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MouseListener - MouseClicked

After 2 hours of searching I really can't find out why my code isn't working so I wonder if you could help.
All I want to see is "Clicked" when I press the button. My class MouseInput implements MouseListener and in the method mouseClicked all I got is system.out...("clicked");
import java.awt.Color;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
public class App implements Runnable {
private Display display;
private BufferStrategy bs;
private Graphics g;
private int cubeSide = 150;
private String title;
private int height,width;
private boolean running = false;
private Thread thread;
private MouseInput mouseInput;
public App(String title,int width,int height){
this.height=height;
this.width=width;
this.title=title;
display = new Display(title, width, height);
}
void setBufferStrategy(){
if(display.getCanvas().getBufferStrategy()==null){
display.getCanvas().createBufferStrategy(3);
}
bs = display.getCanvas().getBufferStrategy();
}
void init(){
setBufferStrategy();
mouseInput = new MouseInput();
display.getFrame().addMouseListener(mouseInput);
}
public synchronized void start(){
if(running==true)
return;
running=true;
thread = new Thread(this);
thread.start();
}
void render(){
}
#Override
public void run() {
init();
while(running){
render();
}
}
public synchronized void stop(){
}
}
MouseInput Code:
`import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
public class MouseInput implements MouseListener {
#Override
public void mouseClicked(MouseEvent arg0) {
// TODO Auto-generated method stub
System.out.println("Click");
}
#Override
public void mouseEntered(MouseEvent arg0) {
// TODO Auto-generated method stub
}
#Override
public void mouseExited(MouseEvent arg0) {
// TODO Auto-generated method stub
}
#Override
public void mousePressed(MouseEvent arg0) {
// TODO Auto-generated method stub
}
#Override
public void mouseReleased(MouseEvent arg0) {
// TODO Auto-generated method stub
}
}`
And for the Display class:
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import javax.swing.JFrame;
public class Display {
private JFrame frame;
private Canvas canvas;
private String title;
private int width,height;
public Display(String title,int width,int height){
this.width = width;
this.height=height;
this.title=title;
CreateDisplay();
}
public void CreateDisplay(){
frame = new JFrame(title);
canvas = new Canvas();
frame.setSize(width,height);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
frame.setFocusable(false);
frame.setResizable(false);
frame.setLocationRelativeTo(null);
canvas.setPreferredSize(new Dimension(width,height));
canvas.setMaximumSize(new Dimension(width,height));
canvas.setMinimumSize(new Dimension(width,height));
canvas.setBackground(Color.WHITE);
frame.add(canvas);
frame.pack();
}
public Canvas getCanvas(){
return canvas;
}
public JFrame getFrame(){
return frame;
}
}

I think the problem can be in display.getFrame().addMouseListener(mouseInput): I suppose display.getFrame() returns a an instance of a class extending java.awt.Component; according to API reference, addMouseListener
Adds the specified mouse listener to receive mouse events from this component.
I think an event on your button is not an event from the component you registered the listener on: can you try to register the listener on the canvas instance instead of on frame instance? May be the event originated from canvas, not from frame...

First, you can use an inline mouse adapter rather than extending mouse listener and needing a separate file for the mouse code.
Second, if you want to observe the click on your button, add the listener to your button.
yourJButton.addMouseListener( new MouseAdapter()
{
#Override
public void mouseClicked( MouseEvent e )
{
{
//do stuff
}
}
});

Painting in multiple classes

I am not very good with using multiple classes in java, as I've always found it easier to do all of my code in 1 class. Recently I've found the need to use a second class for a game I'm making and I'm running into an error.
Right now I'm just trying to spawn the enemy where and when the user clicks.
Main Class -
package joey.rts;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
public class RTSMain extends JFrame implements MouseListener{
/**
*
*/
private static final long serialVersionUID = -7122370886923000314L;
public static BufferedImage menu,enemy;
public static boolean onmenu,oneenemy;
public static void main(String[] args){
new RTSMain();
}
public RTSMain(){
init();
}
public void init(){
setSize(1700,1100);
setVisible(true);
setLocationRelativeTo(null);
setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setTitle("RTS");
addMouseListener(this);
}
public void paint(Graphics g){
Graphics2D g2 = (Graphics2D) g;
if(onmenu == true){
g2.drawImage(menu,0,0,this);
}
}
#Override
public void mouseClicked(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseEntered(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseExited(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mousePressed(MouseEvent e) {
Enemy enemy = new Enemy();
int x = e.getX();
int y = e.getY();
enemy.spawnEnemy(x, y);
}
#Override
public void mouseReleased(MouseEvent arg0) {
// TODO Auto-generated method stub
}
}
Enemy class -
package joey.rts;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;
public class Enemy{
/**
*
*/
public static BufferedImage enemy;
private static final long serialVersionUID = 7898827977636314494L;
public static RTSMain rts;
public static void main(String[] args){
try{
enemy = ImageIO.read(new File(javax.swing.filechooser.FileSystemView.getFileSystemView().getHomeDirectory() + "\\enemy.png"));
} catch (Exception e){
e.printStackTrace();
}
}
public static void spawnEnemy(int x, int y){
Graphics g = rts.getGraphics();
Graphics2D g2 = (Graphics2D) g;
g2.drawImage(enemy,x,y,null);
}
}

In your Main class update your mouseClicked function to be :
#Override
public void mouseClicked(MouseEvent e) {
Enemy enemy = new Enemy();
int x=e.getX(); // get mouse positionX
int y=e.getY();//get mouse positionY
enemy.spawnEnemy(x,y);//spawn Enemy
}
Consider saving the enemy objects if you need to reuse it later.
Also I see no need to extend anything in Enemy Class.
I've Updated Your Main and your Enemy class :
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.image.BufferedImage;
import javax.swing.JFrame;
public class Main extends JFrame implements MouseListener{
/**
*
*/
private static final long serialVersionUID = -7122370886923000314L;
public static BufferedImage menu,enemy;
public static boolean onmenu,oneenemy;
public static void main(String[] args){
new Main().setVisible(true);
}
public Main(){
init();
}
public void init(){
setSize(1700,1100);
setVisible(true);
setLocationRelativeTo(null);
setResizable(false);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setTitle("RTS");
addMouseListener(this);
}
#Override
public void paint(Graphics g){
Graphics2D g2 = (Graphics2D) g;
if(onmenu == true){
g2.drawImage(menu,0,0,this);
}
}
#Override
public void mouseClicked(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseEntered(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseExited(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mousePressed(MouseEvent e) {
Enemy enemy = new Enemy();
int x = e.getX();
int y = e.getY();
enemy.spawnEnemy(x, y,this.getGraphics());
}
#Override
public void mouseReleased(MouseEvent arg0) {
// TODO Auto-generated method stub
}
}
And this is the Enemy class :
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
public class Enemy{
public static BufferedImage enemy;
private static final long serialVersionUID = 7898827977636314494L;
public Enemy(){
try {
//MAKE SURE THAT THIS IS THE CORRECT IMAGE PATH
enemy = ImageIO.read(new File(javax.swing.filechooser.FileSystemView.getFileSystemView().getHomeDirectory() + "\\enemy.png"));
} catch (IOException ex) {
Logger.getLogger(Enemy.class.getName()).log(Level.SEVERE, null, ex);
}
}
public void spawnEnemy(int x, int y,Graphics g){
Graphics2D g2 = (Graphics2D) g;
g2.drawImage(enemy,x,y,null);
}
}
I've removed the instance variable of Main that was on Enemy class.
I've removed the static modifier for the spawnEnemy function.
I've sent the graphics object as an attribute to spawnEnemy function .
I've Moved the code that was in main method in Enemy class to the Enemy Constructor.
Hope it helps !

It just seemed easier to paste an answer than to try to explain it in a comment. Your OO is a bit off. Add this to your RTSMain class:
protected ArrayList<Enemy> enemies = new ArrayList<Enemy>();
protected BufferedImage enemyImage = null;
...
public void init() {
...
// everything you already have...
enemyImage = //read in your enemy image here
...
}
...
#Override
public void mouseClicked(MouseEvent e) {
// this takes place of Enemy.spawn(), get rid of it
int x = e.getX(); // get mouse positionX
int y = e.getY(); //get mouse positionY
Enemy enemy = new Enemy( enemyImage, x, y );
Enemies.add( enemy );
// Iterate over list above to draw each enemy in your paintComponent method
}
Also, JFrame doesn't have a paintComponent() method, which you need to override to do your painting (paint() is deprecated). Add a JPanel, override it's paintComponent() and so on. For a game, you'll probably want to create a game loop to do your painting, unless it's very turn-based.
Happy coding.

Why won't circle draw where I click

So I'm trying to draw a circle where a user clicks, which can then be re-sized by the bar down below. Everything works except for that the circle won't draw where I want it to. Any suggestions?
Here is my Panel
import java.awt.*;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.*;
import javax.swing.event.*;
public class TestClass extends JFrame {
private JSlider slide;
private MainClass myPanel;
public int x1=0;
public int y1=0;
public TestClass(){
super("The Title");
myPanel = new MainClass();
myPanel.setBackground(Color.YELLOW);
slide = new JSlider(SwingConstants.HORIZONTAL, 0, 200, 10);
slide.setMajorTickSpacing(10);
slide.setPaintTicks(true);
slide.addChangeListener(
new ChangeListener(){
public void stateChanged(ChangeEvent e){
myPanel.checkDiameter(slide.getValue());
}
}
);
HandlerClass handler = new HandlerClass();
slide.addMouseListener(handler);
add(slide, BorderLayout.SOUTH);
add(myPanel, BorderLayout.CENTER);
}
public int setX1(){
return x1;
}
public int setY1(){
return y1;
}
private class HandlerClass implements MouseListener{
#Override
public void mouseClicked(MouseEvent event) {
// TODO Auto-generated method stub
x1=event.getX();
y1=event.getY();
repaint();
}
#Override
public void mousePressed(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseReleased(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseEntered(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseExited(MouseEvent e) {
// TODO Auto-generated method stub
}
}
}
Here is the other important class which creates a window and call TestClass;
import java.awt.*;
import javax.swing.*;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
public class MainClass extends JPanel{
private int d = 10;
public void paintComponent(Graphics g){
super.paintComponent(g);
TestClass values = new TestClass();
g.setColor(Color.CYAN);
g.fillOval(values.setX1()+50, values.setY1(), d, d);
}
public void checkDiameter(int newD)
{
//New format for if statements
d = (newD >= 0 ? newD //if
: 10//else
);
repaint();
}
public Dimension getPreferredSize(){
return new Dimension(200,200);
}
public Dimension getMinimumSize(){
return getPreferredSize();
}
}

Hey Guys I found a way to get it working.
import java.awt.*;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.*;
import javax.swing.event.*;
public class TestClass extends JFrame {
private JSlider slide;
private MainClass myPanel;
public static int x1=0,y1=0;
public TestClass(){
super("The Title");
myPanel = new Panel();
myPanel.setBackground(Color.YELLOW);
//Allows you to re-size the drawn circle
slide = new JSlider(SwingConstants.HORIZONTAL, 0, 200, 10);
slide.setMajorTickSpacing(10);
slide.setPaintTicks(true);
slide.addChangeListener(
new ChangeListener(){
public void stateChanged(ChangeEvent e){
myPanel.checkDiameter(slide.getValue());
}
}
);
//Create a way to handle user mouse events
HandlerClass handler = new HandlerClass();
myPanel.addMouseListener(handler);
add(slide, BorderLayout.SOUTH);
add(myPanel, BorderLayout.CENTER);
}
private class HandlerClass implements MouseListener{
#Override
public void mouseClicked(MouseEvent event) {
// TODO Auto-generated method stub
Right here is what is new with the code, this method gets the x and y coordinates of a click and sends it to MainClass object myPanel which has the setPosition method; class show before.
myPanel.setPosition(event.getX(),event.getY());
repaint(); }
#Override
public void mousePressed(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseReleased(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseEntered(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseExited(MouseEvent e) {
// TODO Auto-generated method stub
}
}
}
Here is the MainClass class, it is poorley named as it's not actually the main class...
import java.awt.;
import javax.swing.;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
public class Panel extends JPanel{
private int x1,y1;
private int d = 10;
public void paintComponent(Graphics g){
super.paintComponent(g);
g.setColor(Color.CYAN);
g.fillOval(x1, y1, d, d);
}
public void checkDiameter(int newD)
{
//New format for if statements
d = (newD >= 0 ? newD //if
: 10//else
);
repaint();
}
public void setPosition(int newX, int newY) {
this.x1 = newX;
this.y1 = newY;
repaint();
}
public Dimension getPreferredSize(){
return new Dimension(200,200);
}
public Dimension getMinimumSize(){
return getPreferredSize();
}
}

How to rearrange layed out JPanels in a JPanel via drag

I have a very simple example. I'm trying to get working before i try and apply this to the more complex program I have planned. But I'm trying to be able to drag and drop the JPanels that are in say a Flow or Vertical Layout.
I'm not really sure where to start, as this isn't really anything I've dealt with before. But from what I've researched, it would seem that I surely need a listener on each JPanel, that listens for clicks. From here it will gather initial data from a mousePressed, and run a overridden repaint(), that will update the coordinates of the panel in the container. Then according to where the coordinate is placed, it will repack() and hopefully resize the panels.
Am I onto the right track?
import java.awt.FlowLayout;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.border.Border;
public class DraggablePanels extends JFrame {
/**
*
*/
private static final long serialVersionUID = 1L;
Border raisedbevel = BorderFactory.createRaisedBevelBorder();
int px, py;
JPanel main = new JPanel();
public DraggablePanels(){
this.setLayout(new FlowLayout());
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
this.setResizable(false);
JPanel p1 = new JPanel();
p1.addMouseListener(new MouseListener(){
#Override
public void mousePressed(MouseEvent e) {
// TODO Auto-generated method stub
px = e.getX();
py = e.getY();
}
#Override
public void mouseReleased(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseEntered(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseClicked(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseExited(MouseEvent e) {
// TODO Auto-generated method stub
}
});
p1.setBorder(raisedbevel);
JPanel p2 = new JPanel();
p2.addMouseListener(new MouseListener(){
#Override
public void mousePressed(MouseEvent e) {
// TODO Auto-generated method stub
px = e.getX();
py = e.getY();
}
#Override
public void mouseReleased(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseEntered(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseClicked(MouseEvent e) {
// TODO Auto-generated method stub
}
#Override
public void mouseExited(MouseEvent e) {
// TODO Auto-generated method stub
}
});
p2.setBorder(raisedbevel);
p1.add(new JLabel("Thing 1"));
p2.add(new JLabel("Thing 2"));
main.add(p1);
main.add(p2);
add(main);
pack();
setVisible(true);
}
public static void main (String args[]){
DraggablePanels d = new DraggablePanels();
}
}

Check this Sample Application for rearranging jpanel:
http://www.bryanesmith.com/docs/drag-and-drop-java-5/

SWING - drawing straight lines, which won't appear when compiled

I am trying to draw lines with the mouse in a JFrame window, and when I try to do so, it doesn't work! Please ignore the menu, I am trying to do things with that later! What did I miss! I would be grateful if you could give me some hints!
public class newGUI extends JFrame implements ActionListener, MouseMotionListener, MouseListener {
private static final long serialVersionUID = 1L;
public static final int WIDTH = 300;
public static final int HEIGHT = 200;
Point point1;
Point point2;
Line2D line2d;
public static void main(String[] args){
newGUI gui = new newGUI();
gui.setVisible(true);
}
public newGUI()
{
super("Menu Demonstration");
setSize(WIDTH, HEIGHT);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JMenu colorMenu = new JMenu("Choose Colors");
JMenuItem greenChoice = new JMenuItem("GREEN");
greenChoice.addActionListener(this);
colorMenu.add(greenChoice);
JMenuItem redChoice = new JMenuItem("RED");
colorMenu.add(redChoice);
JMenuBar bar = new JMenuBar();
bar.add(colorMenu);
setJMenuBar(bar);
addMouseListener(this);
addMouseMotionListener(this);
}
#Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
}
#Override
public void mouseClicked(MouseEvent arg0) {
// TODO Auto-generated method stub
}
#Override
public void mouseEntered(MouseEvent arg0) {
// TODO Auto-generated method stub
}
#Override
public void mouseExited(MouseEvent arg0) {
// TODO Auto-generated method stub
}
#Override
public void mousePressed(MouseEvent arg0) {
// TODO Auto-generated method stub
point1=arg0.getPoint();
}
#Override
public void mouseReleased(MouseEvent arg0) {
// TODO Auto-generated method stub
}
#Override
public void mouseDragged(MouseEvent arg0) {
// TODO Auto-generated method stub
point2=arg0.getPoint();
line2d=new Line2D.Double(point1, point2);
repaint();
}
#Override
public void mouseMoved(MouseEvent arg0) {
// TODO Auto-generated method stub
}
public void paintComponent(Graphics g){
Graphics2D g2d = (Graphics2D) g;
if(point1!=null && point2!=null){
g2d.setPaint(Color.RED);
g2d.setStroke(new BasicStroke(1.5f));
g2d.draw(line2d);
repaint();
}
}
}

Always start class names with a capital letter i.e NewGui
Use Event Dispatch Thread for creating and changing of UI components
Do not extend JFrame class uncecessarily
Do not call setSize(..) rather call JFrame#pack() on JFrame instance
JFrame does not have a paintComponent(..), rather add custom JPanel and override its paintComponent(..) and getPreferredSize(..)
Dont forget to call super.paintComponent(..) in your custom JPanel
Do not call repaint() from within paintComponent(..) (this will cause an infinite loop of repainting more than needed)
Also where possible (if it is not used by other classes) use anonymous MouseListeners/MouseMotionListeners and rather use MouseAdapter instead of MouseListener/MouseMotionListeners etc.
Here is an example I made (basically your code with fixes mentioned):
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Line2D;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class NewGui implements ActionListener {
private static final long serialVersionUID = 1L;
public static final int WIDTH = 300;
public static final int HEIGHT = 200;
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
NewGui gui = new NewGui();
}
});
}
public NewGui() {
initComponents();
}
#Override
public void actionPerformed(ActionEvent arg0) {
// TODO Auto-generated method stub
}
private void initComponents() {
JFrame frame = new JFrame("Menu Demonstration");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JMenu colorMenu = new JMenu("Choose Colors");
JMenuItem greenChoice = new JMenuItem("GREEN");
greenChoice.addActionListener(this);
colorMenu.add(greenChoice);
JMenuItem redChoice = new JMenuItem("RED");
colorMenu.add(redChoice);
JMenuBar bar = new JMenuBar();
bar.add(colorMenu);
frame.setJMenuBar(bar);
frame.add(new MyPanel());
frame.pack();
frame.setVisible(true);
}
}
class MyPanel extends JPanel {
Point point1;
Point point2;
Line2D line2d;
public MyPanel() {
addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent me) {
super.mousePressed(me);
point1 = me.getPoint();
}
});
addMouseMotionListener(new MouseAdapter() {
#Override
public void mouseDragged(MouseEvent me) {
super.mouseDragged(me);
// TODO Auto-generated method stub
point2 = me.getPoint();
line2d = new Line2D.Double(point1, point2);
repaint();
}
});
}
//so our panel will be visible
#Override
public Dimension getPreferredSize() {
return new Dimension(400, 200);
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
//Set anti-alias!
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
if (point1 != null && point2 != null) {
g2d.setPaint(Color.RED);
g2d.setStroke(new BasicStroke(1.5f));
g2d.draw(line2d);
}
}
}