SharedCoreData using OSX app and iOS App

Question

I am using the source code from https://github.com/jab5990/TestCDiCloud.git. Apparently this source code is the sample code from the WWDC 2012 Session #227 called Using iCloud with Core Data. The original source code does not seem to be available on Apple's website any longer.

I am new to Core Data and I struggle quite a bit with these concepts. The situation is that the data does not get refreshed while both apps are running:

1. I add data to my mac app (2 first rows)
2. I start the iPhone 7 app in the simulator (after signing in to iCloud)
3. The entries from the mac show up
4. I add more data to the mac app
5. The data does not show up after several minutes

So on in DetailViewController.m:204 on the iPhone App the Notification NSPersistentStoreDidImportUbiquitousContentChangesNotification is registered, which should mean that changes from the Mac app should be incorporated.

How do I ensure that the data stays in sync.

Answer 1

In the simulator sometimes you need to use the Debug -> Trigger iCloud Sync menu to trigger the sync. It is not automatic like on iOS devices.

If you keep having issues then try these sample apps which include code for handling iCloud account switches, moving from local to iCloud, making backups, storing and fetching backup files in iCloud, etc...

http://ossh.com.au/design-and-technology/software-development/sample-library-style-ios-core-data-app-with-icloud-integration/

BTW that wwdc2012 session is old so I would look at the more recent wwdc2013 session 207 video for things that have changed in iOS7, OSX 10.9

Answer 2

iCloud can take quite some time to transfer files, and then the Core Data framework has to get around to actually importing the files. So several minutes or even longer is not unheard of for a delay.

You can use Xcode to trigger a sync with the Debug menu. That may help. Otherwise, you probably just have to wait, or perhaps quit and relaunch the app.

Welcome to the wonderful world of iCloud debugging.