Develop Reference

How to mimic the behavior of JPopupMenu with JDialog?

I'm implementing an "in app" search engine with Swing and I want it to behave exactly like Windows 10's search box.
The search box should:
Open above and to the right of the search button, touching the button's edge.
Have the focus when open.
Close (if open) on a press of the search button.
Close (if open) when pressing with the mouse anywhere out of the search box.
It was perfect if JPopUpMenu could have JDialog as it's child but since it can't I need to implement the behaviors from scratch (or do I?).
This is my first time using Swing and I'm having difficulties implementing everything by myself.
I tried looking for examples online but I couldn't find much helpful information.
Is there a workaround to the fact that JPopUpMenu can't host JDialog?
Are there examples of implementing the behaviors I described?
Thanks
===============================Edit============================
Thanks for the comments so far. I've managed to get the behavior I wanted except one issue.
The following code creates a frame with a button:
public static void main(String[] args){
JFrame mainWindow = new JFrame();
mainWindow.setSize(420,420);
mainWindow.setVisible(true);
JFrame popUp = new JFrame();
popUp.setSize(210, 210);
JButton button = new JButton("button");
mainWindow.add(button);
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
if(!button.isSelected()){
button.setSelected(true);
popUp.setVisible(true);
}
else{
button.setSelected(false);
popUp.setVisible(false);
}
}
});
popUp.addWindowFocusListener(new WindowAdapter() {
#Override
public void windowLostFocus(WindowEvent e) {
popUp.setVisible(false);
}
});
}
When I click the button, a pop-up window appears and if I click out of the main window the pop up disappear but then when I want to re-open the pop-up I need to press the button twice.
How can I get the button to operate correctly when the pop-up was closed due to lose of focus?

Your "solution" is very brittle. Try moving the main JFrame before left-clicking on the JButton.
Oracle has a helpful tutorial, Creating a GUI With Swing. Skip the Netbeans section. Study the rest of the tutorial.
I created a main JFrame that pops up a JDialog. I put the close JButton on the JDialog. The JDialog is modal, meaning you cannot access the main JFrame while the JDialog is visible.
You can place the JDialog anywhere you wish on the screen. Normally, you have a JDialog appear in the center of the parent JFrame. That's where users expect a dialog to appear. I placed the JDialog towards the upper left, just to show you how it's done.
Here's the complete runnable code.
import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class PopupExample {
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> new PopupExample().createAndShowGUI());
}
private JFrame mainWindow;
public void createAndShowGUI() {
mainWindow = new JFrame("Main Window");
mainWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mainWindow.add(createMainPanel(), BorderLayout.CENTER);
mainWindow.pack();
mainWindow.setLocationByPlatform(true);
mainWindow.setVisible(true);
}
private JPanel createMainPanel() {
JPanel panel = new JPanel(new FlowLayout());
panel.setBorder(BorderFactory.createEmptyBorder(200, 200, 200, 200));
JButton button = new JButton("button");
panel.add(button);
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
createAndShowDialog(mainWindow);
}
});
return panel;
}
private void createAndShowDialog(JFrame frame) {
JDialog dialog = new JDialog(frame, "Dialog", true);
dialog.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
dialog.add(createDialogPanel(dialog), BorderLayout.CENTER);
dialog.pack();
// Here's where you set the location of the JDialog relative
// to the main JFrame
Point origin = frame.getLocation();
dialog.setLocation(new Point(origin.x + 30, origin.y + 30));
dialog.setVisible(true);
}
private JPanel createDialogPanel(JDialog dialog) {
JPanel panel = new JPanel(new FlowLayout());
panel.setBorder(BorderFactory.createEmptyBorder(100, 100, 100, 100));
JButton button = new JButton("Close");
panel.add(button);
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
dialog.dispose();
}
});
return panel;
}
}

Weird Issue with JComponent Visibility

I am working on a GUI project with Swing in Java and the program is generally working fine. However, under each screen, I have a back button that calls the method of the screen before it and goes through the ArrayList containing all of the elements on the current screen and calls setVisible(false) on them. Upon running the program, the back button works correctly if you click it once but if you go back on the screen, and click it again, it takes two clicks for it to correctly work and then four clicks and then eight clicks and so on. I have no idea what is going on or why it is behaving this way as nothing in my code seems to do it. Also, sometimes, the button correctly returns to the previous screen but then keeps the components on the current screen active as if setVisible(false) was never called. The following code represents the general structure of my project. Is there anything that it is doing that is generating this problem?
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.*;
public class MAIN {
static JFrame frame;
static JPanel panel;
public static void main(String [] args) {
mainScreen();
}
public static void mainScreen() {
JButton newScreen = new JButton("Next Screen");
frame = new JFrame();
panel = new JPanel();
panel.setBounds(0,0,1920,1080);
panel.setBackground(Color.cyan);
newScreen.setBounds(50, 500, 100, 500);
newScreen.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
newScreen.setVisible(false);
JButton returnButton = new JButton("return");
returnButton.setBounds(50, 50, 100, 100);
panel.add(returnButton);
returnButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
returnButton.setVisible(false);
mainScreen();
}
});
}
});
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
panel.add(newScreen);
frame.add(panel);
frame.setSize(1920,1080);
frame.setLayout(null);
frame.setVisible(true);
}
}

how to define action listener for buttons in java

I have a jframe that includes JButton.I have six buttons in this frame, but I don't know how to define action listener for this buttons.please help to solve this problem.

First you have to import the package java.awt.event.* to enable events. After the class name you have to add implements ActionListener so that the class can handle events. When you have created the buttons you have to add an actionlistener to each button. Since you haven't showed which code you use I make an example with a simple program that counts votes, if the user clicks the yesButton the votes are increased with 1 and if the user clicks the noButton the votes are decreased with 1.
Here is the code to add an ActionListener to each button:
yesButton.addActionListener(this);
noButton.addActionListener(this);
Then write the following code to handle the events:
public void actionPerformed(ActionEvent e) {
JButton src = (JButton) e.getSource();
if(src.getActionCommand().equals("Yes")) {
yesCount++;
} else {
noCount++;
}
label.setText("Difference: " + (yesCount - noCount));
}
If you have 6 buttons you need to have an if statement and then 5 "else if" statements instead of only an if and an else statement.

Have a look at the Java tutorials on how to use ActionListeners:
https://docs.oracle.com/javase/tutorial/uiswing/events/actionlistener.html
Here's a simple example:
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Hello extends JPanel implements ActionListener {
JButton button;
public Hello() {
super(new BorderLayout());
button = new JButton("Say Hello");
button.setPreferredSize(new Dimension(180, 80));
add(button, BorderLayout.CENTER);
button.addActionListener(this); // This is how you add the listener
}
/**
* Invoked when an action occurs.
*/
public void actionPerformed(ActionEvent e) {
System.out.println("Hello world!");
}
private static void createAndShowGUI() {
JFrame frame = new JFrame("Hello");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JComponent newContentPane = new Hello();
newContentPane.setOpaque(true);
frame.setContentPane(newContentPane);
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}

buttons have a method called addActionListener, use that for adding the action listener that you can implement for the click...
Example:
dummyButton = new JButton("Click Me!"); // construct a JButton
add(dummyButton); // add the button to the JFrame
dummyButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
System.out.println(" TODO Auto-generated method stub");
}
});

It's really simple.
I suppose you have an instance of your button, right? Let's say that instance is called myButton.
You can just add an action listener by calling addActionListener:
myButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// Do whatever you like here
}
});
Protip: next time you don't know what method to call, just type the instance name and .. Then, your IDE will show you all the methods you can call, unless you are not using an IDE. If that is the case, download one.

Java - Close Window on Event

people of the internet.
I want to have a sort of start screen for a game ive been writing. Thus far it features 4 Buttons for each one of the 4 Players that change color on click from red to green and vice versa representing their individual "ready"-status if that makes sense. I used JFrame and JButtons.
Now i want that window to close if every one of those Buttons is currently set to "ready" aka button.getBackground() == Color.GREEN.
Any suggestions as to which EventListeners to use for this/implementation tips/code snippets would be greatly appreciated since my research on Windowclosing on Event didnt bring up much for me.
Thank you in advance and Greetings.

Since you're awaiting and acting on button presses, the most logical listener would be an ActionListener.
Consider making the buttons JToggleButtons, and then in your listener querying each button to see if it is selected (isSelected()) and if so, launch your program. As a side bit, I'd consider making the intro window a JDialog and not a JFrame, either that or making it a JPanel and swapping it out via a CardLayout when necessary.
For example:
import java.awt.Color;
import java.awt.Dialog.ModalityType;
import java.awt.Dimension;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.*;
public class AreWeReady extends JPanel {
List<AbstractButton> buttons = new ArrayList<>();
private int userCount;
public AreWeReady(int userCount) {
this.userCount = userCount;
ButtonListener buttonListener = new ButtonListener();
for (int i = 0; i < userCount; i++) {
JButton btn = new JButton("User " + (i + 1));
buttons.add(btn);
btn.addActionListener(buttonListener);
add(btn);
}
}
private class ButtonListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
AbstractButton btn = (AbstractButton) e.getSource();
Color c = Color.GREEN.equals(btn.getBackground()) ? null : Color.GREEN;
btn.setBackground(c);
for (AbstractButton button : buttons) {
if (!Color.GREEN.equals(button.getBackground())) {
// if any button does not have a green background
return; // leave this method
}
}
// otherwise if all are green, we're here
Window win = SwingUtilities.getWindowAncestor(btn);
win.dispose();
// else launch your gui
}
}
private static void createAndShowGui() {
int userCount = 4;
AreWeReady areWeReadyPanel = new AreWeReady(userCount);
JFrame frame = new JFrame("Main Application");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
frame.getContentPane().add(Box.createRigidArea(new Dimension(400, 300)));
frame.pack();
frame.setLocationByPlatform(true);
JDialog dialog = new JDialog(frame, "Are We Ready?", ModalityType.APPLICATION_MODAL);
dialog.add(areWeReadyPanel);
dialog.pack();
dialog.setLocationByPlatform(true);
dialog.setVisible(true);
// this is only reached when the modal dialog above is no longer visible
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}

Java JButton - making simple menu

Hi take a look on this code:
package arkanoid;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.Color;
import java.awt.event.*;
public class Arkanoid extends JFrame
{
private static final long serialVersionUID = 6253310598075887445L;
static JFrame frame;
static class Action1 implements ActionListener {
public void actionPerformed (ActionEvent e) {
//frame = new JFrame("Arkanoid");
frame.setLocationRelativeTo(null);
frame.setIgnoreRepaint(true);
frame.setResizable(false);
frame.setVisible(true);
frame.setSize(500,400);
frame.add(new Gra());
}
}
static class Action2 implements ActionListener {
public void actionPerformed (ActionEvent e) {
frame.dispose();
System.exit(0);
}
}
public static void main(String[] args)
{
//new Arkanoid();
frame = new JFrame("Arkanoid");
frame.setSize(500,400);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setTitle("Arkanoid BETA");
frame.setLocationRelativeTo(null);
frame.setIgnoreRepaint(true);
frame.setResizable(false);
frame.setVisible(true);
JPanel panel = new JPanel();
frame.add(panel);
JButton button = new JButton("Nowa Gra");
panel.add(button);
button.addActionListener (new Action1());
JButton button2 = new JButton("Wyjscie");
panel.add(button2);
button2.addActionListener (new Action2());
}
}
This code almost works, I want to make a button2 a quit button working like X button in top right frame's icons and button1 need to open a Gra() in the same window. When im doing it like this it isnt work fine:/ i need to click 2 times on button1 to go to Gra() and what is more KeyListeners in Gra() arent working :(
Im new in buttons, frames and panels in java so please help with this code. Correct it please.

There are a number of fundamental problems with your code, the least of which is why your button1 requires 2 clicks.
However, for your problem you should try rearranging the order of your button1 listener, so that your Component is added to the frame first, before setting it to be visible. An example that should work:
static class Action1 implements ActionListener {
public void actionPerformed (ActionEvent e) {
frame.add(new Gra());
frame.revalidate();
}
}
Note you have already set the size, location etc of frame in main, so there is no need to set them again every time the button is clicked.
I stress that there are more important problems with your code than this issue. You should take a look at Java's Modifier Types (static does not seem applicable here), as well as object-oriented concepts such as inheritance (you define your Arkanoid class to extend JFrame, yet have a JFrame object as a class variable).

I want to make a button2 a quit button working like X button in top right frame's
You can use the ExitAction class found in Closing an Application.
For other examples of how to use buttons read the Swing tutorial on How to Use Buttons. This is the place to start for all you Swing related questions.

There are many problems with your code. I've refactored it a little. With below code & #ricky116 answer I think you should get all of them.
import javax.swing.*;
import java.awt.Color;
import java.awt.event.*;
public class Arkanoid extends JFrame
{
public Arkanoid() {
super("Arkanoid");
setSize(500,400);
setTitle("Arkanoid BETA");
setLocationRelativeTo(null);
setResizable(false);
final JPanel panel = new JPanel();
setContentPane(panel);
panel.add(new JButton(new AbstractAction("Nowa Gra") {
public void actionPerformed (ActionEvent e) {
panel.removeAll();
panel.add(new Gra());
panel.revalidate();
panel.repaint();
}
});
panel.add(new JButton(new AbstractAction("Wyjscie") {
public void actionPerformed (ActionEvent e) {
Arkanoid.this.setVisible(false);
}
});
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable() {
public void run() {
Arkanoid frame = new Arkanoid();
frame.setVisible(true);
}
});
}
}