Retaining an NSWindow size and state - looking for an elegant way to do this

I have a controller class which spawns a window when a certain condition occurs. This window can be closed by the user, moved around or resiz开发者_高级运维ed.

Ideally, when this condition occurs, I'd like the window to re-open in the same spot the user closed it last time.

Looking for an elegant way to do this. Pointers (or references) will be most welcome.

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Luckily, AppKit knows this is a common pattern and has provided -setFrameAutosaveName:, which does this automatically for you. (If you're using NSWindowController you'll want to call setShouldCascadeWindows:NO, which will override this.)