JFrame making it do an action on exit

[kris5228]

Hello,

I want to make my program do something else than

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

How do i call a class from another java file when pressing the X?

I've already made a file that looks like this:

public class Exit
{
    private static Main mainfile = new Main();

    public void onexit()
    {
        if (mainfile.fn.equals("unnamed"))
        {
            Object[] options = { "SAVE", "NO", "CANCEL"};

            JOptionPane.showOptionDialog(null, "Do you want to save " + mainfile.fn + "?", "Warning",
                                        JOptionPane.DEFAULT_OPTION, JOptionPane.WARNING_MESSAGE, null, options, options[0]);
        }
        else
        {
            mainfile.frame.dispose();
        }
    }
}

All i need is to make the Exit Button execute that.

[doWhile]

Use a window listener
How to Write Window Listeners (The Java™ Tutorials > Creating a GUI With JFC/Swing > Writing Event Listeners)

[kris5228]

Thank you!