Mac / iPhone app - Sync kernel data with iCloud and devices (using master data)

Question

I am working with an iPhone application and a Mac application using basic data.

I would like these 2 applications to synchronize their databases through iCloud storage.

I made adjustments to the implementation of managedObjectContext and persistentStoreCoordinator and added mergeiCloudChanges - from the updated sample recipe code:

 #pragma mark - #pragma mark Core Data stack // this takes the NSPersistentStoreDidImportUbiquitousContentChangesNotification // and transforms the userInfo dictionary into something that // -[NSManagedObjectContext mergeChangesFromContextDidSaveNotification:] can consume // then it posts a custom notification to let detail views know they might want to refresh. // The main list view doesn't need that custom notification because the NSFetchedResultsController is // already listening directly to the NSManagedObjectContext - (void)mergeiCloudChanges:(NSNotification*)note forContext:(NSManagedObjectContext*)moc { NSLog(@"merging iCloud stuff"); [moc mergeChangesFromContextDidSaveNotification:note]; NSNotification* refreshNotification = [NSNotification notificationWithName:@"RefreshAllViews" object:self userInfo:[note userInfo]]; [[NSNotificationCenter defaultCenter] postNotification:refreshNotification]; } /** Returns the managed object context for the application. If the context doesn't already exist, it is created and bound to the persistent store coordinator for the application. */ - (NSManagedObjectContext *)managedObjectContext { if (managedObjectContext != nil) { return managedObjectContext; } NSPersistentStoreCoordinator *coordinator = [self persistentStoreCoordinator]; if (coordinator != nil) { if (IOS_VERSION_GREATER_THAN_OR_EQUAL_TO(@"5.0")) { NSManagedObjectContext* moc = [[NSManagedObjectContext alloc] initWithConcurrencyType:NSMainQueueConcurrencyType]; [moc performBlockAndWait:^{ [moc setPersistentStoreCoordinator: coordinator]; [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(mergeChangesFrom_iCloud:) name:NSPersistentStoreDidImportUbiquitousContentChangesNotification object:coordinator]; }]; managedObjectContext = moc; } else { managedObjectContext = [[NSManagedObjectContext alloc] init]; [managedObjectContext setPersistentStoreCoordinator:coordinator]; } } return managedObjectContext; } // NSNotifications are posted synchronously on the caller thread // make sure to vector this back to the thread we want, in this case // the main thread for our views & controller - (void)mergeChangesFrom_iCloud:(NSNotification *)notification { NSManagedObjectContext* moc = [self managedObjectContext]; // this only works if you used NSMainQueueConcurrencyType // otherwise use a dispatch_async back to the main thread yourself [moc performBlock:^{ [self mergeiCloudChanges:notification forContext:moc]; }]; } /** Returns the managed object model for the application. If the model doesn't already exist, it is created by merging all of the models found in the application bundle. */ - (NSManagedObjectModel *)managedObjectModel { if (managedObjectModel != nil) { return managedObjectModel; } managedObjectModel = [NSManagedObjectModel mergedModelFromBundles:nil]; return managedObjectModel; } - (NSPersistentStoreCoordinator *)persistentStoreCoordinator { if (persistentStoreCoordinator__ != nil) { return persistentStoreCoordinator__; } // assign the PSC to our app delegate ivar before adding the persistent store in the background // this leverages a behavior in Core Data where you can create NSManagedObjectContext and fetch requests // even if the PSC has no stores. Fetch requests return empty arrays until the persistent store is added // so it possible to bring up the UI and then fill in the results later persistentStoreCoordinator__ = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel: [self managedObjectModel]]; // prep the store path and bundle stuff here since NSBundle isn't totally thread safe NSPersistentStoreCoordinator* psc = persistentStoreCoordinator__; NSString *storePath = [[self applicationDocumentsDirectory] stringByAppendingPathComponent:@"MyApp.sqlite"]; // do this asynchronously since if this is the first time this particular device is syncing with preexisting // iCloud content it may take a long long time to download dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{ NSFileManager *fileManager = [NSFileManager defaultManager]; NSURL *storeUrl = [NSURL fileURLWithPath:storePath]; // this needs to match the entitlements and provisioning profile NSURL *cloudURL = [fileManager URLForUbiquityContainerIdentifier:nil]; NSString* coreDataCloudContent = [[cloudURL path] stringByAppendingPathComponent:@"MyApp"]; cloudURL = [NSURL fileURLWithPath:coreDataCloudContent]; NSLog(@"cloudURL: %@", cloudURL); // The API to turn on Core Data iCloud support here. NSDictionary* options = [NSDictionary dictionaryWithObjectsAndKeys:@"xxxxxxxx.com.me.MyApp", @"MyApp", cloudURL, NSPersistentStoreUbiquitousContentURLKey, [NSNumber numberWithBool:YES], NSMigratePersistentStoresAutomaticallyOption, [NSNumber numberWithBool:YES], NSInferMappingModelAutomaticallyOption, nil]; NSError *error = nil; [psc lock]; if (![psc addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL:storeUrl options:options error:&error]) { /* Replace this implementation with code to handle the error appropriately. abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development. If it is not possible to recover from the error, display an alert panel that instructs the user to quit the application by pressing the Home button. Typical reasons for an error here include: * The persistent store is not accessible * The schema for the persistent store is incompatible with current managed object model Check the error message to determine what the actual problem was. */ NSLog(@"Unresolved error %@, %@", error, [error userInfo]); abort(); } [psc unlock]; // tell the UI on the main thread we finally added the store and then // post a custom notification to make your views do whatever they need to such as tell their // NSFetchedResultsController to -performFetch again now there is a real store dispatch_async(dispatch_get_main_queue(), ^{ NSLog(@"asynchronously added persistent store!"); [[NSNotificationCenter defaultCenter] postNotificationName:@"RefetchAllDatabaseData" object:self userInfo:nil]; }); }); return persistentStoreCoordinator__; } 

I can see that the files appear in my directory "/ Users / me / Library / Mobile Documents" when I create / launch myapp.
But I have no idea if it is syncing with iCloud storage - and obviously the data between the iphone and mac are not syncing.
Are there other methods that need to be implemented to transfer data to the cloud?
And is there a way to see which documents are actually in iCloud storage?

Answer 1

Below is a quick partial answer.

You can see what is stored in iCloud:

On Mac:

System Preferences.app → iCloud → click "Manage ...", you will see a list of all applications that have documents stored in Mac OS X or iOS.

In iOS:

Settings → iCloud → Backup and Backup Options → below. Space used. You will then see a list of all applications that have documents stored in Mac OS X or iOS.

While you are using NSFileManager setUbiquitous: itemAtURL: destinationURL: error: documents should be sent to iCloud for you and displayed on other devices.

Answer 2

Another partial answer. Take a look at http://www.raywenderlich.com/6015/beginning-icloud-in-ios-5-tutorial-part-1 if you haven't already. I am working on the same things as you, Mac App and iOS application sharing files. Good luck. Mark

I just found out about: http://mentalfaculty.tumblr.com/archive Find "Under The Sheets" CoreData and iCloud. Check this!

Answer 3

OK, my code looks a bit different, I have it in a separate class to reuse it for all my projects. However, if iCloud is enabled (URLForUbiquityContainerIdentifier: nil return not nil), I configure my NSPsistentStoreCoordinator as follows:

 // ---- iCloud Setup // fist container in entitlements NSURL *iCloudDirectoryURL = [[NSFileManager defaultManager] URLForUbiquityContainerIdentifier:nil]; // if iCloud is enabled setup the store if (iCloudDirectoryURL) { __iCloudEnabled = true; NSLog(@"iCloud:%@", [iCloudDirectoryURL absoluteString]); // AppDelegate has to provide the contentnamekey NSString *contentNameKey = [appDelegate dataStoreContentNameKey]; options = [NSDictionary dictionaryWithObjectsAndKeys:contentNameKey, NSPersistentStoreUbiquitousContentNameKey, iCloudDirectoryURL, NSPersistentStoreUbiquitousContentURLKey, nil]; } 

I am skipping where you are setting up NSPersistentStoreUbiquitousContentNameKey.

Secondly, I understand that this only works on the device, and your app ID should include iCloud.