iPhone CoreData: How can I track/observe all changes within a subgraph?

Posted by D Carney on Stack Overflow See other posts from Stack Overflow or by D Carney
Published on 2010-03-17T16:19:58Z Indexed on 2010/03/17 16:21 UTC
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nsmanagedobject

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nsmanagedobjectcontext

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iphone

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coredata

I have a NSManagedObjectContext in which I have a number of subclasses of NSManagedObjects such that some are containers for others. What I'd like to do is watch a top-level object to be notified of any changes to any of its properties, associations, or the properties/associations of any of the objects it contains.

Using the context's 'hasChanges' doesn't give me enough granularity. The objects 'isUpdated' method only applies to the given object (and not anything in its associations). Is there a convenient (perhaps, KVO-based) was I can observe changes in a context that are limited to a subgraph?

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