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POGetting runtime error when doing fast enumeration over an NSArray of entities from Core Data in iOS
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copied!<p>I have an NSArray of Objects of type NSManagedObject that are returned from a fetch result I perform in Core Data. The NSArray contains objects, as I am able to verify this after the query by printing the contents of the NSArray to the console. My problem however is that I am unable to do fast enumeration over this array using objects of the type of entity that I have retrieved from the query. The exact error I am getting at runtime is the following:</p> <pre><code>Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[My_Entity_Name countByEnumeratingWithState:objects:count:]: unrecognized selector sent to instance 0xa9f0090' </code></pre> <p>My for loop that I am using doesn't even get to run because it breaks at the for loop condition:</p> <pre><code>for (MyEntityType *entityType in self.entityArray) { ... } </code></pre> <p>The actual fetch command I use to populate the array self.entityArray is:</p> <pre><code>self.entityArray = [[Singleton sharedInstance] retrieveEntities:self.mainEntity.relationshipEntity.relationshipEntityId]; </code></pre> <p>in turn, this is how my retrieveEntity method looks like:</p> <pre><code>- (NSArray *)retrieveEntities:(NSNumber *)relationshipEntityAttributeId { NSManagedObjectContext *context = [[DataEngine sharedInstance] managedObjectContext]; NSError *error; // Create fetch request NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:ENTITY_NAME inManagedObjectContext:context]; [fetchRequest setEntity:entity]; // Create predicate NSPredicate *pred = [NSPredicate predicateWithFormat:@"relationshipEntity.relationshipAttributeId == %@", relationshipEntityAttributeId]; [fetchRequest setPredicate:pred]; NSArray *items = [context executeFetchRequest:fetchRequest error:&error]; if ([items count]>0) { return items[0]; } else { return nil; } } </code></pre> <p>Can anyone see why I am getting the above error?</p> <p>Thanks in advance to all who reply.</p>

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