How to close a class the extends JPanel

Question

I am relatively new at java and I am making a HangMan Game but I am facing a problem right now.In particular, I want to close the frame of the program to open a new one when someone finds the word but since my class there extends JPanel dispose() isn't an available solution. So, what should I do to close this frame? ( bare in mind that its object is defined at another class, the one that calls that specific one.) Here is part of my code: ( please forgive me for displaying so many lines ) I just want to know how I can close this window without exiting the whole program, Thanks for your time :) )

EDIT: Thanks guys, I really learned a lot through this '' comment section''. I am grateful for your quick responds and I hope that in the future i will not ask such a silly question again:) PS: I actually used the CardLayout to solve my problem. I don't really see thought how this question is similar to '' How to programmatically close a JFrame '' since in this one I can't use the dispose method because i am extending a JPanel.

 import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
//import java.io.File;
import java.util.*;
import java.util.concurrent.TimeUnit;
public class Game extends JPanel implements Runnable{

public void paintComponent(Graphics g)
{
 super.paintComponent(g);
 this.setBackGround(Color.BLACK);

}


public void run()
{
}
 }

Answer 1

I want to close the frame of the program to open a new one when someone finds the word

The simple answer is, don't. Instead, reset the state of the game to a initial state and update the UI accordiningly

Answer 2

For your problem:

• You can just extend JFrame instead of JPanel.
• You can set the close operation of the JFrame you make in your constructor (frame). Use setDefaultCloseOperation https://docs.oracle.com/javase/7/docs/api/javax/swing/JFrame.html#setDefaultCloseOperation(int)
• You can store the JFrame you have in your constructor as an instance field and call dispose on it later (whenever you need to re-start the game).

Also, using a text field with a keyboard listener or a "submit" button may make this easier - you won't need the 26 letter buttons and the UI would be much more intuitive.

Also, using arrays would make many of your other variables disappear.

Answer 3

Maybe wrap the entire Game class in a parent class that can control the creation of new JFrames, and also the addition of a Game JPanel to it?

That would logically separate the components, because it can be confusing when a component class - to be added to a container - is extended and then proceeds to create its own container (this is actually fine if the UI setup is done once, but possibly not for a repeatable process).

Answer 4

The JPanel alone cannot be visible, you need to have it in some sort of container. This container is received by panel.getParent().

Having that, you can remove yourself from the parent container.

This sample class has a JButton that removes the panel from the view hierarchy when clicked.

public static class APanel extends JPanel {
    public APanel() {
        super();

        JButton btn = new JButton();
        btn.setText("Hello World!");
        btn.addActionListener(e -> {
            ((JButton) e.getSource()).setText("Boo!");
            final Container parent = APanel.this.getParent();
            parent.remove(APanel.this);
            parent.repaint();
        });
        add(btn);
    }
}