How to programmatically close a JFrame

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What's the correct way to get a JFrame to close, the same as if the user had hit the X close button, or pressed Alt+F4 (on Windows)?

I have my default close operation set the way I want, via:

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

It does exactly what I want with the aforementioned controls. This question isn't about that.

What I really want to do is cause the GUI to behave in the same way as a press of X close button would cause it to behave.

Suppose I were to extend WindowAdaptor and then add an instance of my adaptor as a listener via addWindowListener(). I would like to see the same sequence of calls through windowDeactivated(), windowClosing(), and windowClosed() as would occur with the X close button. Not so much tearing up the window as telling it to tear itself up, so to speak.

17 Answers

If you want the GUI to behave as if you clicked the X close button then you need to dispatch a window closing event to the Window. The ExitAction from Closing An Application allows you to add this functionality to a menu item or any component that uses Actions easily.

frame.dispatchEvent(new WindowEvent(frame, WindowEvent.WINDOW_CLOSING));
setVisible(false); //you can't see me!
dispose(); //Destroy the JFrame object

Not too tricky.

If by Alt-F4 or X you mean "Exit the Application Immediately Without Regard for What Other Windows or Threads are Running", then System.exit(...) will do exactly what you want in a very abrupt, brute-force, and possibly problematic fashion.

If by Alt-F4 or X you mean hide the window, then frame.setVisible(false) is how you "close" the window. The window will continue to consume resources/memory but can be made visible again very quickly.

If by Alt-F4 or X you mean hide the window and dispose of any resources it is consuming, then frame.dispose() is how you "close" the window. If the frame was the last visible window and there are no other non-daemon threads running, the program will exit. If you show the window again, it will have to reinitialize all of the native resources again (graphics buffer, window handles, etc).

dispose() might be closest to the behavior that you really want. If your app has multiple windows open, do you want Alt-F4 or X to quit the app or just close the active window?

The Java Swing Tutorial on Window Listeners may help clarify things for you.

Not only to close the JFrame but also to trigger WindowListener events, try this:

myFrame.dispatchEvent(new WindowEvent(myFrame, WindowEvent.WINDOW_CLOSING));
 setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
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