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How to make buttons on Java Swing Application when constantly redrawing frames

The simple version is that I'm drawing Graphics2D 60 times a second on a JPanel and it uses the drawstring method to create a bunch of labels. How would I go about making so I can click on those labels and have something happen?
Explanation: As it currently stands I have a system setup that says for every object in the world draw a string to the side (So I can see a list of all objects in the world). This is done with a for loop and the Graphics2D drawstring method.
The JPanel is being updated 60 times a second so this is being redrawn 60 times a second. I want to be able to click on these object labels so I can select the items, how would I go about turning them into buttons?
I messed around with JButton for awhile but it didn't seem to do me any good because whenever I added it the JPanel would go blank and only the button would render (Plus it didn't render to the right size).
More Details:
I use a
for(int I=0; I < sceneObjects.size(); I++) {
}
loop to grab every object in an object ArrayList. Each object has a String variable "Name". Before the loop class I sent an int called YPosition, and for every object the YPosition goes up by 20 so that the labels don't all stack on top of each other. I'm using the g2d.DrawString method to achieve this. But I need to be able to select the object labels.
I apologize if I forgot something in my question, let me know.
For those who are curious, the code looks exactly like this (Can't be compiled as is):
g2d.setFont(new Font("Arial", Font.PLAIN, hierarchyWidth / 26));
g2d.setColor(Color.black);
int oYPos = 20;
// For every object in existence
for(int i=0; i < engine.sceneObjects.activeObjects.size(); i++) {
GameObject theObject = engine.sceneObjects.activeObjects.get(i);
// If the scrollbar is within range of the hierarchy
// (Based on HierarchyHeight so that it's resolution friendly)
if(oYPos >= hierarchyScroll && oYPos < hierarchyScroll + hierarchyHeight) {
// If the object has no parent
if(theObject.transform.parent == null) {
g2d.drawString(theObject.name, hierarchyPosition.x + 5, hierarchyPosition.y + oYPos);
} else { // If the object has a parent
}
}
oYPos += 20;
}
// Track the last oYPos so that the scrollbar can adjust itself accordingly
lastOYPos = oYPos;
My guess would be some sort of class create for each of these labels and a Boolean stored called isSelected, and then rendering the label according to the class, but this seems a bit more complicated than I'd like to do

How do you embed a resizable JPanel inside of a JTextPane?

There are many questions of the converse, inserting a JTextPane into a JPanel. This is not my question. I need to be able to insert a custom JPanel (with drag and drop, drag, and mouse click listeners) into a JTextPane, which is then put into a JScrollPane, and finally put into a JFrame for displaying. The reason is because I need to have an image with support for resizing by dragging it within a chat client, which is itself primarily text.
Conveniently enough, there is a relevant method in JTextPane: insertComponent(Component c), but whenever I use it, my components end up being squished to exactly one line of text worth of space (even though they report having a larger size). This is perfect for plain buttons, but if I need anything larger, I'm out of luck. I can insert images by themselves just fine, with ImageIcons, but images wrapped inside a JPanel don't work at all (plus I can't add any listeners to ImageIcons, since they're not GUI elements; overriding one isn't an option).
Whenever a user drags an image into the chat client, this bit of code inserts the custom JPanel:
private void sendImage(BufferedImage im, int cl) throws IOException {
if(output == null) return;
//Send the image itself over to your friend
byte[] toSend = toBytes(im, cl);
sendString(nickname.hashCode() + "image"); //Header for image
output.writeInt(toSend.length); //Tells how many bytes to read.
output.write(toSend);
//Let the user know that the image was sent
float linmb = (float)(toSend.length / 1048576.0); //Size of file sent
addText("\n" + nickname + " sent an image! (" + linmb + " MB)\n", Color.RED.darker());
//Show the image itself
DraggerPanel d = new DraggerPanel(im, true);
text.insertComponent(d);
d.repaint();
//Spacer
addText("\n");
}
This is the source for DraggerPanel, the custom JPanel that holds an image:
public class DraggerPanel extends JPanel {
private BufferedImage image; //The image we're drawing
private Point startingPoint = null; //Starting point for resizing
private boolean first = true; //Is this the first drag?
private boolean lockedDrag; //If true, then lock x and y to be proportionally dragged.
public DraggerPanel(BufferedImage image, boolean lockedDrag) {
super();
this.image = image;
this.lockedDrag = lockedDrag;
//The listener for dragging events.
addMouseMotionListener(new MouseMotionListener() {
private int inWidth = 0, inHeight = 0; //Initial height and width values
private double ratio = 0; //Ratio of height to width for locked drag.
public void mouseDragged(MouseEvent m) {
if (first) { //If we're first, record initial position.
startingPoint = m.getPoint();
first = false;
inWidth = getWidth();
inHeight = getHeight();
ratio = (double)inHeight / inWidth;
} else { //Otherwise, change the size of the window.
if (!lockedDrag) {
int w = (int)startingPoint.getX() - m.getX();
int h = (int)startingPoint.getY() - m.getY();
setSize(Math.abs(inWidth - w), Math.abs(inHeight - h));
} else {
int w = (int)startingPoint.getX() - m.getX();
int h = (int)((double)ratio * w);
setSize(Math.abs(inWidth - w), Math.abs(inHeight - h));
}
}
repaint();
}
public void mouseMoved(MouseEvent m){
}
});
//Lets us know when you're not dragging anymore.
addMouseListener(new MouseAdapter(){public void mouseReleased(MouseEvent m){first = true;}});
//Set appropriate size.
if(image != null) setSize(image.getWidth(), image.getHeight());
else setSize(200,200);
//We're live, baby.
setVisible(true);
}
public void paint(Graphics g) {
if (image == null) super.paint(g);
else g.drawImage(image, 0, 0, getWidth(), getHeight(), null);
}
}
Update 1: I followed #camickr 's advice, and updated the DraggerPanel to use setPreferredSize instead of setSize, as well as overrode paintComponent() instead of paint(). Now, the image has the proper height, but is stretched to the width of the JTextPane (which seems like what it was doing before). Furthermore, resizing doesn't seem to matter- the image doesn't change its size at all. Mouse events are definitely going through, but not affecting the size. It seems as though the original problem isn't fully resolved, since the JPanel's size isn't what I need it to be, and the solution to that will also lead to a solution to the resizing issue.
Update 2: I did it! I finally did it. To the future time travelers who have this issue, I basically yelled at the JTextPane by not only using setSize() in my overridden JPanel, but also setPreferredSize() and setMaximumSize(). The preferred one works well with height, and the maximum sets the width (God knows why). Thanks for your tips, #camickr!

my components end up being squished to exactly one line of text worth of space (even though they report having a larger size).
I would guess the size is not important.
I would think you need to override the getPreferredSize() method of your DraggerPanel to return the preferred size of the panel so the text pane can display the panel.
Also, custom painting is done by overriding the paintComponent(...) method NOT the paint() method.

JtextPane with a touch interface

I'm developing a touch based windows 7 app using a tuio client-server setup and a touch library that extends multitouch 4 java.
One of the functionality I'm struggling with is to enable text highlighting when using touch.
I display a simple txt file using a JTextPane to display the text, the highlighting is done by through a drag action.
I get the clicked position where the drag event starts and then when it stops and tried to convert those coordinates to the text panel's space but I get different values from the ones that I should have, usually before the actual text.
The code I'm using to display the document is the following:
//Create the JDialog that is the container of it
window = new JDialog(parent);
window.setUndecorated(true);
//Create the JTextPane
text = new JTextPane();
text.setPage(newFile.toURI().toURL());
text.setEditable(false);
text.setHighlighter(null);
//ScrollPane that will be used to display the text
JScrollPane scroll = new JScrollPane(text);
scroll.setPreferredSize(new Dimension(500, 700));
window.getContentPane().add(scroll, BorderLayout.CENTER);
window.pack();
window.setVisible(true);
window.validate();
Where the JDialog parent is the main display component used in my app.
The drag is handled as follows:
#Override
public boolean processGestureEvent(GestureEvent ge) {
if((ge instanceof DragEvent) && this.component.isHighlight())
{
tapCount=0;
if(this.component.isHighlight())
{
//do highlighting
DragEvent drag = (DragEvent) ge;
switch (drag.getId()) {
case GestureEvent.GESTURE_STARTED:
Point start = drag.getFrom();
Point calcStart = new Point(start.x - compPosition.x, start.y - compPosition.y);
startPos = this.textDisplay.viewToModel(calcStart);
break;
case GestureEvent.GESTURE_ENDED:
Point end = drag.getTo();
Point calcEnd = new Point(end.x - compPosition.x, end.y - compPosition.y);
endPos = this.textDisplay.viewToModel(calcEnd);
System.out.println("I have this positions:" + startPos + "/" + endPos);
System.out.println("Should have " + this.textDisplay.getSelectionStart() + "/" + this.textDisplay.getSelectionEnd());
System.out.println("And the text is: " + this.textDisplay.getText().substring(startPos, endPos));
break;
case GestureEvent.GESTURE_CANCELED:
startPos = 0;
endPos = 0;
break;
}
}
return true;
}
In which the compPosition is the JDialog's position that holds the text pane. I'm simulating touch with the mouse so the correct text position for the highlighting I'm getting from the built-in highlighting functionality of the text pane with mouse.
Is the problem because of the JDialog and the JScroll pane that somehow skews the conversion?
The coordinate system for the point's I get from the touch are with the origin in the top left corner of the screen and the text pane's coordinate system origin is in the same top lef corner.
Any ideas on how can I solve the problem? Any suggestions are appreciated.
LE:
I was doing something wrong in that I was adding the gesture processor when I initialized the component and it's position was (0,0) and only afterwards I moved it where I wanted to.
I changed the position calculations as follows:
Point calcStart = new Point(start.x - this.component.getLocation().x, start.y -this.component.getLocation().y);
passing instead a reference to the actual component and getting the location when needed.

try instead of
Point calcStart = new Point(start.x - compPosition.x, start.y - compPosition.y);
to use
Point calcStart = new Point(start.x, start.y);
i wonder how it gonna end, so give us some value of what you get

JAVA Background Animation (LinearGradientPaint)

A LinearGradientPaint object from java.awt may appear nice once painted, but there's a problem I'm having with it for painting an animated background in some kind of game model that's taking me long to build.
I want to paint an animated rainbow gradient on the background using the Graphics2D paint object, except that when I do so, I notice a lot of lag in repainting the panel. It should repaint itself at least 30 frames per second, which is only possible if the Paint object the graphics object uses is not a rainbow gradient.
Even running it as a separate thread will not do the trick. Below is the code for what I am trying to do at the end of each frame:
gamePanel.executor.execute(new Runnable(){
public void run()
{
while(true)
{
if (Background.selectedBackgroundIndex >= Background.SKY_HORIZON_GRADIENT_PAINT &&
Background.selectedBackgroundIndex < Background.SPACE_PAINT)
{
float displacementValue = 1.0f;
if (Background.backgroundShape.y < ((-2990.0f) + CannonShooterModel.gamePanel.getSize().height) && gamePanel.horizonGoingDown)
gamePanel.horizonGoingDown = false;
else if (Background.backgroundShape.y > (-10.0f) && !gamePanel.horizonGoingDown)
gamePanel.horizonGoingDown = true;
Point2D.Double startPoint = (Point2D.Double)(((LinearGradientPaint)Background.background).getStartPoint()),
endPoint = (Point2D.Double)(((LinearGradientPaint)Background.background).getEndPoint());
if (gamePanel.horizonGoingDown)
Background.backgroundShape.y -= displacementValue;
else
Background.backgroundShape.y += displacementValue;
startPoint.setLocation(0, Background.backgroundShape.y);
endPoint.setLocation(0, Background.horizonGradientPaintHeight + Background.backgroundShape.y);
// Should be done in another thread, particularly in arithmetic calculations.
Background.background = new LinearGradientPaint(startPoint, endPoint,
((LinearGradientPaint)Background.background).getFractions(),
((LinearGradientPaint)Background.background).getColors());
}
for (int a = 0; a < PlayerUnit.weapon.bullets.length; a++)
{
if (PlayerUnit.weapon.bullets[a] != null)
{
if (PlayerUnit.weapon instanceof Pistol &&
((Ellipse2D.Float)PlayerUnit.weapon.bullets[a]).x + ((Pistol)PlayerUnit.weapon).bulletWidth >= 0 &&
((Ellipse2D.Float)PlayerUnit.weapon.bullets[a]).x <= CannonShooterModel.gamePanel.getSize().width &&
((Ellipse2D.Float)PlayerUnit.weapon.bullets[a]).y + ((Pistol)PlayerUnit.weapon).bulletWidth >= 0)
{
if (PlayerUnit.weapon.weaponAngles[a] >= 0)
((Ellipse2D.Float)PlayerUnit.weapon.bullets[a]).x +=
PlayerUnit.weapon.bulletSpeed * Math.cos(PlayerUnit.weapon.weaponAngles[a]);
else
((Ellipse2D.Float)PlayerUnit.weapon.bullets[a]).x -=
PlayerUnit.weapon.bulletSpeed * Math.cos(PlayerUnit.weapon.weaponAngles[a]);
if (PlayerUnit.weapon.weaponAngles[a] >= 0)
((Ellipse2D.Float)PlayerUnit.weapon.bullets[a]).y -=
PlayerUnit.weapon.bulletSpeed * Math.sin(PlayerUnit.weapon.weaponAngles[a]);
else
((Ellipse2D.Float)PlayerUnit.weapon.bullets[a]).y +=
PlayerUnit.weapon.bulletSpeed * Math.sin(PlayerUnit.weapon.weaponAngles[a]);
}
else
PlayerUnit.weapon.bullets[a] = null;
}
}
//System.out.println(Background.backgroundShape.y);
repaint();
try
{
Thread.sleep(1000 / 60);
}
catch (InterruptedException ex)
{
}
}
}
});
The classes Background, PlayerUnit, and CannonShooterModel are important to my game model. It's an upright shooting game supposed to be designed with various weapons and enemies.
This rainbow gradient I have uses an array of eight different Color objects. For every frame passed through, I change the y-coordinate for both Point2D.Float objects required for the gradient paint as desired. In order for the animation to work, I have to actually instantiate another object of LinearGradientPaint again, with some of the previous properties from the previous object, and have it be referenced by the variable background of type Paint.
Problem is, LinearGradientPaint does not have a method to where you can do a translate on the two end points, and the get methods do not return the actual object that LinearGradientPaint object contains. (what I mean is, the get methods return a new object of Point2D with the same values as those part of the LinearGradientPaint object.)
For every frame passed, I have to change not only the y-coordinate property of the shape that's associated with the gradient, but also set the locations of the two Point2D objects that are needed to instantiate LinearGradientPaint once again.
I would love to re-explain this much simpler, because I can have trouble with some knowledge of English, even though this is my primary language. Please let me know if you need re-explanation.

There are a couple of solutions you might try.
Instead of filling the entire paintable area, you could create a BufferedImage whose width is 1 pixel and height equal to the area you want to fill (assuming you are fill vertically). You would then apply the LinearGradientPaint to this BufferedImage's Graphics2D and fill it (don't forget to dispose of the Graphics context when your done).
Then, you would simply use Graphics#drawImage(Image, x, y, width, height, ImageObserver) to actually paint the image. Generally speaking, it appears that it's faster to rescale an image then it is to fill it with a LinearGradientPaint, especially when you consider you are only stretching the image horizontally.
The other choice would be to generate a basic BufferedImage which had the LinearGradientPaint already applied and you would simply paint this offset as required. This would probably require you to paint it at least twice to allow it to "stitch" toegther...

If you are just making the background gradient move up and down, could you write it to an image at initialization and then move and wrap the image vertically?

Swing, Java and multithreading, and coloring buttons

Yes, this is homework. Yes, I am completely stuck.
Here is the gist. I have created a JFrame. There are 3 panels (top, middle, bottom). In the bottom panel are 3 buttons called: Red, Green, and Blue. In the top Panel are 3 text fields that give us the number of times we have clicked the respective button. The max we are allowed is 10 for each button. In the middle Panel is an 8 x 8 grid of Jbuttons numbered from 0 to 63. So far, so good.
Every time we click a button, a thread starts. No thread ever dies When a thread starts, a number from 0 to 63 is randomly chosen. The JButton corresponding to that number is painted the color that was clicked on. So if the red button was clicked, we should see a box with a white background turn red. But then the color of that JButton starts to fade until it becomes white. The process should take about 8 seconds.
Threads that you create should not have access to any Swing components. Rather, one has to maintain a data structure and update by threads according to their cycle of execution. On the other hand, periodically invoke repaint() methods from main thread to invite Swing Event Dispatcher thread to eventually visit the content of the data structure and display the GUI components accordingly.
........ I have gotten all the objects created and displayed. You can't click more than 10 times on a button. Here is where I am:
I have two arrays: one is an array of strings with size 64. They represent the buttons. I also have an array of ints. This is so that I know the order by which the threads were created. I have created the threads as a button is clicked, and I have started them. Here is my run method for the threads:
public void run() {
Random num = new Random(new Date().getTime());
while (true) {
Thread j = Thread.currentThread();
int randInt = num.nextInt(64);
synchronized (lock) {
if ((array[randInt].compareTo("red") == 0
|| array[randInt].compareTo("blue")
== 0 || array[randInt].compareTo("green") == 0))
{
randInt = num.nextInt(64);
}
for (int k = 0; k < 10; k++) {
if (threadarray[k] == -1) {
threadarray[k] = randInt;
break;
}
}
}
}
}
Even though we haven't covered it, I have tried to use a Timer object that immediately goes off right outside of the lock section. This takes me to the actionPerformed method. I have added all the appropriate registration.
public void actionPerformed(ActionEvent arg0) {
for (int i = 0; i < threadarray.length; i++) {
int num = threadarray[i];
if (num != -1) {
System.out.println(num);
String s = array[num];
System.out.println(s + "is ");
if (s.compareTo("red") == 0) {
button[num].setOpaque(true);
button[num].setBackground(Color.red);
while (button[num].getBackground() != Color.white) {
System.out.println("not white yet");
int g = button[num].getBackground().getGreen();
int b = button[num].getBackground().getBlue();
if (255 - (g + 1) >= 0) {
Color c = new Color(255, g + 1, b + 1, 1);
button[num].setOpaque(true);
button[num].setBackground(c);
System.out.println(c + " " + " c is");
} else {
button[num].setBackground(Color.white);
}
}
}
System.out.println(i + " i is " + button[num].getBackground()); //just some debugging info
threadarray[i] = -1; //clear the thread array
array[num] = "0"; //clear the string array
}
}
}
The actionPerformed method is handled by the Event Dispatch Thread. (Note the code immediately above is for the red threads only. The idea is to fade the color by inclemently increasing the green and blue colors till it becomes white.
Problems: no button ever changes color when I click the red button on bottom (yes, appropriate registration has been done.) I also have no idea how to control the timing with a multitude of threads going. Am I even going down the right road here?

Without giving away too much, this example illustrates a way to deal with color and buttons that ignore setBackground(). Examples here and here demonstrate how to fade the color. As both rely on a javax.swing.Timer thread, neither is a solution, but the techniques may prove useful.