103

I want to call a method confirmExit() when the red close button of the title bar of a JFrame is clicked.

How can I capture that event?

I'd also like to prevent the window from closing if the user chooses not to proceed.

DaveyDaveDave
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alxcyl
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6 Answers6

172
import javax.swing.JOptionPane;
import javax.swing.JFrame;

/*Some piece of code*/
frame.addWindowListener(new java.awt.event.WindowAdapter() {
    @Override
    public void windowClosing(java.awt.event.WindowEvent windowEvent) {
        if (JOptionPane.showConfirmDialog(frame, 
            "Are you sure you want to close this window?", "Close Window?", 
            JOptionPane.YES_NO_OPTION,
            JOptionPane.QUESTION_MESSAGE) == JOptionPane.YES_OPTION){
            System.exit(0);
        }
    }
});

If you also want to prevent the window from closing unless the user chooses 'Yes', you can add:

frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
Juan
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Ravindra Gullapalli
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  • If want the program to only close this frame and not entirely stop, use `frame.dispose()` instead of `System.exit(0)` – AirOne May 01 '22 at 17:44
26

Override windowClosing Method.

public void windowClosing(WindowEvent e)

It is invoked when a window is in the process of being closed. The close operation can be overridden at this point.

Shashank Kadne
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    Will this work if the user closes the application (for example, by hitting Cmd + Q on a Mac)? Does the class that implements this method have to declare `implements WindowListener` for this code to work? If so, it might be good to include that in the answer. Otherwise this is an elegant solution. – intcreator Nov 20 '15 at 21:42
  • @brandaemon If you add this line of code to the top of your main() method "System.setProperty("apple.eawt.quitStrategy", "CLOSE_ALL_WINDOWS");" then it will call the windowListener when Cmd + Q is pressed on mac. – retrovius Jul 17 '18 at 18:59
2

This may work:

jdialog.addWindowListener(new WindowAdapter() {
    public void windowClosed(WindowEvent e) {
        System.out.println("jdialog window closed event received");
    }

    public void windowClosing(WindowEvent e) {
        System.out.println("jdialog window closing event received");
    }
});

Source: https://alvinalexander.com/java/jdialog-close-closing-event

Phidippus
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1

This is what I put as a menu option where I made a button on a JFrame to display another JFrame. I wanted only the new frame to be visible, and not to destroy the one behind it. I initially hid the first JFrame, while the new one became visible. Upon closing of the new JFrame, I disposed of it followed by an action of making the old one visible again.

Note: The following code expands off of Ravinda's answer and ng is a JButton:

ng.addActionListener((ActionEvent e) -> {
    setVisible(false);
    JFrame j = new JFrame("NAME");
    j.setVisible(true);
    j.addWindowListener(new java.awt.event.WindowAdapter() {
        @Override
        public void windowClosing(java.awt.event.WindowEvent windowEvent) {
            setVisible(true);
        }
    });
});
Jonny Henly
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Cody
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1
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

also works. First create a JFrame called frame, then add this code underneath.

Russell
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0

Try this:

setDefaultCloseOperation(DO_NOTHING_ON_CLOSE);

It will work.

Dr.jacky
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