Where do you put cleanup code for NSDocument sub-classes?

Question

I have a document-based application and I have sub-classed NSDocument and provided the required methods, but my document needs some extensive clean-up (needs to run external tasks etc). Where is the best place to put this? I have tried a few different methods such as:

• close
• close:
• canCloseDocumentWithDelegate:shouldCloseSelector:contextInfo
• dealloc

If I put it in dealloc, sometimes it gets called and other times it does not (pressing Command+Q seems to bypass my document's deallocation), but it is mandatory that this code gets called without failure (unless program unexpectedly terminates).

Answer 1

Have each document add itself as an observer in the local notification center for NSApplicationWillTerminateNotification. In its notification method, call its clean-up method (which you should also call from dealloc or close).