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Mouse input problems in java

Edit:
I have an application that uses a swing Timer to control when an action listener interface fires. The mouse logic works but occasionally will not detect a click. Below is my commented code.
public class Board extends JPanel implements MouseListener, MouseMotionListener, ActionListener
{
private MainMenu mainMenu = new MainMenu();
private static String State; /*Makes the control flow simpler, just checking
strings that describe the state. All the states are contained in GameState class.*/
public Board()
{
this.addMouseListener(this);
this.addMouseMotionListener(this);
setVisible(true);
mainMenu.initLogIn(); /*This just loads the button images*/
Timer timer = new Timer(12, this); /*(millisecond delay, tells this class
to update any actionlistener (mouselistener etc)*/
timer.start();
}
public void paint(Graphics G)
{
super.paint(G);
Graphics G2d = (Graphics2D)G;
/*Main menu paint logic*/
// This paints buttons from mainMenu class on screen
G.drawImage(mainMenu.getTopic1().getspriteImage(),
mainMenu.getTopic1().getxCoord(),
mainMenu.getTopic1().getyCoord(),this);
G.drawImage(mainMenu.getTopic2().getspriteImage(),
mainMenu.getTopic2().getxCoord(),
mainMenu.getTopic2().getyCoord(), this);
G.drawImage(mainMenu.getTopic3().getspriteImage(),
mainMenu.getTopic3().getxCoord(),
mainMenu.getTopic3().getyCoord(),this);
/*Shows mouse input worked by changing the background color*/
if (State == GameState.MAINMENU_TOPIC1)
{
setBackground(Color.BLACK);
}
if (State == GameState.MAINMENU_TOPIC2)
{
setBackground(Color.BLUE);
}
if (State == GameState.MAINMENU_TOPIC3)
{
setBackground(Color.GRAY);
}
repaint(); //tells paint to repaint, which allows gui to update
}
#Override
public void mouseClicked(MouseEvent e)
{
Point point = e.getPoint();
/*This contains the logic to change State based on mouse clicks*/
if(mainMenu.getTopic1().getRectangle().contains(point))
{
State = GameState.MAINMENU_TOPIC1;
}
if(mainMenu.getTopic2().getRectangle().contains(point))
{
State = GameState.MAINMENU_TOPIC2;
}
if(mainMenu.getTopic3().getRectangle().contains(point))
{
State = GameState.MAINMENU_TOPIC3;
}
}
So, I am unsure why mouse clicks would not always be detected. I know there is a chance that the time allocated to update the action listeners could be too short. However, there is not very much code for the machine to loop through, so I figure this is not the problem. Any thoughts on what might cause the mouse to behave this way?
Also, I will definitely implement this later using JButtons. I am sure that would help clean up my code on the larger project
Thanks for the comments, and I hope this clears up the majority of the questions.

A mouse "click" may essentially be a double or triple click. You can get that by using evt.clickCount. It will coalite as one event.
If you want to get every "press", use mousePressed() instead.

Image does not immediately get replaced after calling repaint()+revalidate()

I'm making a game/simulator and I'm using the following method to load an Image into my current Java project:
public static Image getImage(String name) {
URL url = ImageLoader.class.getClassLoader().getResource("resources/" + name);
Image img = Toolkit.getDefaultToolkit().createImage(url);
ImageLoader.tracker.addImage(img, 1);
try {
ImageLoader.tracker.waitForID(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
return img;
}
This loads the images into my class that is drawing all items including the player (who has 4 different images for each direction he can face: north, south, east, west):
private Image player = ImageLoader.getImage("playerEast.png");
private Image playerEast = ImageLoader.getImage("playerEast.png");
private Image playerWest = ImageLoader.getImage("playerWest.png");
private Image playerSouth = ImageLoader.getImage("playerSouth.png");
private Image playerNorth = ImageLoader.getImage("playerNorth.png");
The class that loads above images paints them in the area like such:
public class TerritoryPanel extends JPanel implements Observer {
#Override
protected void paintComponent(Graphics g){
super.paintComponent(g);
//Draw player
g.drawImage(player, (x, y, this);
}
I'm trying to update the pics with this method in the same class:
public void rotateEast(){
player = playerEast;
repaint();
revalidate();
}
..but just calling this rotateEast() does not update the picture immediately, it only gets updated afterwards when my regular Observer update() cycle calls repaint(), this happens every second so the missing repaint of rotateEast is visible:
#Override
public void update(Observable o, Object arg) {
if (EventQueue.isDispatchThread()) {
this.repaint();
} else { // Simulation-Thread
SwingUtilities.invokeLater(new Runnable() {
#Override
public void run() {
repaint();
}
});
}
}
Why does the repaint() from rotateEast seem to have no effect? Thank you very much in forward

but just calling this rotateEast() does not update the picture immediately, it only gets updated afterwards when my regular Observer update() cycle calls repaint(),
Don't know if it will make a difference but the normal logic is:
revalidate(); // to invoke the layout manager
repaint(); // to repaint all the components
Even if it doesn't make a difference in this case this order you should always use when dynamically changing the property of a component including adding/remove components from a panel.

Calling repaint from another class JFrame

I'm trying to call repaint from another class. But it does not work. I have to draw on a frame.
public class Tester extends JFrame{
public static dtest d ;
public static void main(String[] args) {
Tester t = new Tester();
d = new dtest();
test tnew = new test();
}
public static class dtest extends JFrame implements MouseMotionListener{
public static int x,y;
dtest()
{
super("title");
setSize(500,500);
setVisible(true);
addMouseMotionListener(this);
}
#Override
public void mouseDragged(MouseEvent e) {
x = e.getX();
y = e.getY();
repaint();
}
#Override
public void mouseMoved(MouseEvent e) {
// TODO Auto-generated method stub
}
public void paint(Graphics g)
{
System.out.println("I am called");
}
}
public static class test {
public test()
{
for(int i = 0 ; i < 5 ; i++)
{
System.out.println("I am called from run");
d.repaint();
}
}
}
}
this prints
I am called from run
I am called from run
I am called from run
I am called from run
I am called from run
so it does not executing the paint() portion. d.repaint() is not working. why?

Take a look at this page and look at the first answer. It's a similar if not exact question to yours.
JFrame's paint() method has been deprecated. The compiler, or your IDE, should be complaining a bit, especially if you place the #Override tag directly above the method (use this to test if this method can be rewritten... aka what you're trying to do).
This means that its use has been discouraged and some functionality may have been removed. When using javax.swing, you'll want to learn the system completely about JPanels and JComponents. To paint something on a screen, you'll want to add a custom class that extends JPanel with the add(Component c) method. Then, override the paintComponent(Graphics g) method in that class. Make sure to have the first line in that method be super.paintComponent(g); so that the window can refresh itself.
For completeness:
public class MyWindow extends JFrame {
MyPanel thePanel;
public MyWindow(int x, int y) {
setSize(x, y);
thePanel = new MyPanel(x, y);
this.add(thePanel);
}
}
public class MyPanel extends JPanel {
public MyPanel(int x, int y)
setSize(x, y);
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawImage(ImageManager.getImage("Cute Puppy"), 40, 40, null); // Or whatever
}
}
So, when the repaint() or revalidate() method is called on the MyWindow, the Panel will recieve a paintComponent call.
Please let me know in the comments if you need any additional help.
Edited:
Since you need to use MouseMotionListener, and I'm still not quite understanding the context and trouble of "I need to call repaint from another class"... I will try my best.
Firstly, check out this tutorial on the Oracle pages. Also, check out the others on GUI's. You'll learn a lot about organization and displaying that will make you realize how their system can work with yours.
Now, for your questions:
i have to use MouseMotionListener.
Not quite... it is a good way for set up but you can run a Thread (something that constantly runs methods over and over) to check the Mouse coordinates. You'll want to start doing this when you get into games and other miscellaneous applications.
new Thread() {
public void run() {
Point mouse;
int mousex;
int mousey;
while (true) {
mouse = MouseInfo.getPointerInfo().getLocation();
mousex = mouse.x - theWindow.getLocationOnScreen().x - 3; // You'll need to get the
// x coordinate, subtract the window's x coordinate, and subtract 3 because of
// the blue border around a standard pc window.
mousey = mouse.y - theWindow.getLocationOnScreen().y - 29; // 29 is top bar height
SomeOtherClass.processMove(mousex, mousey);
}
}
}.start();
Next: I tried that with JPanel but i could not do that. If you read the tutorial at the top of my edit, you see they implement MouseMotionListener with ease.
Next: I prefer to do it with JFrame. If you wish to process the mouse in the JFrame, do the following: Have your JFrame the listener, but the JPanel be where the mouse data comes from. As follows:
public class MyWindow extends JFrame implements MouseMotionListener {
public MyPanel thePanel;
public int x;
public int y;
public MyWindow() {
thePanel = new MyPanel();
thePanel.addMouseMotionListener(this);
// Make this JFrame get called when the mouse
// moves across the panel.
}
#Override
public void mouseDragged(MouseEvent e) {
x = e.getX();
y = e.getY();
thePanel.repaint();
}
#Override
public void mouseMoved(MouseEvent e) {
// TODO Auto-generated method stub
}
}
public class MyPanel extends JPanel {
public void paintComponent(Graphics g) {
super.paintComponent(g);
// Other painting stuff
}
}
Next: Now i have to update the frame from another class. I could not find a way to update the GUI(the frame) from another class.
Simple. Since the JPanel is what needs to be updated, add the following method to the MyWindow class:
public void repaintWindow() {
thePanel.repaint();
}
And add this to whenever you need to update it:
MyWindow theWindow = new MyWindow();
theWindow.repaintWindow();
Next: all the answers here extended JPanel. So i could not find my answer.
I apologize, but you NEED a panel. It is possible to do with JFrames, but if you want to start doing things raw and low-level, you need to learn how these things work by learning to read the oracle tutorials and the oracle documentation. For now, use JPanels in any ways I've shown you.
Next: from another class I have to draw something on JFrame.Is that possible?
Yes, indeed! Whenever you want to draw something:
MyWindow theWindow = new MyWindow();
Graphics g = theWindow.thePanel.getGraphics();
BufferedImage someRandomImage = SomeRandomClass.getRandomImage();
g.drawImage(someRandomImage, 200, 481, null);
theWindow.repaintWindow();
I really hope I've helped but to program in java you need to use the tools they give you, especially when it comes to high level things like Swing. There are tutorials everywhere for this stuff. Please read them before asking for specific help in the future.

JPanel Repaint Not Clearing

I have a custom, abstract class 'Panel' which extends JPanel. There aren't many differences with the two when painting. I have a Panel and I'm simulating an animation by updating the x value of an image. I have two animations right now, one that properly repaints and another than does not. This is for the one that does not. The one that works will be labelled A, the one that doesn't will be B.
A and B follow the same format. Update some variable on the Panel, calls update (a method in Panel which calls PaintComponent) and then calls repaint. It calls repaint after because this issue was with A before and was solved that way.
A: Updates an image variable.
B: Updates the x variable of an image.
The Problem: The repaint doesn't clear the old image location and so it's a choppy mess across the screen.
What I've tried:
I've seen the super.PaintComponent(g) mentioned a lot, but this
hasn't solved the problem.
I've tried changing the order for when the repaint/update methods are
called.
Repaint does not update the Panel at all. (Probably because the
painting is done in PaintComponent)
Any help would be appreciated.
Code:
Panel:
public Panel (boolean visible){
super();
this.setLayout(new BorderLayout(640, 416));//sets the Layout type of the panel
this.setOpaque(false);//Makes it so that the panel underneath can be seen where images aren't drawn
this.setVisible(visible);
ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
gs = ge.getDefaultScreenDevice();
gc = gs.getDefaultConfiguration();
}
public void paintComponent (Graphics g){
setUp();
drawOff();
setDown(g);
}
private void setUp(){
off_screen = gc.createCompatibleImage(getSize().width, getSize().height, Transparency.TRANSLUCENT);
buffer = off_screen.createGraphics();
}
protected abstract void drawOff();
private void setDown(Graphics g){
g.drawImage(off_screen,0,0,this);
off_screen.flush();
}
public void update(){
paintComponent(this.getGraphics());
}
Animation Methods (mg is the panel in question):
private void battleStart(User user) {
for (int i = 0; i < user.battle.length; i++) {
mg.battleStart(user.battleStart(i));
mg.update();
try {
Thread.sleep(150);
} catch (Exception e) {
}
mg.repaint();
}
}
private void animateStart(User user){
for (int i = 0; i < 10; i++){
mg.x = mg.x + 10;
mg.update();
try {
Thread.sleep(100);
} catch (Exception e) {
}
mg.repaint();
}
}

I think your design is way off and that is why things are not working. I'm not quite sure how your non-abstract JPanels work, but consider making your parent JPanel something more along these lines:
import java.awt.*;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
public class MyPanel extends JPanel {
private GraphicsEnvironment ge;
private GraphicsDevice gs;
private GraphicsConfiguration gc;
private BufferedImage offScreen;
public MyPanel(boolean visible) {
super();
this.setLayout(new BorderLayout(640, 416)); // strange constants for this layout.
this.setOpaque(false);
this.setVisible(visible);
ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
gs = ge.getDefaultScreenDevice();
gc = gs.getDefaultConfiguration();
addComponentListener(new ComponentAdapter() {
#Override
public void componentResized(ComponentEvent e) {
setUp();
}
});
}
#Override
// don't make this public. Keep it protected like the super's
// just draw in this method. Don't call other methods that create buffers
// or draw to buffers.
protected void paintComponent(Graphics g) {
super.paintComponent(g);
if (offScreen != null) {
g.drawImage(offScreen, 0, 0, null);
}
}
private void setUp() {
offScreen = gc.createCompatibleImage(getSize().width, getSize().height,
Transparency.TRANSLUCENT);
}
// draw to the buffer outside of the paintComponent
// and then call repaint() when done
public void upDateOffScreen() {
// ?? offScreen.flush(); // I've never used this before,
// so am not sure if you need this here
Graphics2D osGraphics = offScreen.createGraphics();
// TODO: do drawing with osGraphics object here
osGraphics.dispose();
repaint();
}
}
Also and again,
Do all long processing methods off of the EDT (Event Dispatch Thread).
Never call Thread.sleep(...) on the EDT.
Consider using Swing Timers instead of using Thread.sleep for the animations.
It's OK to call repaint on your JPanel off of the EDT, but for the most part that's about it.
All other Swing methods should be called on the EDT.
Read, re-read, and study the 2D and Swing graphics tutorials.

why is paintComponent() never called by repaint()?

I've been working on an program that draws custom JComponents onto a JLayeredPane however all calls to repaint() on the components seem to do nothing yet the paintComponent method is invoked automatically when the window is re-sized.
I have been following some of the advice given here:
Why is paint()/paintComponent() never called?
But none of the solutions seem to fix my problem, update swing components on the EDT, setting component size manually before calling repaint(), calling super.paintComponent(g) in the overridden paintComponent() and calling revalidate() on the frame after adding new components (although this is clearly no the issue in this case)
Any ideas what could be stopping the call? Thanks in advance :)
Here is the code for the View and the SVGElementContainer, view.setFile() is the entry-point as it is invoked when a new document needs to be displayed.
public class View extends JLayeredPane implements SVGViewport {
private SVGDocument document;
//Array list of the SVGElementContainer components
private ArrayList<SVGElementContainer> elemContainers;
private SVGFrame frame;
private int elemCount;
private Border viewBorder;
private int borderWidth = 1;
//panels displayed on the JLayeredPane
private JPanel backgroundPanel;
/** Creates a new view */
public View(SVGFrame frame) {
super();
this.frame = frame;
elemCount = 0;
elemContainers = new ArrayList<SVGElementContainer>();
viewBorder = BorderFactory.createLineBorder(Color.BLACK, borderWidth);
}
public float getViewportWidth() {
return getWidth();
}
public float getViewportHeight() {
return getHeight();
}
// paints all elements and adds them to the JLayeredPane
public void paintAllElements(){
System.out.println("Painting all elements");
// Paint document
for (SVGElement elem : document) {
//only paint stylable (rect, line, circle) elements
if (elem instanceof SVGStylable){
//create a new SVGElementContainer
SVGElementContainer newElemCont = new SVGElementContainer();
//add component to JLayeredPane
elemCount++;
this.add(newElemCont, new Integer(elemCount + 1));
//set the current element within its container and calls repaint() on the component
System.out.println("Painting element #" + elemCount);
newElemCont.setElement(elem);
newElemCont.repaint();
}
else {
System.out.println("Skip painting group element!");
}
}
}
/** Gets the document currently being displayed by the view. */
public SVGDocument getDocument() {
return document;
}
/** Sets the document that the view should display.
*
* #param document the document to set
*/
public void setDocument(SVGDocument document) {
this.document = document;
//paintBackground();
paintAllElements();
revalidate();
}
public void revalidate(){
//calls validate() on the frame in order to display newly added components
frame.getContentPane().validate();
}
}
public class SVGElementContainer extends JPanel{
private SVGElement elem;
public SVGElementContainer(){
super();
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
System.out.println("PAINT METHOD CALLED!");
paint2D((Graphics2D) g);
}
//paint the element onto this JComponent
public void paint2D(Graphics2D g){
if (!(elem instanceof SVGStylable)){
System.out.println("Skipping non-stylable element!");
return;
}
setOpaque(false);
Shape shape = elem.createShape();
// get fill stroke and width properties
SVGStylable style = (SVGStylable) elem;
SVGPaint fillPaint = style.getFill();
SVGPaint strokePaint = style.getStroke();
SVGLength strokeWidth = style.getStrokeWidth();
// Fill the interior of the shape
if (fillPaint.getPaintType() == SVGPaint.SVG_PAINTTYPE_RGBCOLOR) {
g.setPaint(fillPaint.getRGBColor());
g.fill(shape);
}
// Stroke the outline of the shape
if (strokePaint.getPaintType() == SVGPaint.SVG_PAINTTYPE_RGBCOLOR) {
Stroke stroke = new BasicStroke(strokeWidth.getValue());
g.setStroke(stroke);
g.setColor(strokePaint.getRGBColor());
g.draw(shape);
}
}
public void setElement(SVGElement elem){
this.elem = elem;
setComponentSize();
}
private void setComponentSize(){
//this.setPreferredSize(new Dimension(
// (int)elem.getDocument().getWidth().getValue(),
// (int)elem.getDocument().getHeight().getValue()));
this.setSize(new Dimension(
(int)elem.getDocument().getWidth().getValue(),
(int)elem.getDocument().getHeight().getValue()));
}
}

I see that you're calling setOpaque(false). From the setOpaque javadoc, emphasis mine:
If true the component paints every pixel within its bounds. Otherwise, the component may not paint some or all of its pixels, allowing the underlying pixels to show through.
That "may" be the cause of paintComponent() not being called after the first time during a repaint() call. Swing can decide that the component has not "changed", and thus does not need repainting.

setting component size manually before calling repaint(), calling super.paintComponent(g) in the overridden paintComponent() and calling revalidate() on the frame after adding new components
Your code is wrong on these concepts.
a) never invoke the setSize() method. That is the job of the layout manager. You should be providing hints to the layout manager by overriding methods like getPreferredSize() to return the preferred size of your component
b) don't override the revalidate() method. The point of that tip is to use code like:
panel.add( .... );
panel.revalidate();
panel.repaint();
But I don't really know what all your code is supposed to do so I can't tell for sure if your code makes sense. I also find it strange that you are extending a JLayeredPane.

I can see extending JPanel to get the buffering and UI delegate, but the opacity is L&F dependent. Instead, you should probably start with JComponent and implement the EventListenerList plumbing for your (hypothetical) SVGEvent.