Develop Reference

Is there a way to make a 2nd click change the result?

I'm trying to make it when you click the cameraButton, the graphics show, but when clicked again, it closes.
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
int camButtonWidth = 500;
int camButtonHeight = 33;
int camButtonX = (width - camButtonWidth) / 2;
int camButtonY = (height - camButtonHeight) - 5;
int camWidth = width - 50;
int camHeight = (height - (camButtonHeight * 2)) - 10;
int camX = (width - camWidth) / 2;
int camY = ((height - camHeight) - camButtonHeight) / 2;
Graphics2D g1 = (Graphics2D) g;
Graphics2D g2 = (Graphics2D) g;
Graphics2D g3 = (Graphics2D) g;
RoundRectangle2D camButton = new RoundRectangle2D.Double(camButtonX, camButtonY, camButtonWidth, camButtonHeight, 25, 25);
RoundRectangle2D cameras = new RoundRectangle2D.Double(camX, camY, camWidth, camHeight, 25, 25);
// Background
g1.setColor(Color.BLACK);
g1.fillRect(0, 0, width, height);
addMouseListener(new MouseListener() {
#Override
public void mouseClicked(MouseEvent e) {
if (camButton.contains(e.getPoint())) {
camUp = !camUp;
repaint();
}
}
#Override
public void mousePressed(MouseEvent e) {
}
#Override
public void mouseReleased(MouseEvent e) {
}
#Override
public void mouseEntered(MouseEvent e) {
}
#Override
public void mouseExited(MouseEvent e) {
}
});
// Camera Button
g2.setColor(camColor);
g2.fill(camButton);
paintCameras = camUp;
// Cameras
g3.setColor(camColor);
if (paintCameras) {
g3.fill(cameras);
}
repaint();
}
Try to change make it when you click the camera button, a graphics object shows, but when clicked again, it closes.

To get this sort of program to work you should:
Create your MouseListener in code that is only called once, such as within a constructor
Create an instance field in the class to represent the camera button, such as a Rectangle or RoundRectangle2D and give it a viable object reference
In the mouse listener, toggle the state of a boolean variable if a click occurs within the shape that represents the camera button, e.g., camUp = !camUp; as you're doing
And then call repaint().
In the paintComponent method, check the state of the boolearn variable with an if statement, and if true, draw the image inside the if statement.
Keep the mouse listener and the painting code separate and in separate methods (or constructor).
Never call repaint() within a painting method as that will cause an uncontrolled animation. If you need a Swing animation, then use a Swing Timer so that you can fully control it. I don't see the need for it here.
For example:
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
#SuppressWarnings("serial")
public class GraphicsExample extends JPanel {
private static final int IMG_WIDTH = 400;
private static final int PREF_W = (3 * IMG_WIDTH) / 2;
private static final int PREF_H = PREF_W;
private static final Color BTN_COLOR = Color.RED;
private static final Color HOVER_COLOR = new Color(255, 100, 100);
private static final Color BTN_CLK_COLOR = new Color(180, 0, 0);
private static final int IMG_X = IMG_WIDTH / 2;
private static final int IMG_Y = IMG_X;
private double camX = 10;
private double camY = camX;
private double camWidth = 200;
private double camHeight = 80;
private Color buttonColor = Color.RED;
private RoundRectangle2D cameraButton = new RoundRectangle2D.Double(camX, camY, camWidth, camHeight, 25, 25);
private Image img;
private boolean showImage = false;
private JCheckBox toggleModeChkBox = new JCheckBox("Toggle Mode");
// private boolean toggleMode = true;
public GraphicsExample() {
add(toggleModeChkBox);
setPreferredSize(new Dimension(PREF_W, PREF_H));
img = createMyImage();
MouseAdapt mouseAdapt = new MouseAdapt();
addMouseListener(mouseAdapt);
addMouseMotionListener(mouseAdapt);
}
private Image createMyImage() {
BufferedImage img = new BufferedImage(IMG_WIDTH, IMG_WIDTH, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = img.createGraphics();
g2.setPaint(new GradientPaint(0, 0, Color.RED, 100, 100, Color.BLUE, true));
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
int gap = 10;
g2.fillOval(gap, gap, IMG_WIDTH - 2 * gap, IMG_WIDTH - 2 * gap);
g2.dispose();
return img;
}
private class MouseAdapt extends MouseAdapter {
#Override
public void mousePressed(MouseEvent e) {
if (cameraButton.contains(e.getPoint())) {
buttonColor = BTN_CLK_COLOR;
if (toggleModeChkBox.isSelected()) {
showImage = !showImage;
} else {
showImage = true;
}
} else {
buttonColor = BTN_COLOR;
}
repaint();
}
#Override
public void mouseReleased(MouseEvent e) {
if (cameraButton.contains(e.getPoint())) {
buttonColor = HOVER_COLOR;
} else {
buttonColor = Color.RED;
}
if (!toggleModeChkBox.isSelected()) {
showImage = false;
}
repaint();
}
#Override
public void mouseMoved(MouseEvent e) {
if (cameraButton.contains(e.getPoint())) {
buttonColor = HOVER_COLOR;
} else {
buttonColor = Color.RED;
}
if (!toggleModeChkBox.isSelected()) {
showImage = false;
}
repaint();
}
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setColor(buttonColor);
g2.fill(cameraButton);
if (showImage) {
int x = (getWidth() - IMG_WIDTH) / 2;
int y = (getHeight() - IMG_WIDTH) / 2;
g2.drawImage(img, x, y, this);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
GraphicsExample mainPanel = new GraphicsExample();
JFrame frame = new JFrame("GUI");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
});
}
}

How to add a JPanel on top of a canvas placing the mouse on the top of a Graphic element?

I am building the test application to improve later. I have a Java Graphic Element drawn on a canvas using a Game Loop (update,render). It is a red ball that changes its color when the mouse is placed on top of it.
I am trying to figure out a method to create a JPanel when the mouse is on top of the ball,to show some sort of "Hidden Information" inside the ball. My original idea is to display a histogram made with JFreeChart API as the "Hiden information, so I believe that if I create this JPanel I can later add the histogram to the JPanel created. Similar to this http://www.bitjuice.com.au/research/#hierarchicalclassificationexample. In the link, whenever you put the mouse on top of the rectangles, you display extra information.
So far I've got this code:
*Window.java * (The JFrame)
public class Window extends JFrame {
JLabel title_label = new JLabel();
public Window(int width, int height, String title, Animation animation){
setTitle(title);
setPreferredSize(new Dimension(width,height));
setMaximumSize(new Dimension(width,height));
setMinimumSize(new Dimension(width,height));
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setResizable(false);
setLocationRelativeTo(null);
add(animation);
add(title_label, BorderLayout.SOUTH);
setVisible(true);
animation.start();
}
public void update(){
title_label.setText(Animation.mouseX + " " + Animation.mouseY);
}
}
Animation.java(The game Loop)
public class Animation extends Canvas implements Runnable {
public static final int WIDTH = 1024, HEIGHT = WIDTH/12*9 ;
private Thread thread;
private boolean running = false;
public static int mouseX,mouseY;
public Window window;
Button button = new Button();
public Animation(){
window = new Window(WIDTH, HEIGHT,"Test", this);
addMouseMotionListener(new Handler(window));
addMouseListener(new Handler(window));
}
public void run() {
this.requestFocus();
long lastTime = System.nanoTime();
double amountOfTicks = 60.0;
double ns = 1000000000/amountOfTicks;
double delta = 0;
long timer = System.currentTimeMillis();
int frames = 0;
while(running){
long now = System.nanoTime();
delta += (now-lastTime) / ns;
lastTime = now;
while(delta >= 1){
update();
delta--;
}
if(running)
render();
frames++;
if(System.currentTimeMillis() - timer >1000){
//System.out.println(frames);
timer += 1000;
frames = 0;
}
}
stop();
}
public synchronized void start(){
thread = new Thread(this);
thread.start();
running = true;
}
public synchronized void stop(){
try{
thread.join();
running = false;
}catch(Exception e){
e.printStackTrace();
}
}
public static int getMouseX(){
return mouseX;
}
public static int getMouseY(){
return mouseY;
}
public static void setMouseX(int x){
mouseX = x;
}
public static void setMouseY(int y){
mouseY = y;
}
private void update(){
window.update();
button.update();
}
private void render(){
BufferStrategy bs = this.getBufferStrategy();
if(bs == null){
this.createBufferStrategy(4);
return;
}
RenderingHints rh = new RenderingHints(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
rh.put(RenderingHints.KEY_RENDERING,
RenderingHints.VALUE_RENDER_QUALITY);
Graphics g = bs.getDrawGraphics();
Graphics2D g2d = (Graphics2D)g;
g2d.setRenderingHints(rh);
g2d.setColor(Color.white);
g2d.fillRect(0, 0, WIDTH, HEIGHT);
button.render(g);
g.dispose();
g2d.dispose();
bs.show();
}
public static void main(String args[]){
new Animation();
}
}
Handler.java
public class Handler extends MouseAdapter {
int x,y;
private Window window;
public Handler(Window window){
this.window = window;
}
public void mouseMoved(MouseEvent e){
Animation.setMouseX(e.getX());
Animation.setMouseY(e.getY());
}
}
Button.java
public class Button {
Ellipse2D mask;
boolean mouseIsOn = false;
public Button(){
mask = new Ellipse2D.Double(500,350,50,50);
}
public void update(){
if(mask.contains(Animation.mouseX,Animation.mouseY)){
mouseIsOn = true;
}else
mouseIsOn = false;
}
public void render(Graphics g){
if(mouseIsOn)
g.setColor(Color.green);
else
g.setColor(Color.red);
g.fillOval(500,350, 50, 50);
}
}
I appreciate the help.

Heavy weight and light weight components don't mix. JPanel is a lightweight component and Canvas is heavyweight. Heavyweight components always get drawn on top of lightweight ones.
What you may want to do instead is just draw the mouseover portion directly to your canvas. You can use FontMetrics for drawing Strings if that is what you need.

Adding multiple MouseListeners dynamically JPanel

I am trying to add shapes onto a window using JPanel and then be able to click and drag them around the window. This works if I only have one shape; but when I add more shapes, the click and drag is very funky. It does drag but not with the mouse, it isn't proportional and doesn't drag with the mouse.
Any help is appreciated. Thanks!
public class SimpleDraw {
public static void main(String[] args) {
JFrame frame = new UMLWindow();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setBounds(30, 30, 1000, 700);
frame.getContentPane().setBackground(Color.white);
frame.setVisible(true);
frame.setLocationRelativeTo(null);
// Display the window.
frame.setVisible(true);
}
}
class UMLWindow extends JFrame {
Squares squares = new Squares();
private static final long serialVersionUID = 1L;
public UMLWindow() {
addMenus();
}
public void addMenus() {
getContentPane().add(squares);
JMenuBar menubar = new JMenuBar();
JMenu shapes = new JMenu("Shapes");
JMenuItem rectangleMenuItem = new JMenuItem("New Rectangle");
rectangleMenuItem.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
squares.addSquare(10, 10, 100, 100);
}
});
shapes.add(rectangleMenuItem);
menubar.add(shapes);
setJMenuBar(menubar);
setDefaultCloseOperation(EXIT_ON_CLOSE);
}
}
class Squares extends JPanel {
private static final long serialVersionUID = 1L;
private List<Path2D> squares = new ArrayList<Path2D>();
// private Path2D rect = new Path2D.Double();
int currentIndex;
public void addSquare(int x, int y, int width, int height) {
Path2D rect2 = new Path2D.Double();
rect2.append(new Rectangle(getWidth() / 2 - width / 2, getHeight() / 2
- height / 2, width, height), true);
squares.add(rect2);
// rect = rect2;
MyMouseAdapter myMouseAdapter = new MyMouseAdapter();
addMouseListener(myMouseAdapter);
addMouseMotionListener(myMouseAdapter);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
this.setOpaque(true);
this.setBackground(Color.WHITE);
Graphics2D g2 = (Graphics2D) g;
for (Path2D rect : squares) {
g2.draw(rect);
}
repaint();
}
class MyMouseAdapter extends MouseAdapter {
private boolean pressed = false;
private Point point;
#Override
public void mousePressed(MouseEvent e) {
if (e.getButton() != MouseEvent.BUTTON1) {
return;
}
for (int i = 0; i < squares.size(); i++) {
if (squares.get(i) != null
&& squares.get(i).contains(e.getPoint())) {
currentIndex = i;
pressed = true;
this.point = e.getPoint();
}
}
}
#Override
public void mouseDragged(MouseEvent e) {
if (pressed) {
int deltaX = e.getX() - point.x;
int deltaY = e.getY() - point.y;
squares.get(currentIndex).transform(
AffineTransform.getTranslateInstance(deltaX, deltaY));
point = e.getPoint();
repaint();
}
}
#Override
public void mouseReleased(MouseEvent e) {
pressed = false;
}
}
}

Lot of problems...
Most important, no you don't want to add a bunch of MouseListeners/MouseMotionListeners to your JPanel. You only want to add one, and have it control any and all squares that the JPanel holds.
Don't put a repaint() in your paintComponent method as that's a poor way to try to create an animation loop, a loop that you have absolutely no control over. Plus there's no need. The MouseAdapter should drive all the animation by itself.
class Squares extends JPanel {
private static final long serialVersionUID = 1L;
public Squares() {
MyMouseAdapter myMouseAdapter = new MyMouseAdapter();
addMouseListener(myMouseAdapter);
addMouseMotionListener(myMouseAdapter);
}
private List<Path2D> squares = new ArrayList<Path2D>();
// private Path2D rect = new Path2D.Double();
int currentIndex;
public void addSquare(int x, int y, int width, int height) {
Path2D rect2 = new Path2D.Double();
rect2.append(new Rectangle(getWidth() / 2 - width / 2, getHeight() / 2
- height / 2, width, height), true);
squares.add(rect2);
repaint(); // !!
// rect = rect2;
// !! MyMouseAdapter myMouseAdapter = new MyMouseAdapter();
// addMouseListener(myMouseAdapter);
// addMouseMotionListener(myMouseAdapter);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
this.setOpaque(true);
this.setBackground(Color.WHITE);
Graphics2D g2 = (Graphics2D) g;
for (Path2D rect : squares) {
g2.draw(rect);
}
// !! repaint();
}

Jpanel graphic not moving inside runnable

Any ideas why my oval is not moving to the right? I have a game loop but somehow the circle stays where it appears, instead of moving by 2pixels to the right every cycle.
The strange thing is that it enters the loop before actually painting. But then the graphics object show up(at a fixed position).
public class GamePanel extends JPanel implements Runnable {
public static int WIDTH = 1024;
public static int HEIGHT = WIDTH / 16 * 9;
private Thread t1;
boolean running;
private int FPS = 60;
private long optimalTime = 1000 / FPS;
private int heroX = 200;
private int heroY = 200;
public void addNotify(){
Dimension size = new Dimension(WIDTH,HEIGHT);
setPreferredSize(size);
setFocusable(true);
requestFocus();
running = true;
t1 = new Thread(this);
t1.start();
}
public void paintComponent (Graphics g){
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setColor(Color.WHITE);
g2.fillRect(0, 0, WIDTH, HEIGHT);
g2.setColor(Color.BLACK);
g2.fillOval(heroX, heroY, 50, 50);
g2.dispose();
}
public void run() {
long startTime;
long passedTime;
long waitTime;
while (running){
startTime = System.nanoTime();
System.out.println("Runs");
update();
draw();
repaint();
passedTime = System.nanoTime() - startTime;
waitTime = optimalTime - passedTime / 1000000;
try {
if (waitTime <= 0){
waitTime = 2;
}
Thread.sleep(waitTime);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
private void draw() {
}
private void update() {
heroX += 2;
}
}

You should use a swing Timer instead of trying to use threads. If you need to do something time consuming in the background, use SwingWorkers. It is possible to use your own threading with swing should you really need to (you need a twisted user case to need to do that), but do not try to do that until you have a good grasp of threads and the way to use them with swing.
public class GamePanel extends JPanel {
private static final int DELAY = 1000 / 60;
private final Timer timer;
// ...
private int heroX = 200;
private int heroY = 200;
public GamePanel() {
timer = new Timer(DELAY, new ActionListener() {
#Override
public void actionPerformed(final ActionEvent e) {
update();
repaint();
}
});
// ...
}
// No need to make this public
#Override
protected void paintComponent (Graphics g) {
// ...
}
#Override
public Dimension getPreferredSize() {
// Overriding is cleaner than using set*Size(). Search old questions to see why
}
public void startAnimation() {
timer.start();
}
public void stopAnimation() {
timer.stop();
}
// Remove addNotify() and run()
}

After reading and testing, I just wanted to do this. It works as intended, even if paintComponent is outside the EDT.
public class GamePanel extends JPanel implements Runnable {
public static int WIDTH = 1024;
public static int HEIGHT = WIDTH / 16 * 9;
private int cordX = WIDTH / 2;
private Thread t1;
private boolean running = true;
public void addNotify() {
super.addNotify();
Dimension size = new Dimension (WIDTH, HEIGHT);
setPreferredSize(size);
t1 = new Thread(this);
t1.start();
}
public void paintComponent(Graphics g) {
g.setColor(Color.WHITE);
g.fillRect(0, 0, WIDTH, HEIGHT);
g.setColor(Color.BLACK);
g.fillOval(cordX, HEIGHT /2 , 20, 20);
}
public void run() {
while(running) {
cordX += 2;
repaint();
try {
Thread.sleep(17);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}

Animating a Rectangle in Java

I've been trying to get this rectangle to move that I've created using a for loop. All that's happening with this code is that there is an original rectangle and then a new one next to that rectangle. No animation happens, only those two rectangles show on the window. What are some methods to get this rectangle to animate?
import java.awt.*;
import javax.swing.*;
public class Gunman extends JComponent {
/**
*
*/
private static final long serialVersionUID = 1L;
public int x = 10;
public int y = 10;
public int width = 8;
public int height = 10;
public void paint(Graphics g) {
g.setColor(Color.red);
g.drawRect (x, y, width, height);
g.fillRect (x, y, width, height);
for(int i = 0; i<=1024; i++){
g.setColor(Color.red);
g.drawRect(x++, y, width, height);
g.fillRect(x++, y, width, height);
}
}
}

Don't have program logic in a paint or paintComponent method, and by logic, I mean the for loop with "motion" as that just won't work. You want to
Almost never draw in a JComponent's paint method but rather in its paintComponent method.
Don't forget to call the super.paintComponent(g) method too, often as the first method call in the paintComponent(g) override.
Use a Swing Timer to step wise change the x and y values
call repaint() on the JComponent after the changes are made
For example
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Gunman extends JComponent {
private static final long serialVersionUID = 1L;
private static final int PREF_W = 900;
private static final int PREF_H = 700;
private static final int TIMER_DELAY = 30;
public int rectX = 10;
public int rectY = 10;
public int width = 8;
public int height = 10;
public Gunman() {
new Timer(TIMER_DELAY, new ActionListener() {
#Override
public void actionPerformed(ActionEvent actEvt) {
if (rectX < PREF_W && rectY < PREF_H) {
rectX++;
rectY++;
repaint();
} else {
((Timer)actEvt.getSource()).stop();
}
}
}).start();
}
#Override
public Dimension getPreferredSize() {
return new Dimension(PREF_W, PREF_H);
}
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.red);
g.drawRect(rectX, rectY, width, height);
g.fillRect(rectX, rectY, width, height);
}
public int getRectX() {
return rectX;
}
public void setRectX(int rectX) {
this.rectX = rectX;
}
public int getRectY() {
return rectY;
}
public void setRectY(int rectY) {
this.rectY = rectY;
}
private static void createAndShowGui() {
Gunman mainPanel = new Gunman();
JFrame frame = new JFrame("Gunman");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}

There are numerous ways to animate. Here is another example. Notice the location of repaint() inside a background thread. This paints directly on a JFrame. Use paintComponent() when painting on JPanels.
public static void main(String args[]) throws Exception {
new JFrame("Draw a red box") {
Point pointStart = new Point(50,50);
Point pointEnd = new Point(200,200);
public void paint(Graphics g) {
super.paint(g);
if (pointStart != null) {
g.setColor(Color.RED);
g.drawRect(pointStart.x, pointStart.y, pointEnd.x, pointEnd.y);
}}{
setDefaultCloseOperation(DISPOSE_ON_CLOSE);
setSize(300, 300);
setLocation(300, 300);
setVisible(true);
Thread t = new Thread(new Runnable() {
public void run() {
while (pointEnd.x > 0 && pointEnd.y > 0) {
pointEnd = new Point(--pointEnd.x, --pointEnd.y);
repaint();
try {
Thread.sleep(22);
} catch (InterruptedException e) {
e.printStackTrace();
}}
pointStart = null;
pointEnd = null;
}});
t.setDaemon(true);
t.start();
}};}

UPDATE: Ok previous answer was not so good from the old memory, here is the quickest, cheapest, most dirty way to get some animation quicksmart, you can copy and compile the code as is:
import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JComponent;
import javax.swing.JFrame;
public class Test extends JFrame {
public Gunman g = new Gunman();
public static void main( String[] args ) {
Test t = new Test();
t.setSize( 800, 600 );
t.setVisible( true );
t.getContentPane().add( t.g );
while ( true ) {
t.g.x = t.g.x + 1;
t.g.y = t.g.y + 1;
t.repaint();
try {
Thread.sleep( 100 );
} catch ( InterruptedException e ) {
}
}
}
public void paintComponent( Graphics g ) {
g.clearRect( 0, 0, 800, 600 );
}
}
class Gunman extends JComponent {
private static final long serialVersionUID = 1L;
public int x = 10;
public int y = 10;
public int width = 8;
public int height = 10;
public void paintComponent( Graphics g ) {
g.setColor( Color.red );
g.fillRect( x, y, width, height );
}
}
There are ALOT of shortcuts in this, as Hovercraft of Eels has said, this is not an 'ideal' way to do it, but it has the basic structure. You have a canvas (I have used the JFrame, again not really recommended), and you add a component to it. You must override paintComponent (if you are using swing, which I do recommend you do), and this will draw your component.
You then need to alter your component's position in some way (recommend a proper method call on the object that does this), and ask the canvas to repaint itself.
I have included the wait so you can see what's happening, but if you are thinking of game programming, you should look into creating a game loop to manage this, I recommend Killer game programming in java, you can get a free ebook version with a quick google search.