Tutorial 3: Question on NSFetchedResultsController

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1

Hi,

I’m implementing NSFetchedResultsController for my CoreData (pg ~182) and I am hoping someone could help clarify HOW NSFetchedResultsController is able to tell its delegate that changes are being made to Core Data. I see that it’s only getting called in ViewDidLoad - so how would it know when something has been added/edited? Is it constantly monitoring the data? Why don’t we need to add something to the LocationDetailsViewController done() method?

Thanks!

2

A little later on in the tutorial you’ll learn about notifications. Core Data sends out notifications whenever the data changes. NSFetchedResultsController listens to such notifications and then calls the delegate. (You can also listen to these notifications yourself.)

3

I see - thanks for the fast response!