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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

Graphical Components

I have done a program that numerically solves a set of differential equations which describes how an "arbitrary" illness move in an isolated and constant population, it was a programming assignment from a class I took a while ago. What I've done to extend it is to add some graphical components that can pause, reset and "play" the simulation, as well as some components that allows me to change some constants in the equations.
All this was an exercise in programming as I find it to be fun and exciting and want to become better.
However, at the moment I'm stuck, what I want to do now is to make a very simple form of animation of it. I want to visualize the data I get for the number of infected, susceptibles and resistants in a grid as points. I managed to create the grid and have an idea of how to place the dots.
The problem I have is how to draw the dots as the program is working, I can draw one dot in the grid but only as the grid is created, that's it. I need to be able to create a dot at a specific place in the grid, this goes on until the number of dots reaches a finite number, say 30. At that points I want to have the first dot, the one the left, removed, all the dots shifted to the left and place the new dot at the furthest right of the grid, the whole thing is then repeated.
I think I will be able to figure it out with some help/hints about the paintComponent() method and whether I need to use repaint() method at all, I can't get my head around these for some reason. I've read through my course literature on Java, but despite the extensive sections where he explains most of the different graphical components he does not say that much about those methods, only that you don't call for the paintComponent() method, it is done automatically.
If there is something unclear let me know and I'll try to clarify it.
Thanks in advance.
//
Fox Mulder

I think I will be able to figure it out with some help/hints about the paintComponent() method and whether I need to use repaint() method at all, I can't get my head around these for some reason.
Basically, say you create a custom component by extending JPanel. When you #Override the paintComponent() method, it get implicitly called for you, so you never have to call it. So what ever you paint inside the method, gets drawn on your surface. For example
public class DrawingPanel extends JPanel {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.fillOval(x, y, 10, 10);
}
}
When you call repaint() you are basically causing the paintComponent method to be call implicitly. So to answer your question, Yes you will need to call it if you want to animate, as you will need to update some kind of variable (like the x and y) in the paintComponent() method, to see any change in the drawing.
You can see more at Performing Custom Painting
Not to handle the actual animation, you'll want to use a javax.swing.Timer. You can see more at How to use Swing Timers. Here's the basic construct
Timer ( int delayInMillis, ActionListener listener )
where delayInMillis is the time to delay between ticks(in this case animations) and the ActionListener listens for "ticks". Each tick, the actionPerformed of the ActionListener is called. There, you can put the code to update any variables you use for animation.
So for example you update the x and y, in the actionPerformed, then call repaint()
public class DrawingPanel extends JPanel {
int x = 50;
int y = 50;
public DrawingPanel() {
Timer timer = new Timer(40, new ActionListener(){
#Override
public void actionPerformed(ActionEvent e) {
x += 5;
y += 5;
repaint();
}
});
timer.start();
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.fillOval(x, y, 10, 10);
}
}
Now this was just a simple example. But in your case you want to animate a scatter plot. So what you can do is have a list of Points and in the actionPerformed you can add pull points from that list and push them into another list that is to be drawn. So say you have this
List<Point> originalPoints;
List<Point> pointsToDraw;
...
#Override
protected void paintComponent(Grapchics g) {
super.paintComponent(g);
for (Point point : pointsToDraw) {
g.fillOval(point.x - 5, point.y - 5, 10, 10);
}
}
Basically all the points in pointsToDraw list will be drawn. Initially it will be empty. And in the timer, you can add to the list, until the originalPoints list is exhausted. For example.
List<Point> originalPoints;
List<point> pointsToDraw;
private int currentIndex = 0;
public DrawingPanel(List<Point> originalPoints) {
this.originalPoints = originalPoints;
pointsToDraw = new ArrayList<>();
Timer timer = new Timer(40, new ActionListener(){
#Override
public void actionPerformed(ActionEvent e) {
if (currentIndex == originalPoints.size() - 1) {
((Timer)e.getSource()).stop();
} else {
pointsToDraw.add(originalPoints.get(currentIndex));
currentIndex++;
}
repaint();
}
});
timer.start();
}
So basicall you just keep a current index. When the index reaches the size of the original list, you stop the timer. Otherwise you just pop from the originalPoints and push to the pointsToDraw. For every point you add the pointsToDraw, a repaint() is called, and there will be another point for the paintComponent to draw a circle with.
The END
UDPATE
I just reread your question, and I think I have have misunderstood it. If you want all the points drawn, then basically just have one list. And draw all the points initially. with each tick, just remove the first index, advance all the rest up an index, and add a new one to the end. Though this is the implementation of a LinkedList so you may just want to use that

JButton not working for me?

I am making a program where you choose a selection sort or a merge sort using JButtons and it sorts an int array in the form of a bar graph using Graphics where each element in the array is a bar.
but for some reason the compiler isn't receiving my button presses, i have tried to use
(selection.equals(e.getSource()) in the if statement but it isnt working, am i missing something obvious or what?
public class Animation extends Canvas implements ActionListener{
JPanel panel;
JButton Selection;
JButton Merge;
boolean selection, merge;
int[] random = new int[25];
Sorter sort = new Sorter();
public Animation(){
Selection = new JButton("Selection sort");
Selection.addActionListener(this);
Selection.setActionCommand("select");
Merge = new JButton("Merge sort");
Merge.addActionListener(this);
Merge.setActionCommand("merge");
panel = new JPanel();
panel.add(Selection);
panel.add(Merge);
setBackground(Color.WHITE);
selection=false;
merge=false;
}
public void actionPerformed(ActionEvent e) {
if("select".equals(e.getActionCommand())){
selection = true;
repaint();
}
else if("merge".equals(e.getActionCommand())){
merge = true;
repaint();
}
}
public void paint (Graphics window){
Random r = new Random();
for(int i=0; i<random.length; i++){
int randomInt = r.nextInt(100) + 1;
random[i] = randomInt;
}
window.setColor(Color.MAGENTA);
if(selection==true){
for(int i=0; i< random.length-1; i++){
int smallest = i;
for(int j = i+1; j< random.length; j++){
if(random[j] < random[smallest])
smallest = j;
}
if( smallest != i) {
int least = random[smallest];
random[smallest] = random[i];
random[i] = least;
drawIt(random, window);
window.setColor(Color.WHITE);
drawIt(random, window);
window.setColor(Color.MAGENTA);
}
}
}
drawIt(random, window);
}
public void drawIt (int[] a, Graphics window1){
int x=128;
int height = 200;
for(int i=0; i<a.length; i++){
window1.drawLine(x, 200, x, height-a[i]);
window1.drawLine(x+1, 200, x+1, height-a[i]);
window1.drawLine(x+2, 200, x+2, height-a[i]);
x+=20;
}
try {
Thread.currentThread().sleep(100);
} catch(Exception ex) {
}
}
}
heres the main class to run it:
public class AnimationRunner extends JFrame{
private static final int WIDTH = 800;
private static final int HEIGHT = 250;
JButton Selection;
JButton Merge;
public AnimationRunner()
{
super("Sorting Animation");
setSize(WIDTH,HEIGHT);
Animation a = new Animation();
Merge = new JButton("Merge sort");
Selection = new JButton("Selection sort");
Merge.setSize(120, 30);
Selection.setSize(120,30);
Merge.setLocation(200, 30);
Selection.setLocation(400, 30);
this.add(Merge);
this.add(Selection);
((Component)a).setFocusable(true);
getContentPane().add(new Animation());
setVisible(true);
}
public static void main( String args[] )
{
AnimationRunner run = new AnimationRunner();
}
}

You create a button for each action in your main class and add these to your JFrame. You also create a two instances of your Animation class. One which you create, setfocusable then do nothing with. Then another which you create and add to the contentPane of the JFrame.
In your Animation constructor you again create a button for each action, this time setting the action commands. You then add these to a panel. This panel is never added to anything and so these buttons will never be seen.
The buttons you see are not the buttons that you have defined the action commands for.
Also you should avoid using setSize() and Use Layout Managers to defines the sizes of your components.

There are a series of cascading problems...
In the AnimationRunner class you create two JButtons called Merge sort and Selection sort and add these to the main frame. This is what's actually on the screen. This buttons have no listeners attached, therefore never notify any body when they are clicked...
In the Animation class you create two JBttonss called Merge sort and Selection sort and add these to panel (and instance of JPanel), which is never added to anything. This means you can never possibly click them...
You don't seem to have an understanding of how painting works in Swing and seem to be assuming that you control the paint process in some way.
Painting is controlled by the paint sub system in Swing, which schedules and performs paint cycles when and where it sees fit. This means that your paint method may be called for any number of reasons, many of which you don't control.
Remove the logic of the sort out of the paint process and place into some kind of model, whose state you can control. Then use the custom painting capabilities to render the state of the model.
paint is an inappropriate method to be using for custom painting and you should be using paintComponent. You have broken the paint chain which may prevent the component from rendering child components and/or introduce series paint artifacts into your program
Take a look at Performing Custom Painting and Painting in AWT and Swing for more details
Swing is a single threaded framework work. That means that anything that blocks the Event Dispatching Thread will prevent it from process new repaint requests or events into the system. This will cause your program to look like it's "hung". In your case, you will most likely only ever see the end result of the painting process...after a short delay.
Instead, consider using a javax.swing.Timer to introduce a safe delty and update the model each time it ticks.
Take a look at Concurrency in Swing and How to use Swing Timers for more details
Swing programs are expected to run on a variety of hardware and software platforms, all with there own notions of DPI and font rendering approaches. This makes it very difficult to accommodate your design to all the possible needs of these systems.
Swing makes this easier by providing a layout management API, which takes the fiddle work out of making these decisions. Take a look at Laying Out Components Within a Container for more details
You should also take a look at Code Conventions for the Java Programming Language, it will make it eaiser for people to read your code.
You might find this example of some benifit

creating new jpanels using loop

i creating new jpanels using loop. but how i using different object name.
here is my code:
for(int i=0; i<panelnumbers.length(); i++){
MainConfig.page21.addNewPanel(MainConfig.page21.pos1, "INFORMACIÓN No. " + (i + 2));
}
public static void addNewPanel(int y, String title) {
Add a = new Add(title);
jLayeredPane3.add(a);
a.setBounds(0, y, 1333, 450);
jPanel1.setPreferredSize(new Dimension(1333, (pos + 480)));
jLayeredPane3.setPreferredSize(new java.awt.Dimension(1333, (pos + 480)));
jLayeredPane3.validate();
jScrollPane1.getViewport().setViewPosition(new Point(0, (pos + 480)));
}

i creating new jpanels using loop. but how i using different object
name.
use JPanel.get/putClientProperty,
you can to multiply this method
every events this/these value, e.g. from Listeners
for example

You are using absolute coordinates, a layout manager gives a better GUI across platforms, later Windows versions, accessibility etcetera.
MainConfig.page21.setLayout(new BoxLayout(MainConfig.page21, BoxLayout.Y_AXIS));
Also normally one would not need the JPanel, an event listener would know how to retrieve the panel.
Nevertheless you could maintain an array of JPanels:
List<JPanel> panels = new ArrayList<>();
In addPanel create a local variable, and add that
public void addNewPanel(int y, String title) { // Not static
JPanel panel = new JPane();
...
panels.add(panel);
}

Collecting data from a large number of Swing text fields

I am currently writing a sudoku solver in Java. What I need now is some kind of Swing GUI to input the known numbers. I created a JFrame, but manually adding 81 text fields from the toolbox seems like a bad solution. I am also able to add with code like this:
this.setLayout(new GridLayout(9, 9));
for (int i = 0; i < 81; i++)
{
this.add(new JTextField("Field"));
}
However, I do not know how to address these text fields afterwards to collect the user input into a two-dimensional array. How can I do that?

A different solution would be to use a JTable. You could allow for the TableModel to maintain the full data solution, as well as a copy of the user's attempts. The CellRenderers and CellEditors could handle the user experience. See this tutorial.

Struggled a bit with this for my own sudoku solver, but ended up going for painting on a JPanel, and adding a mouse listener to that.. Than determine the current field using mouse position with his function:
addMouseListener(new MouseAdapter() {
private int t(int z) {
return Math.min(z / factor, 8);
};
#Override
public void mouseMoved(MouseEvent e) {
setToolTipPossibilities(t(e.getX()), t(e.getY()));
}
#Override
public void mousePressed(MouseEvent e) {
clickColumn = t(e.getX());
clickRow = t(e.getY());
}
});

First you need to declare array of JTextFields.
So just like your array to store user input you do:
private JTextField[] textFields;
After that you can use some math to map your one-dimensional array to your two dimensions.
something like this should work:
floor(index / 9), index % 9
for x,y

Yes that will work to display the array. To read from the array you just need to call the getText method for each element.

JTable is your friend. Use a DefaultTableModel with editable String values.
String[] columnNames = new String[9];
for(int i=0; i<9; i++){columnNames[i]="";}
String[][] data = new String[9][9];
JTable tab = new JTable(columnNames,data);
When they fill it in, check that each string is an appropriate number and prompt for error.

1st way:
You could put the text fields into an array that mirrors the array that your cell values are in.
The problem with this method tho is that when you need to bind a mouseListener or ActionListener to the TextField you will have a hard time figuring out which cell number it corrisponds to.
2nd way:
You could extend the JTextField into a custom class with new instance variables that store cell number in it.
Using this method you can also implement MouseListener or ActionListener on the extended class too and get whatever information about the field you need, without searching through your array. And combining with the first to put them into an array organizes them for quick access.

Just want to post a little update.
I added an array of textfields as a field on my form:
private JTextField[] fields;
Initialized it:
fields = new JTextField[81];
And finally I am adding the fields to my form like this:
private void addComponents()
{
this.setLayout(new GridLayout(9, 9));
for (int i = 0; i < fields.length; i++)
{
fields[i] = new JTextField("" + i);
this.add(fields[i]);
}
}
The result as of now can be seen here:
Image of my textfields