if(player1.y > SCREEN_HEIGHT-250) {
player1.y = SCREEN_HEIGHT-250;
}
} else if(player1.x > map.PLATFORM_WIDTH) {
gravity();
}
}
public void falling() {
}
public void gravity() {
player1.gravity();
}
public void move() {
player1.move();
}
public void run() {
long lastTime = System.nanoTime();
double amountOfTicks = 120.0;
double ns = 1000000000 / amountOfTicks;
double delta = 0;
while(true) {
long now = System.nanoTime();
delta += (now - lastTime)/ns;
lastTime = now;
if(delta >= 1) {
move();
checkCollision();
gravity();
repaint();
delta--;
}
}
}
}
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
public class PlatformerPlayer extends Rectangle {
/*static int playerPosX = 100;
static int playerPosY = 100;*/
static double velocityY = 0;
static double velocityX = 0;
static int vertical_position;
static final int TERMINAL_VELOCITY = 200;
static final int PLAYER_WIDTH = 50;
static final int PLAYER_HEIGHT = 50;
static int speed = 2;
protected boolean falling = true;
protected boolean jumping = false;
double gravity = 0.05;
public PlatformerPlayer(int x, int y, int PLAYERWIDTH, int PLAYERHEIGHT) {
super(x,y,PLAYERWIDTH,PLAYERHEIGHT);
}
public void KeyPressed(KeyEvent e) {
if(e.getKeyCode()==KeyEvent.VK_LEFT) {
setXDirection(-speed);
move();
}
else if(e.getKeyCode()==KeyEvent.VK_RIGHT) {
setXDirection(speed);
move();
}
}
public void KeyReleased(KeyEvent e) {
if(e.getKeyCode()==KeyEvent.VK_LEFT) {
setXDirection(0);
move();
}
else if(e.getKeyCode()==KeyEvent.VK_RIGHT) {
setXDirection(0);
move();
}
}
public void paint(Graphics g) {
Graphics2D g2D = (Graphics2D) g;
g2D.setColor(Color.red);
g2D.fillRect(x, y, PLAYER_WIDTH, PLAYER_HEIGHT);
}
public void setYDirection(int YDirection) {
velocityY = YDirection;
}
public void setXDirection(int XDirection) {
if(speed > 10) {
speed = 10;
}
velocityX = XDirection;
}
public void move() {
y += velocityY;
x += velocityX;
}
public void gravity() {
velocityY += gravity;
if (velocityY > TERMINAL_VELOCITY)
{
velocityY = TERMINAL_VELOCITY;
}
vertical_position -= velocityY;
}
}
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
public class PlatformerMap extends Rectangle {
int PLATFORM_WIDTH = 600;
int PLATFORM_HEIGHT = 150;
public PlatformerMap() {
}
public void paint(Graphics g) {
Graphics2D g2D = (Graphics2D) g;
g2D.setColor(Color.gray);
g2D.fillRect(100,400,PLATFORM_WIDTH,PLATFORM_HEIGHT);
}
}

Flickering While Resizing Transparent JWindow

I'm trying to make a transparent window with Java Swing, and I have created the window. Problem is when I resize the window, it flickers. I tried changing the background to an opaque color instead. That fixed the problem, But I want the window to be transparent. I have also tried
Toolkit.getDefaultToolkit().setDynamicLayout(true);,
Toolkit.getDefaultToolkit().getDesktopProperty("awt.dynamicLayoutSupported");,
System.setProperty("sun.awt.noerasebackground", "true");,
But with no avail. I've tried JWindow.setBounds instead of JWindow.setSize, but that also had no effect.
Here is the code I use to produce the window
import java.awt.Color;
import java.awt.Graphics;
import java.awt.MouseInfo;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.JPanel;
import javax.swing.JWindow;
public class GlassWindow extends JPanel {
// RIGHT CLICK TO CLOSE
private static final long serialVersionUID = 1L;
private JWindow jwindow = new JWindow();
private boolean programCalledRender, shouldClose;
private int edges = 8;
private Color background = new Color(255, 100, 0, 100);
public GlassWindow() {
int width = 1000, height = 750;
this.setOpaque(false);
this.setSize(width, height);
jwindow.setSize(width, height);
jwindow.setBackground(new Color(0, 0, 0, 0));
jwindow.setContentPane(this);
jwindow.setLocationRelativeTo(null);
jwindow.setVisible(true);
jwindow.addMouseListener(new MouseListener() {
public void mouseClicked(MouseEvent e) {
if(e.getButton() == MouseEvent.BUTTON3) System.exit(0);
}
public void mouseEntered(MouseEvent e) {}
public void mouseExited(MouseEvent e) {}
public void mousePressed(MouseEvent e) {}
public void mouseReleased(MouseEvent e) {}
});
new Thread(() -> run()).start();
}
public void render() {
programCalledRender = true;
this.repaint();
}
private void run() {
int setTPS = 20, setFPS = 60;
long lastTime = System.nanoTime();
double delta = 0, frameDelta = 0;
while(true) {
if(shouldClose) break;
long now = System.nanoTime();
delta += (now-lastTime)/(1000000000/(double)setTPS);
frameDelta += (now-lastTime)/(1000000000/(double)setFPS);
lastTime = now;
while(delta > 0) {
tick();
delta--;
}
while(frameDelta > 0) {
render();
frameDelta--;
}
}
}
private void tick() {
}
#Override
public void paintComponent(Graphics g) {
if(!programCalledRender) return;
super.paintComponent(g);
int newWidth = MouseInfo.getPointerInfo().getLocation().x+20-jwindow.getX();
if(newWidth != jwindow.getWidth()) {
jwindow.setSize(newWidth, jwindow.getHeight());
}
if(background != null) {
g.setColor(background);
g.fillRect(edges, edges, jwindow.getWidth()-edges*2, jwindow.getHeight()-edges*2);
}
g.setColor(new Color(0, 0, 0, 100));
for(int i = 0; i <= edges; i++) {
g.drawRect(i, i, jwindow.getWidth()-i*2, jwindow.getHeight()-i*2);
}
}
public static void main(String[] args) {
new GlassWindow();
}
}
How can I prevent flickering when the JWindow is being resized?
Any help is appreciated.

As suggested by #camickr I should not resize the window in the render method.
So to stop the flickering I remove
int newWidth = MouseInfo.getPointerInfo().getLocation().x+20-jwindow.getX();
if(newWidth != jwindow.getWidth()) {
jwindow.setSize(newWidth, jwindow.getHeight());
}
from the paintComponent(Graphics g) method. And add
jwindow.addMouseMotionListener(new MouseMotionListener() {
public void mouseDragged(MouseEvent e) {}
public void mouseMoved(MouseEvent e) {
int newWidth = MouseInfo.getPointerInfo().getLocation().x+20-jwindow.getX();
if(newWidth != jwindow.getWidth()) {
jwindow.setSize(newWidth, jwindow.getHeight());
}
}
});
to the constructor GlassWindow().

Nothing renders onto the screen even though I call my render method

Why my tick(); method being called, but not my render(); method is the question here.
So, I have a class that holds my updating and my rendering here:
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
public class MapI extends Map {
int players = 8, islands = 8;
private int dimAm, irAm, golAm, emAm;
#Override
public void tick() {
while(irAm < 48) {
tickIr();
}
while(dimAm < 4) {
tickDim();
}
}
public void tickDim() {
try {
Thread.sleep(20000);
} catch(InterruptedException e) {
e.printStackTrace();
}
dimAm += 1;
System.out.println(dimAm + " diamonds");
}
public void tickIr() {
try {
Thread.sleep(2000);
} catch(InterruptedException e) {
e.printStackTrace();
}
irAm += 1;
System.out.println(irAm + " iron");
}
#Override
public void render(Graphics g) {
g.setFont(new Font("Arial", Font.BOLD, 12));
g.setColor(Color.BLACK);
g.fillRect(30, 10, 50, 50); // dim gen(s)
g.drawString(dimAm + "", 41, 29);
g.setColor(Color.CYAN);
g.fillRect(40, 20, 30, 30);
g.setColor(Color.YELLOW);
g.fillRect(30, 100, 50, 50); // yellow base
}
}
Here's the Map class:
import java.awt.Graphics;
public abstract class Map {
protected int players, islands;
public abstract void tick();
public abstract void render(Graphics g);
}
What is happening is, when my run() method in my Game class is called, it has a while(running), and inside that loop is where I specify to render and update:
public void run(){
init();
while(running){
render();
tick();
}
stop();
}
public synchronized void start(){
if(running)
return;
running = true;
thread = new Thread(this);
thread.start();
}
public synchronized void stop(){
if(!running)
return;
running = false;
try {
thread.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
With this, I should both render and update, but, as of right now, all that goes on is updates. I think that my problem might come with
#Override
public void tick() {
while(irAm < 48) {
tickIr();
}
while(dimAm < 4) {
tickDim();
}
}
, which is inside of MapI. What I think is happening is nothing else will render until none of these loops are still running, but then again, I don't know how to bypass that.
My GameAspect class that houses the render method is here:
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
import blaze.game.gfx.Assets;
import blaze.game.maps.MapI;
public class GameAspect implements Runnable {
private Display display;
public int width, height;
public String title;
private boolean running = false;
private Thread thread;
private BufferStrategy bs;
private Graphics g;
private MapI map1;
public GameAspect(String title, int width, int height){
this.width = width;
this.height = height;
this.title = title;
map1 = new MapI();
}
private void init(){
display = new Display(title, width, height);
Assets.init();
}
private void tick(){
map1.tick();
}
private void render(){
bs = display.getCanvas().getBufferStrategy();
if(bs == null){
display.getCanvas().createBufferStrategy(3);
return;
}
g = bs.getDrawGraphics();
//Clear Screen
g.clearRect(0, 0, width, height);
//Draw Here!
map1.render(g);
//End Drawing!
bs.show();
g.dispose();
}
public void run(){
init();
while(running){
render();
tick();
}
stop();
}
public synchronized void start(){
if(running)
return;
running = true;
thread = new Thread(this);
thread.start();
}
public synchronized void stop(){
if(!running)
return;
running = false;
try {
thread.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}

Java animation does not refresh properly and uses too much CPU

I have a problem with a simple Java game I am creating right now. I want a dot (a car) to be movable across the game screen, but instead of this all I can see on the screen is the long "snake" created by the dot moved by me:
Other problem is that activity manager on my Mac shows that the game uses huge amount of CPU power - my laptop gets very hot very fast. I suspect that there is something wrong with my game loop, but since now I haven't found any solution:
BoardPanel.java:
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.awt.event.*;
import javax.swing.*;
#SuppressWarnings("serial")
public class BoardPanel extends JPanel implements KeyListener, Runnable {
public static final int WIDTH = 600;
public static final int HEIGHT = 600;
private Thread thread;
private boolean running;
private BufferedImage image;
private Graphics2D g;
private int FPS = 30;
private int targetTime = 1000/FPS;
private Map map;
private Car car;
public BoardPanel() {
super();
setPreferredSize(new Dimension(WIDTH, HEIGHT));
setFocusable(true);
requestFocus();
}
public void addNotify() {
super.addNotify();
if(thread == null) {
thread = new Thread(this);
thread.start();
}
addKeyListener(this);
}
public void run() {
init();
long startTime;
long reTime;
long waitTime;
while (running) {
startTime = System.nanoTime();
update();
render();
draw();
reTime = System.nanoTime() - startTime;
waitTime = targetTime - reTime;
try {
Thread.sleep(waitTime);
}
catch(Exception e) {
}
}
}
private void init() {
running = true;
image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);
g = (Graphics2D) image.getGraphics();
map = new Map();
car = new Car(map);
car.setxpos(50);
car.setypos(50);
}
private void update() {
map.update();
car.update();
}
private void render() {
map.draw(g);
car.draw(g);
}
private void draw() {
Graphics g2 = getGraphics();
g2.drawImage(image, 0, 0, null);
g2.dispose();
}
public void keyTyped(KeyEvent key) {
}
public void keyPressed(KeyEvent key) {
int code = key.getKeyCode();
if(code == KeyEvent.VK_LEFT) {
car.setLeft(true);
}
if(code == KeyEvent.VK_RIGHT) {
car.setRight(true);
}
if(code == KeyEvent.VK_UP) {
car.setUp(true);
}
if(code == KeyEvent.VK_DOWN) {
car.setDown(true);
}
}
public void keyReleased(KeyEvent key) {
int code = key.getKeyCode();
if(code == KeyEvent.VK_LEFT) {
car.setLeft(false);
}
if(code == KeyEvent.VK_RIGHT) {
car.setRight(false);
}
if(code == KeyEvent.VK_UP) {
car.setUp(false);
}
if(code == KeyEvent.VK_DOWN) {
car.setDown(false);
}
}
}
Car.java
import java.awt.*;
public class Car {
private double xpos;
private double ypos;
//private int xsize;
//private int ysize;
private boolean left;
private boolean right;
private boolean up;
private boolean down;
private Map map;
public Car(Map m) {
map = m;
}
public void setxpos(int i) {
xpos = i;
}
public void setypos(int i) {
ypos = i;
}
public void setLeft (boolean b) {
left = b;
}
public void setRight (boolean b) {
right = b;
}
public void setUp (boolean b) {
up = b;
}
public void setDown (boolean b) {
down = b;
}
public void update() {
if(left) {
xpos--;
}
if(right) {
xpos++;
}
if(up) {
ypos--;
}
if(down) {
ypos++;
}
}
public void draw(Graphics2D g) {
int mx = map.getx();
int my = map.gety();
g.setColor(Color.BLUE);
g.fillOval((int)(mx+xpos-20/2), (int)(my+ypos-20/2), 20, 20);
}
}
Map.java (I haven't created map yet, right now only want the dot to move properly)
import java.awt.*;
public class Map {
public int x;
public int y;
public int getx() {
return x;
}
public int gety() {
return y;
}
public void setx(int i) {
x = i;
}
public void sety(int i ) {
y = i;
}
public void update() {
}
public void draw(Graphics2D g) {
}
}
RacerMain.java
import javax.swing.JFrame;
public class RacerMain {
public static void main (String[]args) {
//MainFrame mf = new MainFrame();
JFrame mf = new JFrame("Racer");
mf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mf.setContentPane(new BoardPanel());;
mf.pack();
mf.setVisible(true);
}
}
Many thanks for your help!!!

In addition to what camickr said: Be careful with your usage of the Graphics. A rule of thumb:
Never call getGraphics on a Component!
Additionally, you are never disposing the Graphics that you are fetching from the BufferedImage. You are instead disposing the Graphics that you obtained from the Component, which may be even worse than fetching it in the first place!
I wonder why you are overriding the addNotify method. You should not implement any functionality based on averriding this method....
So you should change the respecive parts of your BoardPanel class roughly as follows:
public class BoardPanel extends JPanel implements KeyListener, Runnable {
...
// private Graphics2D g; // Don't store this here
public BoardPanel() {
...
// Create the thread here instead of in the "addNotify" method!
if(thread == null) {
thread = new Thread(this);
thread.start();
}
addKeyListener(this);
}
public void run() {
...
while (running) {
...
//draw(); // Don't call this method
repaint(); // Trigger a repaint instead!
}
}
private void render() {
Graphics2D g = image.createGraphics();
// Clear the background (see camickrs answer)
g.setColor(Color.BLACK);
g.fillRect(0,0,image.getWidth(),image.getHeight());
try
{
map.draw(g);
car.draw(g);
}
finally
{
g.dispose(); // Dispose the Graphics after it has been used
}
}
/** Don't call "getGraphics" on a component!
private void draw() {
Graphics g2 = getGraphics();
g2.drawImage(image, 0, 0, null);
g2.dispose();
}
*/
// Override the paintComponent method instead:
#Override
protected void paintComponent(Graphics g)
{
super.paintComponent(g);
g.drawImage(image,0,0,null);
}

In your draw() method you need to clear the BufferedImages background before your invoke the fillOval method. Something like:
g.setColor( Color.BLACK );
g.fillRect(...);
g.setColor( Color.BLUE );
g.fillOval(...);
Print out your "waitTime" to make sure you are waiting a reasonable time.