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memory game java gui

I'm trying to write a logic in memory game that when I click on cards and they are not a pair (different ID), program should swap them back after 1s. If they are same, then leave them as they are.
The problem is that when I first click and the card appears, after second clicking on another (different) card it doesn't appear and swap the first card after 1s. someone knows why the second card does not appear after clicking?
Btw when the pair is correct, everything works fine, here is my fragment of the code responsible for that logic in listener:
final int copy = i;
card2.addActionListener((e) -> {
card2.setIcon(new ImageIcon(icons[copy].getAbsolutePath()));
if(firstClick == null)
{
firstClick = (Card)e.getSource();
}
else
{
Card secondClick = (Card)e.getSource();
if(firstClick.getID() != secondClick.getID())
{
try
{
Thread.sleep(1000);
} catch (InterruptedException e1)
{
//e1.printStackTrace();
}
firstClick.setIcon(new ImageIcon(background.getAbsolutePath()));
secondClick.setIcon(new ImageIcon(background.getAbsolutePath()));
firstClick = null;
}
else
firstClick = null;
}
});

While method actionPerformed is executing, the GUI cannot react to mouse and keyboard events, so basically your code is "freezing" your GUI for one second. I believe that the class javax.swing.Timer is what you need and at first glance it looks like the duplicate question that MadProgrammer referred to may help you.

How to handle event in a program running in a cycle (loop)?

I´ve been dealing with this for some days now I´ve serach over the internet and tried everything that came up to my mind but nothing works. My problem is that I am making a pexeso game, we have some additionaly library directly from school or something like that which allows us to draw some pictures instead of comad line only... (We didn´t have graphics yet) So my problem is that my game is running in cycle and waiting for my click som I am checking the condition if click was made. And if I want to click I have to have just a method public void vyberSuradnice(int, int) declared in my code.
So the problem is that my game is runinng in cycle and checking if click was made. But when the click was made the method vyberSuradnice is executed and there I am setting the value off atrrbiute - cakatNaKlik on false, so click was made and one step of game can be made.. But since the function is running in cycle, then even If I clicked and in the method vyberSuradnice the value of attribute is changed, my function which is running in cycle isn´t respond to that change, so the game isn´t going on.
this is the method for clicking
public void vyberSuradnice(int paSuradnicaX, int paSuradnicaY) {
this.riadokOdkry = (paSuradnicaY ) / 25;
this.stlpecOdkry = (paSuradnicaX - 10) / 25;
if (this.riadokOdkry > this.aPocetRiadkov || this.stlpecOdkry > this.aPocetStlpcov) {
System.out.println("Klikli ste mimo hracieho pola ");
} else {
this.cakatNaKlik = false;
}
}
This the part of code where I am waiting for cakatNaklik - false value
while (uhadol) {
if (!this.cakatNaKlik) {
if (this.pocetUhadnutych >= (this.aPocetRiadkov * this.aPocetStlpcov) / 2) {
uhadol = false;
}
this.hraciaPlocha[this.riadokOdkry][this.stlpecOdkry].setUhadnute(true);
But even if the value is changed in method vyberSuradnice this condition is not triggered. But when I make something like this :
while (uhadol) {
System.out.print(this.cakatNaKlik);
if (!this.cakatNaKlik) {
if (this.pocetUhadnutych >= (this.aPocetRiadkov * this.aPocetStlpcov) / 2) {
uhadol = false;
}
this.hraciaPlocha[this.riadokOdkry][this.stlpecOdkry].setUhadnute(true);
the game is working like by writing the variable refresh it or something... but I am getting neverending print of true true or false on command line and this is something I can´t afford to have...
I know this may can be dan by threads but it´s something I can´t allowed to make and I am basically trying to do two things at once.
Is there any other to do this that the variable will be refreshed even without that println and the code will work ?
Thanks very much for every help

Thanks everybody for help, I finally solved it. I just tried tu put a sleep before the if condition. It only need to sleep for even a one miliseconds and it´s seems that the condition is refreshed so it works.

Try this:
Implement an ActionListener interface or extend a class that implements an ActionListener interface. For example:
public class MyClass implements ActionListener {
}
Register an instance of the event handler class as a listener on one or more components. For example:
someComponent.addActionListener(instanceOfMyClass);
instanceOfClass = this; //(if it is handled in the same Class)
Include code that implements the methods in listener interface. For example:
public void actionPerformed(ActionEvent e) {
...//code that reacts to the action...
}
Reference:
https://docs.oracle.com/javase/tutorial/uiswing/events/actionlistener.html

Turns issue in java game [closed]

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I've created a simple game which a player plays against computer.
I've got an issue in the timing of the turns, the computer should be the first to make a move than the real player should make his move by clicking LeftChoice or RightChoice button.
Here's my problem at code:
public class GameForm extends javax.swing.JFrame {
/**
* Creates new form GameForm
*/
final int SIZE = 10;
int CurrentSize = 10;
int PC_SUM=0;
int HUMAN_SUM=0;
boolean PC_TURN = true;
int[] RandArr = new int[SIZE];
public GameForm() {
initComponents();
}
public void init(){
for(int i = 0 ; i<SIZE;i++){
RandArr[i] = (int)(Math.random()*100)+1;
}
jTextField3.setText("");
jTextField4.setText(Integer.toString(PC_SUM));
jTextField5.setText(Integer.toString(HUMAN_SUM));
}
public void HUMAN_updateLeft(){
HUMAN_SUM+=RandArr[0];
jTextField5.setText(Integer.toString(HUMAN_SUM));
jTextField1.setText(Arrays.toString(RandArr));
CurrentSize--;
int [] NewRand = new int[CurrentSize];
for(int i = 1 ; i<=CurrentSize;i++){
NewRand[i-1] = RandArr[i];
}
RandArr = NewRand;
jTextField2.setText(Arrays.toString(RandArr));
PC_TURN = true;
}
public void HUMAN_updateRight(){
HUMAN_SUM+=RandArr[CurrentSize-1];
jTextField5.setText(Integer.toString(HUMAN_SUM));
jTextField1.setText(Arrays.toString(RandArr));
CurrentSize--;
int [] NewRand = new int[CurrentSize];
for(int i = CurrentSize-1 ; i>=0;i--){
NewRand[i] = RandArr[i];
}
RandArr = NewRand;
jTextField2.setText(Arrays.toString(RandArr));
PC_TURN = true;
}
public static boolean WhoIsBigger(int[] arr){
int even=0,odd=0;
for(int i=0;i<arr.length;i+=2){
if(i%2==0){
even+=arr[i];
odd+=arr[i+1];
}
else{
odd+=arr[i];
even+=arr[i+1];
}
}
return even>odd;
}
public void PC_updateLeft(){
PC_SUM+=RandArr[0];
jTextField4.setText(Integer.toString(PC_SUM));
jTextField1.setText(Arrays.toString(RandArr));
CurrentSize--;
int [] NewRand = new int[CurrentSize];
for(int i = 1 ; i<=CurrentSize;i++){
NewRand[i-1] = RandArr[i];
}
RandArr = NewRand;
jTextField2.setText(Arrays.toString(RandArr));
}
public void PC_updateRight(){
PC_SUM+=RandArr[CurrentSize-1];
jTextField4.setText(Integer.toString(PC_SUM));
jTextField1.setText(Arrays.toString(RandArr));
CurrentSize--;
int [] NewRand = new int[CurrentSize];
for(int i = CurrentSize-1 ; i>=0;i--){
NewRand[i] = RandArr[i];
}
RandArr = NewRand;
jTextField2.setText(Arrays.toString(RandArr));
}
public void PC_TURN(){
if(WhoIsBigger(RandArr))
PC_updateLeft();
PC_updateRight();
}
public void FullGame(){
while(RandArr.length>0){
if(PC_TURN){
PC_TURN();
PC_TURN = false;
}
}
}
//start button listener
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) {
init();
jTextField2.setText(Arrays.toString(RandArr));
jTextField1.setText("-");
jButton1.setEnabled(false);
FullGame();
}
//left button listener
private void jButton2ActionPerformed(java.awt.event.ActionEvent evt) {
HUMAN_updateLeft();
}
//right button listener
private void jButton3ActionPerformed(java.awt.event.ActionEvent evt) {
HUMAN_updateRight();
}
How can i know that the real player has made his move so it'll change PC_TURN to True and the game will move on?

Firstly, you should follow Java Naming Conventions when it comes to naming your variables. As it stands, PC_TURN looks as though it is a constant, although it is not a constant since you are changing it's value. So a more appropriate name would be pcTurn.
You also seem to have a method called PC_TURN() which I am assuming is the method which causes the computer to take it's turn and do something. So it would be better if this was named something descriptive like takePCTurn(). Notice the use of camelCase throughout. Capital letters at the start of a name should be reserved for classes and interfaces, not variables or methods.
The same goes for your method name
public void FullGame()
should be written as
public void fullGame()
Keeping to coding conventions like this make it easier for others to read and understand your code and keep everything neat and tidy. It's a good habit to get into. :)
I don't know where your left and right buttons are being declared or what you have named them, but you will need to add an event listener to each button which causes something to happen when they are clicked. I also am unsure about the purpose of RandArr.length > 0. You really don't need a loop here since this is an application with a GUI, it is never going to close unless you explicitly tell it to (e.g by clicking the close button). So I will just give you a generic solution.
You basically want the players turn to trigger the computer to take it's turn until some game over condition is met.
Example:
//Assuming this is called when the Start button is clicked
public void fullGame() {
takePCTurn();
}
public void takePCTurn() {
//Do PC's turn logic
//You might want to check if the Computer Won the game here
}
class PlayerTurnListener implements ActionListener() {
public void actionPerformed(ActionEvent e) {
//Do Player's turn logic
//You might want to check if the Player Won the game here
takePCTurn();
}
}
//We can create an instance of our listener and add it to both buttons
PlayerTurnListener playerTurnListener = new PlayerTurnListener();
leftButton.addActionListener(playerTurnListener);
rightButton.addActionListener(playerTurnListener);
So the first thing that happens is fullGame() is called by your Start button which then calls takePCTurn(); causing the computer to take it's turn. Now nothing will happen until the player clicks the left or right button. When they do this, the PlayerTurnListener's actionPerformed() method is called and you can do some logic in there and then takePCTurn(); will be called once again.
Rinse and repeat until gameover.
Hope that helps :)

You should attach a clickListener onto the left and right buttons. Then when the user clicks one that event will be fired. You should change PC_TURN to true there and re-run the loop if needed.
Example:
JButton yourButton = new JButton("Your Button");
yourButton.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
PC_TURN = true;
// extra code
}
});

If this is a Swing or other GUI then you will need to get rid of the while loop.
Remember that GUI programs are non-linear and are event-driven, and so rather than a restricting while loop which risks completely feezing your GUI, you would change the program's state depending on whose turn it is -- have a variable indicating whose turn it is -- and then change the behavior of the program based on the state.
If you need more specific help, then you're going to need to ask a much more complete question including one with enough code and explanation to allow us to understand your problem better (but not too much code).
Regarding the code you've posted:
Yes, definitely get rid of that while loop.
Your code is hard to understand, mainly because you're variable naming is poor. Rather than using variable names like jTextField1, use names that make logical sense, that make your code "self-debuggin", such as humanScoreField and computerScoreField, etc.
Also learn and follow standard Java naming practices including having all variables start with lower case letters, classes with upper case letters, use camelCase for all except for constants which are all upper-case.
Tell more about just what this code is supposed to be doing, what the buttons and the JTextfields represent, what behaviors you desire, etc...

How does one prevent a JList from selecting elements when dragging beyond the end of its list?

A very similar question has been asked here, and while I acknowledge it, the question's solution doesn't quite solve my question. A JList, when clicked on, will select the index list item closest to the mouse click. A JList will also do this for every click+drag event fire.
I would like to prevent my JList from selecting items during click+drag events when the click+drag location is outside the visible list. How would I go about this?
I had considered overriding a different method, one involved in the click+drag events of selecting list items. I thought to try the setSelectionInterval() method.
JList<String list = new JList<String>(){
private static final long serialVersionUID = 1L;
#Override
public int locationToIndex(Point location) {
int index = super.locationToIndex(location);
if (index != -1 && !getCellBounds(index, index).contains(location)) {
clearSelection();
return -1;
//an excellent click-only solution to prohibit the selecting of
//items from beyond the visible list
}
else {
return index;
}
}
#Override
public void setSelectionInterval(int anchor, int lead) {
super.setSelectionInterval(anchor, lead);
System.out.println("setSelectionInterval");
}
};
I found that each time I click+drag anywhere on the displayed JList, I get the System.out message of "setSelectionInterval" that I added to the method above. I don't know where to go from here in terms of overriding methods. Maybe that is not how I should approach this. In the source code for setSelectionInterval() I got lost trying to find my way through to a whatever listener is involved, so I came here. :p
I'd greatly appreciate any pointers to where I should be looking or a solution altogether. Thanks in advance!
This is an SSCCE example that is close to how I am set up. As it is, the list will not select an item when a click-only event is fired away from the list items themselves. I would like this same effect to happen when click+drag events are fired away from the list items.
import java.awt.BorderLayout;
import java.awt.Point;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JPanel;
public class TestMain {
public static void main(String[] args) {
JFrame frame = new JFrame();
JPanel content = new JPanel(new BorderLayout());
String[] data = {"Luke", "Jeff", "Bryce"};
JList<String> list = new JList<String>(data){
private static final long serialVersionUID = 1L;
#Override
public int locationToIndex(Point location) {
System.out.println("location to index");
int index = super.locationToIndex(location);
if (index != -1 && !getCellBounds(index, index).contains(location)) {
clearSelection();
return -1;
}
else {
return index;
}
}
}
content.add(list, BorderLayout.CENTER);
frame.setContentPane(content);
frame.setSize(200,200);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}

If disabling the whole dragging feature is acceptable, then the following should help:
#Override
protected void processMouseMotionEvent(MouseEvent e) {
if(MouseEvent.MOUSE_DRAGGED != e.getID()) {
super.processMouseMotionEvent(e);
}
}

I would like to prevent my JList from selecting items during click+drag events when the click+drag location is outside the visible list.
Not sure I understand the requirement. Lets start with the first row being selected.
If you click on the first row and then continue to drag to the second the 2nd row gets highlighted. Continue dragging and the 3rd row gets highlighted. Continue dragging past the 3rd row and what do you want to happen?
Are you saying that you want the first row to be selected because that is where you started? If this is what you are asking, then you would need to look at the BasicListUI. This is where the mouse listeners are added to the JList. You would somehow need to handle the mousePressed event to save the currently selected row. You would then somehow need to override the default behaviour of the mouseDragged code to reset the selected row when you start to drag outside the last row.
I have no idea how to do all this.
I get the System.out message of "setSelectionInterval" that I added to the method above
Trying to override the code in that method is too late. The selection will continue to be updated as you drag the mouse. You don't know if this method is being called because the mouse is really on the last row or past the last row because you don't have access to the mouse point.
I suppose you could try to use the MouseInfo class to determine where the mouse is when this method is invoked, but then somehow you will still need to know that dragging originally started when the first row was selected. I have no idea how to do this either.

How to tell which item fired a mouse listener

HI all,
I'm trying to write a simple star rating component. I'm fairly new to the Java language and I'm not sure if what i want to accomplish can even be done in Java. Is it possible for me to add a JLabel inside an array of JLabel, and each JLabel in the array will have a mouse event listener. Now is it possible to set it up so that when the mouse event fires on say Label[3] that i can get the index value of it?
Here is how I built my Panel
public Rating(Integer max,int size) {
JLabel position = new JLabel[max];
this.setLayout(new FlowLayout());
for(int i=0; i != max;i++){
position[i]=new JLabel(icons.getIcon("star-empty", size));
position[i].setOpaque(true);
position[i].addMouseListener(this);
add(position[i]);
}
}
#Override
public void mouseEntered(MouseEvent e) {
JLabel a= (JLabel) e.getComponent();
//****Have some code in here to tell me where in the position array the event came from????***
int index = ?????
}
Thoughts/Idea/Suggestions please.
Note I thought of using buttons, but it looks messy and would love to find a way with ImageIcons.
THanks.

Instead of using the same listener for each label like you did:
position[i].addMouseListener(this);
...you can create a special listener class that takes the index number, and allows you to find it later:
position[i].addMouseListener(new RatingMouseListener(i));
Each label will have a separate instance of the listener with a different index value. The code for the inner class would look like something like this:
private class RatingMouseListener extends MouseAdapter {
private final int index;
public RatingMouseListener(int index) {
this.index = index;
}
#Override
public void mouseEntered(MouseEvent e) {
System.out.println("Mouse entered for rating " + index);
}
#Override
public void mouseExited(MouseEvent e) {
System.out.println("Mouse exited for rating " + index);
}
}
Then, you just override any method in MouseAdapter.
Also, like other people said, you might want to use JButtons instead of JLabels because they have better support for action events. You can still give them icons.

You could name each JLabel according to its index using its setName method, then use the MouseEvent's getComponent method to get the originating JLabel back, use getName on it and there's your index. That would be one way, but would involve storing the index information in two places (implicitly in its placement in the array, and explicitly as the label's name), so it's pretty much begging for inconsistency to arise.
You could also search through the array for the JLabel reference you get from getComponent, but that's not so great either, especially for large arrays.

The way I usually do it is:
int i;
for (i = 0; i <max; i++)
if (position[i] == e.getcomponent())
break;
now position[i] is the label you are looking for.

Just know that JButtons can look any way you'd like. They can have ImageIcons and don't even have to look like buttons.

Why is the index important? You know how to get the component, so just loop through the array to get the index.
Note I thought of using buttons, but it looks messy and would love to find a way with ImageIcons.
How does using a button solve the problem of determining the index? However, I also agree using a button is better than a label and then you would use an ActionListener instead of a MouseListener. You can make the button look like a label by using:
button.setBorderPainted( false );
Now if you use an ActionListener you can use the setActionCommand(...) method to store the index value of the button. Then in the event you use the getActionCommand(...) method.