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Can I use actionListeners on JPanels?

I am trying to add and actionListener to a JPanel it's self but keep getting the error"cannot find symbol". I was just wondering if it is possible to do this as I want to be able to click on the panel and make the colour change. Any help would be appreciated.
Here is what i have so far.
import java.awt.*;
import javax.swing.*;
import javax.swing.JPanel.*;
import java.awt.Color.*;
import java.awt.event.*;
/**
* Write a description of class SimpleFrame here.
*
* #author OFJ2
* #version
*/
public class Game extends JFrame
implements ActionListener
{
private final int ROWS = 5;
private final int COLUMS = 2;
private final int GAP = 2;
private final int SIZE = ROWS * COLUMS;
private int x;
private JPanel leftPanel = new JPanel(new GridLayout(ROWS,COLUMS, GAP,GAP));
private JPanel [] gridPanel = new JPanel[SIZE];
private JPanel middlePanel = new JPanel();
private JPanel rightPanel = new JPanel();
private Color col1 = Color.GREEN;
private Color col2 = Color.YELLOW;
private Color tempColor;
public Game()
{
super("Chasing Bombs OFJ2");
setSize(200,200);
setVisible(true);
makeFrame();
}
public void makeFrame()
{
Container contentPane = getContentPane();
contentPane.setLayout(new GridLayout());
leftPanel.setLayout(new GridLayout(ROWS, COLUMS));
//JLabel label2 = new JLabel("Pocahontas");
JButton playButton = new JButton("Play Game");
JButton exitButton = new JButton("Exit");
JButton easyButton = new JButton("Easy");
JButton mediumButton = new JButton("Medium");
JButton hardButton = new JButton("Hard");
add(leftPanel);
add(middlePanel, new FlowLayout());
add(rightPanel);
setGrid();
middlePanel.add(playButton);
middlePanel.add(exitButton);
rightPanel.add(easyButton);
rightPanel.add(mediumButton);
rightPanel.add(hardButton);
leftPanel.setBackground(Color.PINK);
middlePanel.setBackground(Color.RED);
easyButton.addActionListener(this);
mediumButton.addActionListener(this);
hardButton.addActionListener(this);
playButton.addActionListener(this);
exitButton.addActionListener(this);
}
public void setGrid()
{
for(int x = 0; x < SIZE; x++) {
gridPanel[x] = new JPanel();
gridPanel[x].setBorder(BorderFactory.createLineBorder(Color.BLACK));
leftPanel.add(gridPanel[x]);
gridPanel[x].setBackground(Color.GREEN);
gridPanel[x].addActionListener(this);
}
}
#Override
public void actionPerformed(ActionEvent e)
{
Object source = e.getSource();
if (source == gridPanel[0]){
gridPanel[x].setBackground(Color.BLACK);
}
}
}
I have tried to find if there is any other method that is needed to do this but cant find anything. Is it possible that I will have to add a button to fill each of the panels to make this work?
Thanks!

It defaults to no addActionListener, and the code below is a reference suggestion.
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.ArrayList;
import java.util.List;
class GPanel extends JPanel {
private List<ActionListener> listenerList = new ArrayList<>();
public GPanel() {
addMouseListener(new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent e) {
var event = new ActionEvent(this, ActionEvent.ACTION_PERFORMED, "GPanel");
for (var i : listenerList) {
i.actionPerformed(event);
}
}
});
}
public void addActionListener(ActionListener listener) {
listenerList.add(listener);
}
}
public class ActionListenerTest extends JFrame {
public static void main(String[] args) {
new ActionListenerTest();
}
public ActionListenerTest() {
GPanel test = new GPanel();
test.setBackground(Color.BLUE);
add(test);
test.addActionListener(e-> {
System.out.println("Click: " + e.getActionCommand());
});
pack();
setDefaultCloseOperation(EXIT_ON_CLOSE);
setVisible(true);
}
}

Repainting a JPanel

I have two frames with contents . The first one has a jlabel and jbutton which when it is clicked it will open a new frame. I need to repaint the first frame or the panel that has the label by adding another jlabel to it when the second frame is closed.
//Edited
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class FirstFrame extends JPanel implements KeyListener{
private static String command[];
private static JButton ok;
private static int count = 1;
private static JTextField text;
private static JLabel labels[];
private static JPanel p ;
private static JFrame frame;
public int getCount(){
return count;
}
public static void createWindow(){
JFrame createFrame = new JFrame();
JPanel panel = new JPanel(new GridLayout(2,1));
text = new JTextField (30);
ok = new JButton ("Add");
ok.requestFocusInWindow();
ok.setFocusable(true);
panel.add(text);
panel.add(ok);
text.setFocusable(true);
text.addKeyListener(new FirstFrame());
createFrame.add(panel);
createFrame.setVisible(true);
createFrame.setSize(600,300);
createFrame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
createFrame.setLocationRelativeTo(null);
createFrame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent windowEvent) {
System.out.println(command[count]);
if(command[count] != null){
p.add(new JLabel("NEW LABEL"));
p.revalidate();
p.repaint();
count++;
System.out.println(count);
}
}
});
if(count >= command.length)
count = 1;
ok.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
if(command[count] == null)
command[count] = text.getText();
else
command[count] = command[count]+", "+text.getText();
text.setText("");
}
});
}
public FirstFrame(){
p = new JPanel();
JButton create = new JButton ("CREATE");
command = new String[2];
labels = new JLabel[2];
addKeyListener(this);
create.setPreferredSize(new Dimension(200,100));
//setLayout(new BorderLayout());
p.add(new JLabel("dsafsaf"));
p.add(create);
add(p);
//JPanel mainPanel = new JPanel();
/*mainPanel.setFocusable(false);
mainPanel.add(create);
*/
create.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
createWindow();
}
});
//add(mainPanel, BorderLayout.SOUTH);
}
public static void main(String[] args) {
frame = new JFrame();
frame.add(new FirstFrame());
frame.setVisible(true);
frame.pack();
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
}
#Override
public void keyReleased(KeyEvent e) {
}
#Override
public void keyTyped(KeyEvent e) {
}
#Override
public void keyPressed(KeyEvent e) {
if(e.getKeyCode() == KeyEvent.VK_ENTER)
if(ok.isDisplayable()){
ok.doClick();
return;}
}
}
}
});
}
}

As per my first comment, you're better off using a dialog of some type, and likely something as simple as a JOptionPane. For instance in the code below, I create a new JLabel with the text in a JTextField that's held by a JOptionPane, and then add it to the original GUI:
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import javax.swing.*;
#SuppressWarnings("serial")
public class FirstPanel2 extends JPanel {
private static final int PREF_W = 600;
private static final int PREF_H = 300;
private JTextField textField = new JTextField("Hovercraft rules!", 30);
private int count = 0;
public FirstPanel2() {
AddAction addAction = new AddAction();
textField.setAction(addAction);
add(textField);
add(new JButton(addAction));
}
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
private class AddAction extends AbstractAction {
public AddAction() {
super("Add");
}
#Override
public void actionPerformed(ActionEvent e) {
String text = textField.getText();
final JTextField someField = new JTextField(text, 10);
JPanel panel = new JPanel();
panel.add(someField);
int result = JOptionPane.showConfirmDialog(FirstPanel2.this, panel, "Add Label",
JOptionPane.OK_CANCEL_OPTION, JOptionPane.PLAIN_MESSAGE);
if (result == JOptionPane.OK_OPTION) {
JLabel label = new JLabel(someField.getText());
FirstPanel2.this.add(label);
FirstPanel2.this.revalidate();
FirstPanel2.this.repaint();
}
}
}
private static void createAndShowGui() {
FirstPanel2 mainPanel = new FirstPanel2();
JFrame frame = new JFrame("My Gui");
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();
}
});
}
}
Also, don't add KeyListeners to text components as that is a dangerous and unnecessary thing to do. Here you're much better off adding an ActionListener, or as in my code above, an Action, so that it will perform an action when the enter key is pressed.
Edit
You ask:
Just realized it is because of the KeyListener. Can you explain please the addAction ?
This is functionally similar to adding an ActionListener to a JTextField, so that when you press enter the actionPerformed(...) method will be called, exactly the same as if you pressed a JButton and activated its ActionListener or Action. An Action is like an "ActionListener" on steroids. It not only behaves as an ActionListener, but it can also give the button its text, its icon and other properties.

how to auto change image in java swing?

Hi i am creating a java desktop application where i want to show image and i want that all image should change in every 5 sec automatically i do not know how to do this
here is my code
public class ImageGallery extends JFrame
{
private ImageIcon myImage1 = new ImageIcon ("E:\\SOFTWARE\\TrainPIS\\res\\drawable\\yellow.png");
private ImageIcon myImage2 = new ImageIcon ("E:\\SOFTWARE\\TrainPIS\\res\\drawable\\d.jpg");
private ImageIcon myImage3 = new ImageIcon ("E:\\SOFTWARE\\TrainPIS\\res\\drawable\\e.jpg");
private ImageIcon myImage4 = new ImageIcon ("E:\\SOFTWARE\\TrainPIS\\res\\drawable\f.jpg");
JPanel ImageGallery = new JPanel();
private ImageIcon[] myImages = new ImageIcon[4];
private int curImageIndex=0;
public ImageGallery ()
{
ImageGallery.add(new JLabel (myImage1));
myImages[0]=myImage1;
myImages[1]=myImage2;
myImages[2]=myImage3;
myImages[3]=myImage4;
add(ImageGallery, BorderLayout.NORTH);
JButton PREVIOUS = new JButton ("Previous");
JButton NEXT = new JButton ("Next");
JPanel Menu = new JPanel();
Menu.setLayout(new GridLayout(1,4));
Menu.add(PREVIOUS);
Menu.add(NEXT);
add(Menu, BorderLayout.SOUTH);
}
How can i achieve this?
Thanks in advance

In this example, a List<JLabel> holds each image selected from a List<Icon>. At each step of a javax.swing.Timer, the list of images is shuffled, and each image is assigned to a label.
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import javax.swing.Icon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.UIManager;
/**
* #see http://stackoverflow.com/a/22423511/230513
* #see http://stackoverflow.com/a/12228640/230513
*/
public class ImageShuffle extends JPanel {
private List<Icon> list = new ArrayList<Icon>();
private List<JLabel> labels = new ArrayList<JLabel>();
private Timer timer = new Timer(1000, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
update();
}
});
public ImageShuffle() {
this.setLayout(new GridLayout(1, 0));
list.add(UIManager.getIcon("OptionPane.errorIcon"));
list.add(UIManager.getIcon("OptionPane.informationIcon"));
list.add(UIManager.getIcon("OptionPane.warningIcon"));
list.add(UIManager.getIcon("OptionPane.questionIcon"));
for (Icon icon : list) {
JLabel label = new JLabel(icon);
labels.add(label);
this.add(label);
}
timer.start();
}
private void update() {
Collections.shuffle(list);
int index = 0;
for (JLabel label : labels) {
label.setIcon(list.get(index++));
}
}
private void display() {
JFrame f = new JFrame("ImageShuffle");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.add(this);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
new ImageShuffle().display();
}
});
}
}

one way of achieving your goal is setting a swing.Timer to notify its action listeners every 5 seconds, set your class to be the listener for the timer and implement the actionListener interface by having an actionPerformed method which will change all images using their setImage method. the code should look like this:
public class ImageGallery extends JFrame implements ActionListener {
Timer timer;
public ImageGallery() {
timer = new Timer(5000, this);
}
#Override
public void actionPerformed(ActionEvent e) {
if (e.getSource() == timer) {
for (int i=0; i<vectorOfImages.size(); i++) {
vectorOfImages.get(i).setImage(AnotherImage);
}
}
}
}

How could I make the colour BLACK be transparent on top of the uploaded image?

Right now all I have is created the black background and uploaded my image I wanted. I want to make it so the image is behind a transparent background. I initially had this all in separate class files but put them all in one main class
package Flashlight;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
public class Flashlight3 extends JFrame {
public class FlashLabelChange extends JPanel {
Flashlight.FlashDisp flashDisp;
public FlashLabelChange(Flashlight.FlashDisp _flashDisp) {
flashDisp = _flashDisp;
JButton btn1 = new JButton("Start");
add(btn1);
class Button implements ActionListener {
public void actionPerformed(ActionEvent event) {
if (event.getActionCommand().equals("Start")) {
flashDisp.UpdateLabel("Start");
}
}
}
ActionListener button = new Button();
btn1.addActionListener(button);
}
}
public class FlashDisp extends JPanel {
private JLabel lblName;
private String sLabel;
private JLabel lblImage;
public FlashDisp() {
lblImage = new JLabel();
add(lblImage);
lblName = new JLabel("Start?");
add(lblName); //add it to the Frame
}
void UpdateLabel(String _sNew) {
sLabel = _sNew;
lblName.setText(sLabel);
}
void UpdateBackground(String _sNew) {
sLabel = _sNew;
if (sLabel == ("Black")) {
setBackground(Color.black);
lblImage.setIcon(new ImageIcon("Hallway.png"));
}
}
}
public class FlashColour extends JPanel {
FlashDisp flashDisp;
public FlashColour(FlashDisp _flashDisp) {
flashDisp = _flashDisp;
setLayout(new GridLayout(3, 1));
JButton btnDark = new JButton("Dark");
add(btnDark);
class ColourChangeListener implements ActionListener {
public void actionPerformed(ActionEvent event) {
if (event.getActionCommand().equals("Dark")) {
flashDisp.UpdateBackground("Black");
}
}
}
ActionListener colourChangeListener = new ColourChangeListener();
btnDark.addActionListener(colourChangeListener);
}
}
public static void main(String[] args) {
JFrame frame = new JFrame();
FlashMain flashMain = new FlashMain();
frame.setSize(400, 400);
frame.setTitle("FLAAAASH LIGHT");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(flashMain);
frame.setVisible(true);
}
}

I think that you need to use the opaque method.
Have a look here
setOpaque(true/false); Java for using opaque.
Hope that helps.

how to change UI depending on combo box selection

In dialog I need to display one group of controls if some combo is checked and another group of controls otherwise.
I.e. I need 2 layers and I need to switch between them when combo is checked/unchecked. How can I do that?
Thanks

CardLayout works well for this, as suggested below.
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
/** #see http://stackoverflow.com/questions/6432170 */
public class CardPanel extends JPanel {
private static final Random random = new Random();
private static final JPanel cards = new JPanel(new CardLayout());
private static final JComboBox combo = new JComboBox();
private final String name;
public CardPanel(String name) {
this.name = name;
this.setPreferredSize(new Dimension(320, 240));
this.setBackground(new Color(random.nextInt()));
this.add(new JLabel(name));
}
#Override
public String toString() {
return name;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
create();
}
});
}
private static void create() {
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
for (int i = 1; i < 9; i++) {
CardPanel p = new CardPanel("Panel " + String.valueOf(i));
combo.addItem(p);
cards.add(p, p.toString());
}
JPanel control = new JPanel();
combo.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
JComboBox jcb = (JComboBox) e.getSource();
CardLayout cl = (CardLayout) cards.getLayout();
cl.show(cards, jcb.getSelectedItem().toString());
}
});
control.add(combo);
f.add(cards, BorderLayout.CENTER);
f.add(control, BorderLayout.SOUTH);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
}