Reputation: 2412
I developed core data based app and implemented iCloud sync feature after it was introduced in iOS 13.
I enabled iCloud kit, used NSPersistentCloudKitContainer
instead of NSPersistentContainer
and added several lines of code to sync core data with iCloud.
Sync works fine. The problem is that when I uninstall app and reinstall app, it doesn't fetch iCloud data at first time. I have to restart app or open another screens to let Core Data to be synced with iCloud. Is there anyway I can check if core data is being synced with iCloud or wait until it finishes syncing?
Thanks.
Upvotes: 15
Views: 4697
Reputation: 7
I have to restart app or open another screens to let Core Data to be synced with iCloud.
To solve this I'm using a notification observer for NSManagedObjectContextObjectsDidChange
event.
When reinstalled app is first opened, it shows empty screen and after some time, when data is synced, the notification is triggered and the page is reloaded with the data.
However I also couldn't find any way to wait and show loading message while data is being synced.
Upvotes: 0
Reputation: 1
Currently, there is no API provided for iCloud sync completion. What you can do is
You can initialize NSPersistentCloudKitContainer and call it's loadPersistentStores() at the start of the app. This will buy you enough time and your data will be available for your internal screens.
You can also listen for remote changes in your local store and update your UI accordingly as mentioned in this Apple doc: https://developer.apple.com/documentation/coredata/consuming_relevant_store_changes
Upvotes: 0
Reputation: 11557
There is no API exposed to get the completion handler on sync of all CKRecord's to NSManagedObject's.
Also the update is working using a background silent notification so we can expect any change anytime. So its good to not having completion handler
You can create one attribute to check the sync time, just like a date when last sync happened to local record
and check the lastModificationDate
(By default CKRecord has this property) of the same record in iCloud.
So everytime when you launch the app check for all the records manually if any update is required, then wait for notification of update and keep on checking the sync status
Note: Be careful this may lead to delay your launch process if from any other device user is very active and new records are getting inserted or modified.
Upvotes: 5