nsmanagedobjectcontext

I have an NSManagedObjectContext associated to main thread ( mainContext ), where I fetch all the NSManagedObject I show throughout the app. Users don't edit these objects, but I get updates from web services. I periodically perform asynchronous calls to such services, and they "tell" me which of my managed objects have to be deleted (if any), which of them have to be updated with new information (if any), and if I need to insert new objects. So, I need to firstly get the responses of all the services and then check what changes I have to make to the managed objects I already have in my

How to return the new object saved in coredata if I am using performBlock to save a managedObjectContext? The requirement is, add an entry in coredata, and return it. My code is something like this: //create a privateMOC NSManagedObjectContext *private = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSPrivateQueueConcurrencyType]; //set parentContext [private setParentContext:self.coredataManager.managedObjectContext]; __block Detail *object = nil; [private performBlock:^{ //fetch from the db object = [self.coredataManager insertObjectWithEntityName:NSStringFromClass([Detail class])]

I get the following error: 'NSInvalidArgumentException', reason: 'Illegal attempt to establish a relationship 'condition' between objects in different contexts when running my iphone app. The relevant part of my model looks like this: AssessmentTree -has one TreeCrown TreeCrown -has one TreeCrownCondition -has one AssessmentTree TreeCrownCondition -has many TreeCrowns For the sake of context, I'll mention that this part of the model is designed to allow an arborist to record the condition of a tree's crown. It stores a list of options for assessing the tree crown that can also be edited by the

My program does work like link below: Update results of NSFetchedResultsController without a new fetch show result of NSFetchedResultsController to UITableView get new object from web service and store it to core data (in same view controller, with RestKit) update table view with notification of NSFetchedResultsController delegate The implementation of NSFetchedResultsControllerDelegate is copied from Apple's Core Data project and my predicated is: [NSPredicate predicateWithFormat:@"isMyTest == TRUE"] If the property update goes from TRUE to FALSE, it removes rows from the tableview (because

I am creating a framework that allows me to use Core Data. In the framework's test target, I have configured a data model named MockModel.xcdatamodeld . It contains a single entity named MockManaged that has a single Date property. So that I can test my logic, I am creating an in-memory store. When I want to validate my saving logic, I create an instance of the in-memory store and use it. However, I keep getting the following output in the console: 2018-08-14 20:35:45.340157-0400 xctest[7529:822360] [error] warning: Multiple NSEntityDescriptions claim the NSManagedObject subclass

I have a saveMOC which is the direct parent of a mainMOC , and I need for online fetch another tmpMOC in order not to block my UI whilst fetching a ton of records from the Internet. My app freezes. I could narrow it to this very point: fetchedItems = [tmpMOC executeFetchRequest:fetchRequest error:&error]; I tried to enclose this within dispatch_sync , [moc.parentcontext.parentcontext.persistentStoreCoordinator lock/unlock] , [whatevermoc performBlockAndWait] ... I also try to fetch the _mainMOC ... No way... I understand that executeFetchRequest is not thread safe, so, how do I lock whatever I

I want to use the singleton UIApplication to access the managedObjectContext of the AppDelegate. But when I write [[[UIApplication sharedApplication] delegate] managedObjectContext] or [[[UIApplication sharedApplication] delegate] __managedObjectContext] it doesn't work. But this line works fine : NSLog(@"Seeking for the AppDelegate : %@", [[[UIApplication sharedApplication] delegate] class]); Do you have a solution ? Niels Try casting it to your actual app delegate implementation, like [(MyAppDelegate *)[[UIApplication sharedApplication] delegate] managedObjectContext]; And to add #import