We Keep Coding

Click Event - Accessing a boolean variable from another class [closed]

Closed. This question needs debugging details. It is not currently accepting answers.
Edit the question to include desired behavior, a specific problem or error, and the shortest code necessary to reproduce the problem. This will help others answer the question.
Closed 3 years ago.
Improve this question
Stuck on a problem that requires grabbing a boolean variable from another class.
I have the following for-loop, boolean and if-else statements
import java.awt.*;
import javax.swing.*;
import java.awt.Color.*;
import java.awt.event.MouseListener;
import java.awt.event.MouseEvent;
import java.util.Random;
public class Checkers extends JFrame
{
Random random = new Random();
private final int ROWS = 2;
private final int COLS = 5;
private final int GAP = 2;
private final int NUM = ROWS * COLS;
private int i;
private int score;
private JPanel pane = new JPanel(new GridLayout(ROWS,COLS, GAP,GAP));
private JPanel pane2 = new JPanel();
private JPanel pane3 = new JPanel();
private JButton btn1 = new JButton("Play A Game");
private JButton btn2 = new JButton("Exit");
private JButton btn3 = new JButton("Easy");
private JButton btn4 = new JButton("Intermediate");
private JButton btn5 = new JButton("Difficult");
private JLabel lbl1 = new JLabel ("score: " + score);
private JLabel gameLost = new JLabel("You lose! You got: " + score + " points");
private JButton btnRestart = new JButton("Restart");
private MyPanel [] panel = new MyPanel[NUM];
private Color col1 = Color.RED;
private Color col2 = Color.WHITE;
private Color col3 = Color.GREEN;
private Color tempColor;
private boolean isPanelDisabled;
//Starts the checkers GUI, calling the constructor below this.
public static void main(String[] args){
new Checkers();
}
//Sets the dimensions of the GUI, visibility, background color and
//contents via the setBoard();
public Checkers()
{
super("Checkers");
setSize(600,600);
setVisible(true);
setBackground(Color.BLACK);
setBoard();
}
//Makes the grid, contains a conditional boolean, adds the panels to grid based on i value.
//sets Colours accordingly
public void setBoard()
{
boolean isPanelDisabled = false;
for (int i = 0; i < panel.length; i++) {
panel[i] = new MyPanel(this);
pane.add(panel[i]);
if (i % COLS == 0) {
tempColor = col1;
}
if (i == 9 || i <8) {
panel[i].setBackground(col1);
}
if(i == 8){
isPanelDisabled = true;
panel[i].setBackground(col3);
}
}
//pane background colour and the size of this pane.
pane.setBackground(Color.BLACK);
pane.setPreferredSize(new Dimension(300,300));
//pane background colour and size of this pane.
pane2.setBackground(Color.white);
pane2.setPreferredSize(new Dimension(300,300));
//directions on the board where these panes appear.
add(pane, BorderLayout.WEST);
add(pane2, BorderLayout.EAST);
pane2.add(lbl1);
pane2.add(btnRestart);
btnRestart.addActionListener( e -> restartBoard());
pane2.setLayout(new BoxLayout(pane2, BoxLayout.PAGE_AXIS));
}
//increments the score for the user based on current points.
public void incrementScore(){
if (score != 5){
score++;
lbl1.setText("Score: " + Integer.toString(score));
}
else if(score == 5){
lbl1.setText("Congratulations!, you've won!, your score is:" + score);
}
}
}
and this mouseClicked Event
import java.awt.Color;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.*;
import java.awt.event.*;
import javax.swing.JPanel;
public class MyPanel extends JPanel implements MouseListener, ActionListener {
private final Checkers checkers;
private boolean isPanelDisabled;
//MyPanel Constructor that initiates a instance of checkers.
public MyPanel(Checkers checkers) {
this.checkers = checkers;
addMouseListener(this);
}
#Override
public void actionPerformed(ActionEvent e){
}
// Sets the panel colours according to their int number and the boolean condiiton.
#Override
public void mouseClicked(MouseEvent e) {
if (isPanelDisabled == true){
setBackground(Color.CYAN);
}
else{
setBackground(Color.BLACK);
checkers.incrementScore();
}
}
My Expected result of this should be that if the user clicks the 8th panel in that grid, then the color of that panel will be cyan when pressed and not black, but it cant access the boolean variable? where am i going wrong here?

Your question involves communication between objects of different classes, and there are several ways to do this, but most basic is to call a method of an object in one class to the other.
First lets set up the problem,... I've created classes called MyPanel2 and Checkers2, to distinguish them from yours.
Say in MyPanel2 we have a Checkers2 field and a boolean field called selected that is set to false:
private Checkers2 checkers;
private boolean selected = false;
along with appropriate boolean getter and setter:
public void setSelected(boolean selected) {
this.selected = selected;
}
public boolean isSelected() {
return selected;
}
And say within the Checkers2 class you have a 10 instances of MyPanel2 held within an array, and you want the user to be able to "select" instances of the class, but only allow 7 of them to be selected, and assume that you want to user the set up that you're currently using, you could give the main class, a method, public boolean isPanelDisabled(), and have the MyPanel2 class call this method to determine if selection is allowed. So within MyPanel2 you could have a MouseListener with something like:
#Override
public void mousePressed(MouseEvent e) {
if (selected) {
return;
}
// call the Checkers2 boolean method to check
if (checkers.isPanelDisabled()) {
setBackground(DISABLED_COLOR);
} else {
setBackground(SELECTED_COLOR);
setSelected(true);
}
}
Within Checkers2 .isPanelDisabled() method you'd iterate through the array of MyPanel2 instances to see how many have been selected, something like this could work:
public boolean isPanelDisabled() {
int count = 0;
for (MyPanel2 panel2 : myPanels) {
if (panel2.isSelected()) {
count++;
}
}
return count >= MAX_COUNT;
}
The whole MCVE testable code could look like:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class Checkers2 extends JFrame {
private static final int MAX_COUNT = 7;
private final int ROWS = 2;
private final int COLS = 5;
private final int GAP = 2;
private final int NUM = ROWS * COLS;
private MyPanel2[] myPanels = new MyPanel2[NUM];
public Checkers2() {
super("Checkers");
setDefaultCloseOperation(EXIT_ON_CLOSE);
JPanel gridPanel = new JPanel(new GridLayout(ROWS, COLS, 1, 1));
gridPanel.setBackground(Color.BLACK);
gridPanel.setBorder(BorderFactory.createLineBorder(Color.BLACK));
for (int i = 0; i < myPanels.length; i++) {
MyPanel2 myPanel = new MyPanel2(this);
gridPanel.add(myPanel);
myPanels[i] = myPanel;
}
JButton resetButton = new JButton("Reset");
resetButton.setMnemonic(KeyEvent.VK_R);
resetButton.addActionListener(evt -> {
for (MyPanel2 myPanel2 : myPanels) {
myPanel2.reset();
}
});
JButton exitButton = new JButton("Exit");
exitButton.setMnemonic(KeyEvent.VK_X);
exitButton.addActionListener(evt -> System.exit(0));
JPanel buttonPanel = new JPanel();
buttonPanel.add(resetButton);
add(gridPanel);
add(buttonPanel, BorderLayout.PAGE_END);
pack();
setLocationRelativeTo(null);
}
public boolean isPanelDisabled() {
int count = 0;
for (MyPanel2 panel2 : myPanels) {
if (panel2.isSelected()) {
count++;
}
}
return count >= MAX_COUNT;
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
new Checkers2().setVisible(true);
});
}
}
class MyPanel2 extends JPanel {
private static final int PREF_W = 200;
private static final int PREF_H = PREF_W;
private static final int GR = 240;
public static final Color BASE_COLOR = new Color(GR, GR, GR);
public static final Color DISABLED_COLOR = Color.CYAN;
public static final Color SELECTED_COLOR = Color.BLACK;
private Checkers2 checkers;
private boolean selected = false;
public MyPanel2(Checkers2 checkers) {
setBackground(BASE_COLOR);
this.checkers = checkers;
setPreferredSize(new Dimension(PREF_W, PREF_H));
addMouseListener(new MyMouse());
}
public void setSelected(boolean selected) {
this.selected = selected;
}
public boolean isSelected() {
return selected;
}
public void reset() {
setBackground(BASE_COLOR);
setSelected(false);
}
private class MyMouse extends MouseAdapter {
#Override
public void mousePressed(MouseEvent e) {
if (selected) {
return;
}
if (checkers.isPanelDisabled()) {
setBackground(DISABLED_COLOR);
} else {
setBackground(SELECTED_COLOR);
setSelected(true);
}
}
}
}
Another Option is to take all the logic out of MyPanel and put it into the main program, something like:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
#SuppressWarnings("serial")
public class Checkers3 extends JPanel {
private static final int MAX_COUNT = 7;
private final int ROWS = 2;
private final int COLS = 5;
private final int GAP = 2;
private final int NUM = ROWS * COLS;
private MyPanel3[] myPanels = new MyPanel3[NUM];
public Checkers3() {
JPanel gridPanel = new JPanel(new GridLayout(ROWS, COLS, 1, 1));
gridPanel.setBackground(Color.BLACK);
gridPanel.setBorder(BorderFactory.createLineBorder(Color.BLACK));
MyMouse myMouse = new MyMouse();
for (int i = 0; i < myPanels.length; i++) {
MyPanel3 myPanel = new MyPanel3();
myPanel.addMouseListener(myMouse);
gridPanel.add(myPanel);
myPanels[i] = myPanel;
}
JButton resetButton = new JButton("Reset");
resetButton.setMnemonic(KeyEvent.VK_R);
resetButton.addActionListener(evt -> {
for (MyPanel3 myPanel : myPanels) {
myPanel.reset();
}
});
JButton exitButton = new JButton("Exit");
exitButton.setMnemonic(KeyEvent.VK_X);
exitButton.addActionListener(evt -> System.exit(0));
JPanel buttonPanel = new JPanel();
buttonPanel.add(resetButton);
setLayout(new BorderLayout());
add(gridPanel);
add(buttonPanel, BorderLayout.PAGE_END);
}
public boolean isPanelDisabled() {
int count = 0;
for (MyPanel3 panel : myPanels) {
if (panel.isSelected()) {
count++;
}
}
return count >= MAX_COUNT;
}
private class MyMouse extends MouseAdapter {
#Override
public void mousePressed(MouseEvent e) {
MyPanel3 myPanel = (MyPanel3) e.getSource();
if (myPanel.isSelected()) {
return; // it's already selected
} else if (isPanelDisabled()) {
myPanel.setSelected(false);
} else {
myPanel.setSelected(true);
}
}
}
private static void createAndShowGui() {
Checkers3 mainPanel = new Checkers3();
JFrame frame = new JFrame("Checkers");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
}
#SuppressWarnings("serial")
class MyPanel3 extends JPanel {
private static final int PREF_W = 200;
private static final int PREF_H = PREF_W;
private static final int GR = 240;
public static final Color BASE_COLOR = new Color(GR, GR, GR);
public static final Color DISABLED_COLOR = Color.CYAN;
public static final Color SELECTED_COLOR = Color.BLACK;
private boolean selected = false;
public MyPanel3() {
setBackground(BASE_COLOR);
setPreferredSize(new Dimension(PREF_W, PREF_H));
}
public void setSelected(boolean selected) {
this.selected = selected;
Color background = selected ? SELECTED_COLOR : DISABLED_COLOR;
setBackground(background);
}
public boolean isSelected() {
return selected;
}
public void reset() {
setSelected(false);
setBackground(BASE_COLOR);
}
}
But the BEST option is to put all logic within a separate model class (or classes) and make the GUI's as dumb as possible.

Remove Specific Component from JPanel - Java

I currently have multiples of a JPanel (ItemPanel) within a JPanel (FlipPanel) within my JFrame. An ItemPanel is added to FlipPanel when a JButton in a separate panel (FlipFormPanel) is pressed. I have a JButton on ItemPanel labelled "Cancel" and I would like to remove the specific ItemPanel whose Cancel JButton was pressed. What I currently have only removes the ItemPanel whose button was selected, but after that no other buttons will remove any more ItemPanels.
How can I fix my code to do what I'm trying to accomplish?
My code for each class is below. I tried to remove as much of the extraneous material as possible to avoid cluttering the task at hand. I believe the issue is located in FlipPanel under the methods addItemPanel(, setItemListener(, and in the ItemPanelListener and ItemPanelEvent classes. Thanks for any help provided.
FlipPanel:
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Font;
import java.awt.GridBagLayout;
import java.util.ArrayList;
import java.util.List;
import javax.swing.BorderFactory;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import net.miginfocom.swing.MigLayout;
public class FlipPanel extends JPanel {
private JPanel mainPanel;
private JScrollPane scrollPane;
private ItemPanel itemPanel;
private JPanel titlePanel;
private JLabel titleLabel;
private List<ItemPanel> itmPnls = new ArrayList<ItemPanel>();
private int count;
public FlipPanel() {
setLayout(new BorderLayout());
mainPanel = new JPanel();
scrollPane = new JScrollPane(mainPanel);
add(scrollPane, BorderLayout.CENTER);
mainPanel.setLayout(new MigLayout("align center, fillx", "fill", ""));
titlePanel = new JPanel();
mainPanel.add(titlePanel, "wrap, gapbottom 13, gaptop 7");
titlePanel.setLayout(new GridBagLayout());
titleLabel = new JLabel("CURRENT FLIPS");
Font labelFont = titleLabel.getFont();
titleLabel.setFont(new Font(labelFont.getName(), Font.BOLD, 25));
titlePanel.setBorder(BorderFactory.createMatteBorder(0, 0, 3, 0, Color.BLACK));
titlePanel.add(titleLabel);
count = 0;
}
public void addItemPanel(String item, String buyPrice, String sellPrice,
String quantity, String pcBuyPrice, String pcSellPrice) {
this.itemPanel = new ItemPanel(count, item, buyPrice, sellPrice, quantity,
pcBuyPrice, pcSellPrice);
mainPanel.add(itemPanel, "wrap");
itmPnls.add(itemPanel);
count++;
setItemListener(this.itemPanel);
}
public void setItemListener(ItemPanel iP) {
iP.setItemPanelListener(new ItemPanelListener() {
public void itemPanelEventOccurred(ItemPanelEvent e) {;
System.out.println("Remove");
System.out.println("Current Position: " + e.getPosition());
mainPanel.remove(itmPnls.get(e.getPosition()));
System.out.println("Positions:");
for (int i = 0; i < count; i++) {
System.out.println(itmPnls.get(i).getPosition());
}
if(e.getPosition() < count - 1) {
for (int i = e.getPosition() + 1; i < count; i++) {
itmPnls.get(i).setPosition(i);
}
}
count--;
revalidate();
repaint();
System.out.println("Positions:");
for (int i = 0; i < count; i++) {
System.out.println(itmPnls.get(i).getPosition());
}
setItemListener(itmPnls.get(0));
}
});
}
ItemPanel:
import javax.swing.JPanel;
public class ItemPanel extends JPanel {
private int position;
private String item;
private String buyPrice;
private String sellPrice;
private String quantity;
private String pcBuyPrice;
private String pcSellPrice;
private JButton logBtn;
private JButton editBtn;
private JButton cancelBtn;
private ItemPanelListener itemPanelListener;
public ItemPanel(int position, String item, String buyPrice, String sellPrice,
String quantity, String pcBuyPrice, String pcSellPrice) {
this.position = position;
this.item = item;
this.buyPrice = buyPrice;
this.sellPrice = sellPrice;
this.quantity = quantity;
this.pcBuyPrice = pcBuyPrice;
this.pcSellPrice = pcSellPrice;
Dimension dim = getPreferredSize();
dim.height = 100;
setPreferredSize(dim);
setBorder(BorderFactory.createLineBorder(Color.DARK_GRAY));
logBtn = new JButton("Log Item");
editBtn = new JButton("Edit Item");
cancelBtn = new JButton("Cancel Item");
setupLabels();
setupCancelItemButton();
layoutComponents();
}
public int getPosition() {
return position;
}
public void setPosition(int pos) {
position = pos;
}
public void setupCancelItemButton() {
cancelBtn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
ItemPanelEvent ev = new ItemPanelEvent(this);
if (itemPanelListener != null) {
itemPanelListener.itemPanelEventOccurred(ev);
}
}
});
}
public void setItemPanelListener(ItemPanelListener listener) {
this.itemPanelListener = listener;
}
ItemPanelListener:
import java.util.EventListener;
public interface ItemPanelListener extends EventListener {
public void itemPanelEventOccurred(ItemPanelEvent e);
}
ItemPanelEvent:
import java.util.EventObject;
public class ItemPanelEvent extends EventObject {
private int position;
public ItemPanelEvent(Object source) {
super(source);
}
public ItemPanelEvent(Object source, int position) {
super(source);
this.position = position;
}
public int getPosition() {
return position;
}
}

jbutton does not work

Hi I have the following code where I have a start and stop button . when start is pressed canvas starts painting but I cannot press stop button until the start operation is done . I need to stop and resume the paint on the button press . Once the start button is pressed the other buttons cannot be pressed till the canvas is painted.
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.GridLayout;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.Hashtable;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
import javax.swing.Timer;
public abstract class JUIApp extends JPanel implements ActionListener {
public static CACanvas cacanvas= null;
public ArrayList<int[]> genL;
public JFrame frame = null;
protected JPanel mainPanel = null;
private JButton btn0 = null;
private JButton btn1 = null;
private JButton btn2 = null;
#SuppressWarnings("rawtypes")
DefaultComboBoxModel rules = null;
#SuppressWarnings("rawtypes")
JComboBox rulesCombo =null;
JScrollPane ruleListScrollPane=null;
JLabel lable=null;
JTextField generation=null;
JLabel gLable=null;
public static String Rule;
public static String Generations;
public boolean isChanged =false;
public int gridCellSize=4;
private static final long serialVersionUID = 1L;
public int genCurrent=0;
public int posCurrent=0;
public int i;
public Color cellColor= null;
public Timer waitTimer;
public static boolean waitFlag;
public static boolean alert1Flag=false;
public boolean stopFlag=false;
public JLabel Alert1=new JLabel();
public int genCheck=0;
//private List<Point> fillCells;
public JUIApp() {
initGUI();
}
public void initGUI() {
//fillCells = new ArrayList<>(25);
frame = new JFrame();
frame.setTitle("Cellular Automata Demo");
frame.setSize(1050, 610);
frame.setResizable(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(getMainPanel(),BorderLayout.NORTH);
frame.setVisible(true);
Toolkit.getDefaultToolkit().setDynamicLayout(false);
cacanvas=new CACanvas();
frame.add(cacanvas);
}
#SuppressWarnings({ "unchecked", "rawtypes" })
public JPanel getMainPanel() {
mainPanel = new JPanel();
mainPanel.setLayout(new FlowLayout());
//cacanvas=new CACanvas();
btn0 = new JButton("Start");
btn0.addActionListener(this);
//waitTimer = new Timer(1000, this);
mainPanel.add(btn0);
JButton btn2 = new JButton("Stop");
btn2.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent s)
{
stopFlag=true;
//cacanvas.repaint();
}
});
mainPanel.add(btn2);
btn1 = new JButton("Clear");
btn1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e)
{
CACanvas.clearFlag=true;
generation.setText("");
alert1Flag=true;
rulesCombo.setSelectedIndex(0);
Alert1.setText("Please enter the number of generations");
Alert1.setBounds(30, 20, 5, 5);
Alert1.setVisible(alert1Flag);
mainPanel.add(Alert1);
cacanvas.repaint();
frame.setSize(1060, 610);
}
});
mainPanel.add(btn1);
lable=new JLabel();
lable.setText("Select Rule :");
mainPanel.add(lable);
rules=new DefaultComboBoxModel();
for (int i=0;i<=100;i++)
{
String p=String.valueOf(i);
rules.addElement(p);
}
rules.addElement("250");
rules.addElement("254");
rulesCombo = new JComboBox(rules);
rulesCombo.setSelectedIndex(0);
ruleListScrollPane = new JScrollPane(rulesCombo);
mainPanel.add(ruleListScrollPane);
//mainPanel.revalidate();
gLable=new JLabel();
gLable.setText("Enter the number of Generations (Max 64)");
generation=new JTextField(2);
mainPanel.add(gLable);
mainPanel.add(generation);
// mainPanel.add(cacanvas);
return mainPanel;
}
public abstract void run();
#Override
public void actionPerformed(ActionEvent arg0) {
Alert1.setVisible(false);
waitFlag=false;
System.out.println("We received an ActionEvent " + arg0);
Generations=generation.getText();
System.out.println(Generations);
Rule = "";
if (rulesCombo.getSelectedIndex() != -1) {
Rule =
(String) rulesCombo.getItemAt
(rulesCombo.getSelectedIndex());
}
System.out.println(Rule);
int rule=Integer.parseInt(Rule);
Hashtable<String,Integer> rules= new Hashtable<String,Integer>();
CARule ruleClass=new CARule();
rules=ruleClass.setRule(rule);
CAGenetationSet sa =new CAGenetationSet(100, false,rules);
genL=new ArrayList<int[]>();
genL=sa.runSteps(Integer.parseInt(Generations));
System.out.println("calling pattern set");
for(int i=0;i<=genL.size()-1;i++)
{
System.out.println("Painting generation :"+i);
if(stopFlag==false)
{
cacanvas.repaint();
}
//genPaint();
//sleep();
int[] newCell=genL.get(i);
for(int r=0;r<newCell.length;r++)
{
if(newCell[r]==1)
{
System.out.println("Generaton is"+i+"CellLife is"+r);
cacanvas.fillCell(i,r);
}
}
}
/*cacanvas.patternSet(genL);
waitFlag=true;
System.out.println("run completed");
// cacanvas.clearFlag=true;
*/
}
public void genPaint()
{
cacanvas.repaint();
}
public void sleep()
{
try
{
Thread.sleep(100);
}
catch (InterruptedException e)
{
e.printStackTrace();
}
}
public static void main(String[] args) {
JUIApp app = new JUIApp() {
#Override
public void run() {
// TODO Auto-generated method stub
System.out.println("Run method");
}
};
}
}

Seems like you are using the current Thread on that task, you should create another Thread and add one listeners code to the new Thread.

I get a stack overflow error

I'm trying to create a program where you press start and a new JFrame comes up with 3 buttons , you have to switch the button after you click on it using a random , I'm fairly new to java so I don't know what to do. Thank you
package code;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.Timer;
public class StartListener implements java.awt.event.ActionListener {
private int counter;
private Game Ga;
private JFrame z;
private int x;
public StartListener(Game a, int co){
Ga=a;
counter = co;
}
public void actionPerformed(ActionEvent e) {
Timer time = new Timer(10000,new Time(Ga));
time.start();
z = new JFrame("Sequence game");
FlowLayout fl = new FlowLayout(0, 50, 40);
z.getContentPane().setLayout(fl);
z.setVisible(true);
JButton a = new JButton("A");
Font f = a.getFont();
Font myFont = f.deriveFont(Font.BOLD, f.getSize()*4);
a.setSize(200,100);
a.setVisible(true);
JButton b = new JButton("B");
b.setVisible(true);
b.setSize(200,100);
JButton c = new JButton("C");
c.setVisible(true);
c.setSize(200,100);
z.getContentPane().add(a);
z.getContentPane().add(b);
z.getContentPane().add(c);
z.pack();
Random r = new Random();
x=r.nextInt(3);
figure(a,b,c,x,myFont,f);}
public void figure(JButton a,JButton b, JButton c, int x, Font myFont,Font f){
if(x==0){
a.setEnabled(true);
b.setEnabled(false);
c.setEnabled(false);
a.setFont(myFont);
b.setFont(f);
c.setFont(f);
x =buttonA(a);
figure(a,b,c,x,myFont,f);
;}
else if(x==1){
a.setEnabled(false);
b.setEnabled(true);
c.setEnabled(false);
a.setFont(f);
c.setFont(f);
b.setFont(myFont);
x = buttonB(b);
figure(a,b,c,x,myFont,f);
}
else if(x==2){
a.setEnabled(false);
b.setEnabled(false);
c.setEnabled(true);
a.setFont(f);
b.setFont(f);
c.setFont(myFont);
x = buttonC(c);
figure(a,b,c,x,myFont,f);
}
}
public int buttonA(JButton a){
Random r = new Random();
int rand = 0;
a.addActionListener(new Something(Ga));
rand = r.nextInt(3);
return rand;
}
public int buttonB(JButton b){
Random r = new Random();
int rand = 0;
b.addActionListener(new Something(Ga));
rand=r.nextInt(3);
return rand;
}
public int buttonC(JButton c){
Random r = new Random();
int rand=0;
c.addActionListener(new Something(Ga));
rand = r.nextInt(3);
return rand;
}
}
And here's the code for Something
package code;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class Something implements ActionListener {
private Game G;
public Something(Game a){
G = a;
}
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
G.increment();
}
}
Here's the error :
Exception in thread "AWT-EventQueue-0" java.lang.StackOverflowError
at java.awt.Component.enable(Unknown Source)
at java.awt.Component.setEnabled(Unknown Source)
at javax.swing.JComponent.setEnabled(Unknown Source)
at javax.swing.AbstractButton.setEnabled(Unknown Source)

Your figure method continuously calls itself recursively forever, or until stack space runs out. Solution: get rid of those recursive calls. Also you really don't want to keep adding multiple ActionListeners on to JButtons, all this suggesting that you will want to refactor and perhaps redesign the entire program.
You will want to change the state of a field in the class, and use that field's state to decide what to do within the ActionListener.
For example:
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.*;
#SuppressWarnings("serial")
public class SwapButtons extends JPanel {
private static final Font ACTIVE_FONT = new Font(Font.DIALOG, Font.BOLD, 15);
private static final String[] BTN_TEXT = { "Monday", "Tuesday", "Wednesday" };
private static final int EXTRA_WIDTH = 50;
private List<AbstractButton> buttonList = new ArrayList<>();
private int buttonIndex = 0;
public SwapButtons() {
setLayout(new GridLayout(1, 0, 5, 0));
BtnListener btnListener = new BtnListener();
for (int i = 0; i < BTN_TEXT.length; i++) {
JButton button = new JButton(BTN_TEXT[i]);
button.addActionListener(btnListener);
buttonList.add(button); // add to ArrayList
add(button); // add to GUI
}
setActiveButton();
setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
}
#Override
public Dimension getPreferredSize() {
Dimension superSz = super.getPreferredSize();
if (isPreferredSizeSet()) {
return superSz;
}
// give preferred size extra width so gui can handle larger fonts
int prefW = superSz.width + EXTRA_WIDTH;
int prefH = superSz.height;
return new Dimension(prefW, prefH);
}
private void setActiveButton() {
// iterate through buttonList, turning on the "active" button
// as determined by the buttonIndex variable
for (int i = 0; i < buttonList.size(); i++) {
if (i == buttonIndex) {
buttonList.get(i).setFont(ACTIVE_FONT);
buttonList.get(i).setEnabled(true);
} else {
buttonList.get(i).setFont(null);
buttonList.get(i).setEnabled(false);
}
}
}
private class BtnListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
// show which button pressed
System.out.println("Button Pressed: " + e.getActionCommand());
// advance button index so that next button can be activated
buttonIndex++;
// but change index to 0 if buttonList size is reached
buttonIndex %= buttonList.size();
// activate the next button:
setActiveButton();
}
}
private static void createAndShowGui() {
SwapButtons mainPanel = new SwapButtons();
JFrame frame = new JFrame("Swap Buttons");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(mainPanel);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}

combo getSelectedItem but then

Simple question for you , i input this code and i see the combobox and the label, but after the selection of the combo the label should be with an image. This does not happen ... Surely i forgot something
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ChooseFrame extends JFrame
{
public ChooseFrame()
{
labelLeagueImage = new JLabel("Liga");
comboLeague = createComboLeague();
class ChooseListener implements ActionListener
{
public void actionPerformed(ActionEvent event)
{
String league = (String)comboLeague.getSelectedItem();
if (league.equals("Italia - Serie A"))
{
ImageIcon icon = new ImageIcon("Italia - Serie A.png");
labelLeagueImage.setIcon(icon);
}
}
}
listener = new ChooseListener();
leaguePanel = new JPanel();
leaguePanel.add(comboLeague);
leaguePanel.add(labelLeagueImage);
add(leaguePanel);
setSize(FRAME_WIDTH, FRAME_HEIGHT);
}
public JComboBox createComboLeague()
{
JComboBox combo = new JComboBox();
combo.addItem("Select a league");
combo.addItem("Italia - Serie A");
combo.addItem("Italia - Serie B");
combo.addActionListener(listener);
return combo;
}
private JPanel leaguePanel;
private JComboBox comboLeague;
private JLabel labelLeagueImage;
private ActionListener listener;
private static final int FRAME_WIDTH = 300;
private static final int FRAME_HEIGHT = 600;
}

At the time you create the combo box and assign the listener, in createComboLeague(), the listener is still null. It's initialized only after the createComboLeague() method has been called.

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ChooseFrame extends JFrame
{
private JPanel leaguePanel;
private JComboBox comboLeague;
private JLabel labelLeagueImage;
private ActionListener listener;
private static final int FRAME_WIDTH = 300;
private static final int FRAME_HEIGHT = 600;
public ChooseFrame()
{
labelLeagueImage = new JLabel("Liga");
comboLeague = createComboLeague();
// listener = new ChooseListener();
leaguePanel = new JPanel();
leaguePanel.add(comboLeague);
leaguePanel.add(labelLeagueImage);
add(leaguePanel);
setSize(FRAME_WIDTH, FRAME_HEIGHT);
}
public JComboBox createComboLeague()
{
JComboBox combo = new JComboBox();
combo.addItem("Select a league");
combo.addItem("Italia - Serie A");
combo.addItem("Italia - Serie B");
combo.addActionListener(listener);
combo.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent event) {
// TODO Auto-generated method stub
String league = (String)comboLeague.getSelectedItem();
if (league.equals("Italia - Serie A"))
{
ImageIcon icon = new ImageIcon("Italia - Serie A.png");
labelLeagueImage.setIcon(icon);
}
}
});
return combo;
}
public static void main(String[] args) {
ChooseFrame cs=new ChooseFrame();
cs.setVisible(true);
}
}