iCloud not syncing properly for Core Data (iOS7)

Question

I\'m attempting to sync Core Data among devices using iCloud (using the new iOS7 method). I\'m still seeing issues with the syncing when testing with the simulators. Sometimes d

Answer 1

Here is how I do it. It might be an easy way to simplify and unclutter your code.

self.managedObjectContext = [[NSManagedObjectContext alloc] 
                            initWithConcurrencyType:NSMainQueueConcurrencyType];
self.managedObjectContext.mergePolicy = NSMergeByPropertyObjectTrumpMergePolicy;
self.managedObjectContext.persistentStoreCoordinator = 
                            [[NSPersistentStoreCoordinator alloc] 
                            initWithManagedObjectModel:self.managedObjectModel];

[self.managedObjectContext.persistentStoreCoordinator 
    addPersistentStoreWithType:NSSQLiteStoreType
    configuration:nil
    URL:self.storeURL
    options:@{ NSPersistentStoreUbiquitousContentNameKey : @"iCloudStore" }
    error:&error];

The only iCloud bit is the options parameter. (I removed other options for clarity.) The store URL is just [documentsDirectory URLByAppendingPathComponent:@"Store.sqlite"].

I am also listening to these:

NSPersistentStoreDidImportUbiquitousContentChangesNotification
NSPersistentStoreCoordinatorStoresWillChangeNotification
NSPersistentStoreCoordinatorStoresDidChangeNotification

In the first one, I call

[self.managedObjectContext mergeChangesFromContextDidSaveNotification:note];

and post another notification to update the UI; in the second one, I save; in the third one I also update the UI.

For me that's really all there is to it. It works flawlessly up to now.

Credit goes to iCloudCoreDataStack.