How can I know NSWindow was closed using the close button ?

Question

Is there an easy way to know when a NSWindow was closed using the close button (of the window title bar) .

Using NSWindowDelegate and the windowWillClose:(NSNotification *)notification method I get notification of each closing. But how can I know the closing request was send by the close button

Answer 1

Use [yourWindow standardWindowButton:NSWindowCloseButton] to find the close button, then change its target and action to a custom method.