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Icon Object is flying diagonally out of frame

After writing and modifying this code, I encountered with this problem:
Clicking with the mouse is making the object appear for a secong and then fly out diagonally of the image bounds.
apparentally the function "repaint()" is responsible for this occurence in "paint(Graphics g)" block.
eliminating the reapaint() part make the object appear for a second and then dissappear.
public class MainWindow extends JFrame implements MouseListener
{
public BufferedImage myImage,packman_icon;
private ArrayList<Point> points;
public MainWindow()
{
initGUI();
this.addMouseListener(this);
}
private void initGUI()
{
MenuBar menuBar = new MenuBar();
Menu File = new Menu("File");
Menu Run=new Menu("Run");
Menu Insert=new Menu("Insert");
MenuItem New=new MenuItem("New");
MenuItem Open = new MenuItem("Open");
MenuItem Save=new MenuItem("Save");
MenuItem start=new MenuItem("start");
MenuItem stop=new MenuItem("stop");
MenuItem packman=new MenuItem("packman");
MenuItem fruit=new MenuItem("fruit");
menuBar.add(File);
menuBar.add(Run);
menuBar.add(Insert);
File.add(New);
File.add(Open);
File.add(Save);
Run.add(start);
Run.add(stop);
Insert.add(packman);
Insert.add(fruit);
this.setMenuBar(menuBar);
try {
myImage = ImageIO.read(new File("C:\\Users\\Owner\\Desktop\\Matala3\\Ariel1.png"));//change according to your path
packman_icon=ImageIO.read(new File("C:\\Users\\Owner\\Desktop\\pacman_icon.gif"));
} catch (IOException e) {
e.printStackTrace();
}
}
int x = -1;
int y = -1;
public void paint(Graphics g)
{
super.paintComponents(g);
g.drawImage(myImage, 0, 0, this);
g.drawImage(packman_icon, x, y, 20, 20, this);
if(x!=-1 && y!=-1)
{
int r = 10;
x = x - (r / 2);
y = y - (r / 2);
g.fillOval(x, y, r, r);
}
}
#Override
public void mouseClicked(MouseEvent arg) {
System.out.println("mouse Clicked");
System.out.println("("+ arg.getX() + "," + arg.getY() +")");
x = arg.getX();
y = arg.getY();
repaint();
}
}
public class Main
{
public static void main(String[] args)
{
MainWindow window = new MainWindow();
window.setVisible(true);
window.setSize(window.myImage.getWidth(),window.myImage.getHeight());
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
I want the image icon to stay in picture and not dissappear, thus creating multiple objects that appear on the picture.
**I edited the code acoording to instructions: deleted reapint()
method from paint and used
super.paintComponet(g)
but now it inly appears for a brief second and then dissappears.

Don't use AWT components in a Swing application. Swing component start with "J" (JMenuBar, JMenu, JMenuItem).
//public void paint(Graphics g)
protected void paintComponent(Graphics g)
The original comment was to override paintCompnent(...).
Also, painting is a dynamic process and the painting methods are invoked whenever Swing determines the components needs to be painted so you need to make sure to reset the state each time the component is painted.
Therefore, a painting method should NOT change the state of the class. You are using the x/y variables for two purposes:
to paint the image
to paint the oval.
Because you update the x/y variable in the painting method, this will affect the location of the image the next time the painting method is invoked.
If you want the image fixed then you need to use separate variables for the location of the image.
You will also need to reset the x/y variables in the painting method to paint the ovals, since these variables are local and need to be reset each time the painting is done.

How to create new instances of a timer Task instead of canceling and restarting it all over?

Well the thing is that I have a project where I have to make a game on java. In my game there's a spaceship that shoots lasers. I have the mechanics for shooting the laser more or less figured out but I am currently using a timer task to make the laser fly through the JFrame and give the impression a laser was shot.
Problem is that TimerTask seems to bug out as soon as I start shooting many times.
The main goal is to move an object across the screen at a given speed.
Is there something else I could do to achieve this? Is there a better way to implement this?
I appreciate all the help I could get, Thanks.
Here is some of the code:
public Space() {
this.setBackground(Color.BLACK);
this.setCursor(Cursor.getDefaultCursor());
this.addMouseMotionListener(new MouseAdapter() {
public void mouseMoved(MouseEvent e) {
repaint();
x = e.getX()-spaceFighterIcon.getIconHeight()/2;
y = e.getY()-spaceFighterIcon.getIconWidth()/2;
}
public void mouseDragged(MouseEvent e) {
repaint();
x = e.getX()-spaceFighterIcon.getIconHeight()/2; //Positions the cursor on the middle of the spaceShip and viceVersa
y = e.getY()-spaceFighterIcon.getIconWidth()/2;
}
}
);
this.addMouseListener(new MouseAdapter(){
public void mousePressed(MouseEvent e) {
if(timerRunning = true){
laserTimer.cancel();
laserTimer.purge();
laserFired = false;
}
if(SwingUtilities.isLeftMouseButton(e)){ // Gets where the laser is going to be shot from
repaint();
laserX = e.getX()-spaceFighterIcon.getIconWidth()/6;
laserY = e.getY();
laserFired = true;
}
if(SwingUtilities.isRightMouseButton(e)){
}
if(SwingUtilities.isMiddleMouseButton(e)){
}
}
});
}
public void paintComponent(Graphics g) {
this.graphics = g;
super.paintComponent(g);
spaceFighterIcon.paintIcon(this, g, x, y);
if(laserFired == true){
shootLaser();
}
}
public void shootLaser(){
laserIcon.paintIcon(this, graphics, laserX, laserY-50); // paints the laser
laserTimer = new Timer();
laserTimer.schedule(new AnimateLasers(), 0, 200); // Timer to move the laser across the frame
timerRunning = true;
repaint();
}
public void lasers(){
laserY = laserY-1; // function to move the laser
if(laserY <= 0){
laserTimer.cancel();
laserTimer.purge();
}
}
public class AnimateLasers extends TimerTask {
public void run() {
lasers();
repaint();
}
}

Start by taking a look at Concurrency in Swing and How to use Swing Timers instead of java.util.Timer.
Swing Timer is safer to use with Swing, as it executes it ticks within the context of the Event Dispatching Thread
Also take a look at Painting in AWT and Swing and Performing Custom Painting for more details about how painting works
Don't maintain a reference to the Graphics context outside of the paint method. Your component will be told when it should repaint it self by the system (via the call to the paintComponent method), essentially, you use the time to update the location of the "laser" and call repaint, then paint the laser within the paintComponent when it's called by the paint system

Drawing a rectangle on screen as an "area selection" tool (Java)

I want the user of my program to be able to highlight an area on a JFrame to select a group of items on screen. The code I posted below works, but it is very choppy, which becomes quite an eyesore every single time the JFrame repaints. Here's an image of what I'm talking about: http://i1065.photobucket.com/albums/u400/mfgravesjr/choppy%20draw%20rectangle_zpsspqsqnyf.png
Maybe someone here has suggestions to improve my code?
This is the mouseDragged method in MouseMotionListener:
public void mouseDragged(MouseEvent me)
{
if(groupingTerr&&me.getSource()==background)
{
endPoint = MouseInfo.getPointerInfo().getLocation();
topLeftRect = new Point(Math.min(startPoint.x,endPoint.x),Math.min(startPoint.y,endPoint.y));
bottomRightRect = new Point(Math.max(startPoint.x,endPoint.x),Math.max(startPoint.y,endPoint.y));
for(Point p:map.territoryPoints)
{
if(p.x>topLeftRect.x&&p.x<bottomRightRect.x&&p.y>topLeftRect.y&&p.y<bottomRightRect.y)img.getGraphics().drawImage(selectedIco,p.x-selectedIco.getWidth()/2,p.y-selectedIco.getHeight()/2,null);
else img.getGraphics().drawImage(defaultIco,p.x-defaultIco.getWidth()/2,p.y-defaultIco.getHeight()/2,null);
}
background.repaint();
}
}
This is the private overridden JFrame class
private static class DrawableJFrame extends JFrame
{
#Override
public void paint(Graphics g)
{
super.paint(g);
g.setColor(new Color(0,0,0,100));
g.drawRect(topLeftRect.x,topLeftRect.y,bottomRightRect.x-topLeftRect.x,bottomRightRect.y-topLeftRect.y);
g.setColor(new Color(200,10,10,100));
g.fillRect(topLeftRect.x,topLeftRect.y,bottomRightRect.x-topLeftRect.x,bottomRightRect.y-topLeftRect.y);
}
}
The image is original artwork. Please do not use it.

How to change the color of an individual ellipse when clicking a jButton?

I want to be able to click the JButton and change the next individual ellipse I make to its respective color, Red or Black, from its default Blue. So far I'm able to change the color of all the ellipses I have made.
public class MainClient {
private JFrame frame;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
MainClient window = new MainClient();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*/
public MainClient() {
initialize();
}
/**
* Initialize the contents of the frame.
*/
private void initialize() {
frame = new JFrame();
frame.setBounds(100, 100, 800, 600);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final SpriteField panel = new SpriteField();
panel.setBounds(0, 110, 782, 331);
panel.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
int tX = e.getX();
int tY = e.getY();
panel.CreateObjectAt(tX,tY);
}
});
frame.getContentPane().setLayout(null);
panel.setBackground(Color.LIGHT_GRAY);
frame.getContentPane().add(panel);
final JButton btnRed = new JButton("black");
btnRed.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
panel.setColor(Color.BLACK);
}
});
btnRed.setBounds(229, 500, 97, 25);
frame.getContentPane().add(btnRed);
JButton btnRed_1 = new JButton("red");
btnRed_1.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
panel.setColor(Color.RED);
}
});
btnRed_1.setBounds(342, 500, 97, 25);
frame.getContentPane().add(btnRed_1);
}
}
I have a SriteField Class
public class SpriteField extends JPanel
{
ArrayList<RoundSprite>mSprites = new ArrayList<RoundSprite>();
private Color color = Color.BLUE;
#Override
protected void paintComponent(Graphics g)
{
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;
AffineTransform tOldTransform = g2.getTransform();
for(RoundSprite tOne:mSprites)
{
tOne.DrawSprite(g2, color);
}
g2.setTransform(tOldTransform);
}
public void CreateObjectAt(int tX, int tY)
{
//make sprite
RoundSprite mLonely = new RoundSprite();
//set position
mLonely.SetPosition(tX, tY);
//add to array
mSprites.add(mLonely);
repaint();
}
public void setColor(Color color)
{
this.color = color;
repaint();
}
}
I have a RoundSprite Class
public class RoundSprite
{
int mX;
int mY;
private Color color;
void DrawSprite(Graphics2D g2, Color color)
{
AffineTransform tOldTransform = g2.getTransform();
g2.setColor(color);
g2.translate(mX, mY); //got it out from the corner
g2.draw(new Ellipse2D.Double(-15, -22, 30, 50));
g2.setTransform(tOldTransform);
}
public void SetPosition(int tX, int tY) //g2.translate
{
mX = tX;
mY = tY;
}

There are three core issues...
One
In order for the panel_1 MouseListener to change the color of the sprites within panel, the MouseListener requires a reference to the panel.
You could declare the panel as final within the initialize method, but I prefer to make the panel a private instance field of the MainClient.
Two
In order to change the color, the SpriteField needs to provide a means by which interested parties can request a change.
This is going to require SpriteField to provide some kind of method that interested parties can call when they need to, for example, a setColor method...
public class SpriteField extends JPanel {
private Color color = Color.BLACK;
//...
public void setColor(Color color) {
this.color = color;
repaint();
}
Then panel_1's MouseListener can now reference the SpriteField and call a method which can produce a change...
panel_1.addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
System.out.println("Click");
panel.setColor(Color.BLUE);
}
});
Three
You need some way to tell the sprite what color it should be...
This one depends on what it is you want to achieve...
If you want to paint ALL the sprites the same color, then you need some way to tell the sprites which color they should use, for example, you could change the DrawSprite method to accept a Color parameter...
public class RoundSprite {
//...
void DrawSprite(Graphics2D g2, Color color) {
And within the SpriteField paintComponent, pass the color to the sprite
public class SpriteField extends JPanel {
//...
private Color color = Color.BLACK;
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
AffineTransform tOldTransform = g2.getTransform();
for (RoundSprite tOne : mSprites) {
tOne.DrawSprite(g2, color);
}
g2.setTransform(tOldTransform);
}
Now, this will paint ALL the sprites within the field the same color, if you want to change the color of individual sprites, this comes infinitely more complicated...
Lets leave aside the issues of selecting a sprite for the moment...
Basically, you would need to apply the same principle from point Two to the RoundSprite class.
You would need to supply a method that could set/get the desired color. You would need to store this value in an instance field of the RoundSprite class and when DrawSprite is called, apply that Color to the Graphics context.
This would mean that SpriteField won't need to perform any color management, beyond passing the request for change from a caller to the selected sprite, so it would still need a setColor method...
Side Notes...
You might like to have a read through Code Conventions for the Java TM Programming Language, it will make it easier for people to read your code and for you to read others
Avoid using null layouts, pixel perfect layouts are an illusion within modern ui design. There are too many factors which affect the individual size of components, none of which you can control. Swing was designed to work with layout managers at the core, discarding these will lead to no end of issues and problems that you will spend more and more time trying to rectify
Oh, and you realise that there already is a JButton class that probably should be used instead of a JPanel with a MouseListener....?

Drawing problem in java

I am a new in java, and I need to implement a paint application, and I'm kinda stuck at the beggining, I managed to draw lines to a JPanel which I added to a JFrame, but each line drawn resets the entire drawing, and in the draw area remains only the last line drawn. I hope I made myself understood, here his the code:
class Shapes extends JFrame {
public JFrame mf = new JFrame("Paint");
DrawArea da = new DrawArea();
JToggleButton lineButton = new JToggleButton(new ImageIcon("line.gif"));
JToggleButton brushButton = new JToggleButton();
JToggleButton pencilButton = new JToggleButton();
JToggleButton eraserButton = new JToggleButton(new ImageIcon("eraser_icon.png"));
JToggleButton rectangleButton = new JToggleButton();
JToggleButton ovalButton = new JToggleButton();
Shapes() {
da.setBounds(120, 50, 500, 350);
da.setBackground(Color.YELLOW);
mf.setSize(700, 500);
mf.setLayout(null);
lineButton.setBounds(0, 50, 40, 40);
brushButton.setBounds(40, 50, 40, 40);
eraserButton.setBounds(0, 90, 40, 40);
pencilButton.setBounds(40, 90, 40, 40);
rectangleButton.setBounds(0, 130, 40, 40);
ovalButton.setBounds(40, 130, 40, 40);
mf.setBackground(Color.red);
mf.add(lineButton);
mf.add(brushButton);
mf.add(pencilButton);
mf.add(eraserButton);
mf.add(rectangleButton);
mf.add(ovalButton);
mf.add(da);
mf.show();
mf.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
mf.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
System.out.println("x:" + e.getX() + "y:" + e.getY() + "\n" + "x2:" + e.getXOnScreen() + "y2:" + e.getYOnScreen());
}
});
eraserButton.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent e)
{
eraserButton.setSelectedIcon(new ImageIcon("eraser_icon_selected.png"));
}
});
lineButton.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent e)
{
lineButton.setSelectedIcon(new ImageIcon("line_selected.png"));
}
});
da.addMouseListener(new MouseAdapter() {
public void mousePressed(MouseEvent e) {
da.setXvalue(e.getX());
da.setYvalue(e.getY());
}
public void mouseReleased(MouseEvent e) {
da.setX2value(e.getX());
da.setY2value(e.getY());
da.repaint();
}
});
da.addMouseMotionListener(new MouseAdapter() {
public void mouseDragged(MouseEvent e) {
da.repaint();
da.setX2value(e.getX());
da.setY2value(e.getY());
}
});
}
}
public class DrawArea extends JPanel {
int x1value,y1value,x2value,y2value;
public int getX2value() {
return x2value;
}
public void setX2value(int x2value) {
this.x2value = x2value;
}
public int getY2value() {
return y2value;
}
public void setY2value(int y2value) {
this.y2value = y2value;
}
public JPanel dra=new JPanel();
public int getXvalue() {
return x1value;
}
public void setXvalue(int xvalue) {
this.x1value = xvalue;
}
public int getYvalue() {
return y1value;
}
public void setYvalue(int yvalue) {
this.y1value = yvalue;
}
public void paint(Graphics g)
{
super.paint(g);
g.setColor(Color.red);
g.drawLine(getXvalue(),getYvalue(),getX2value(),getY2value());
}
}
class Paint extends JPanel
{
public static void main(String args[])
{
Shapes s=new Shapes();
}
}

See Custom Painting Approaches for two solutions. The examples draw rectangles, but the concept is the same for lines.

Override paintComponent(), not paint(). Read this tutorial. When a panel needs to be redrawn, you call that panels repaint() method.

Paint is called by the window manager any time it considers that area 'unfresh'. If you do it the way you're doing it right now, you will draw the last line drawn every time.
The proper way to do this would be to make a BufferedImage in memory and draw on that. Then, in the paint method, blit the BufferedImage onto the surface. This also makes scrolling and zooming quite easy to do.
Whenever you perform such an action, invalidate the surface so that the window manager will call the paint method for you.

You are only storing one line, and overwriting it each time, so when the component is repainted, the old one is erased and the new one is redrawn.
The expectation of paintComponent and the like is that your implementation will draw EVERY graphical element that you want to appear, each time it is called.
Instead of storing x1, y1, x2, y2, you should make a LineSegment class or similar that stores those values. Then, when you paint, you call g.drawLine() for each LineSegment object that you've stored (presumably in an ArrayList or similar). Then, when the component is redrawn, all of your line segments should appear on the screen.

A little bit off topic, but I had a few uncomfortable minutes cause I used update() instead of repaint(). I advice to everyone working with SWING to spend some time checking which methods should handled as thread safe and which ones has to be on EDT (Event Dispatcher Thread) to make sure you won't get some unexpected errors.
This is a good article about this.
Also, at the beginning think through if you want to have an undo/redo system in your app...
If so, than how many steps you want to allow being withdrawn. If you want to allow this feature than you cannot just draw and forget about what you draw last time.
Also it would be not memory efficient to store all the images you draw so far. I'm not an expert and I'm not saying this is the best practice but I would go this way:
I would make two lists.
One of them would store the applied drawing actions,
the other would contain the withdrawn drawing actions.
Drawing action would be an interface and some class would implement it for each specific kind of drawing action (LineDrawAction, CirceDrawAction...).
When you draw a new line or whatever you would empty the withdrawn actions list and add it to the applied action list. When someone undo the last action, than I would just remove the last drawing actions from the applied list and would add to the withdrawn list (etc...). Depending on if you want to allow only the last x action to be undone when a list reaches this x limit I would remove the first drawing action from the list or queue and would finally draw to the picture - this means permanent drawing and this cannot be undone.
I hope it's clear and useful even if not a direct answer to your question.