Core Data: could not locate an NSManagedObjectModel for entity name 'XXX'

The following code is a simple trick to solve this issue. Add it to viewDidLoad or somewhere the code to access the entity.

if (managedObjectContext == nil)   { 

        managedObjectContext = [(YourAppDelegate *)[[UIApplication sharedApplication] delegate] managedObjectContext]; }

Remember to import "YourAppDelegate.h" !!!