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iossynchronizationicloud

Synchronization via Icloud between 2 devices IOS

I have a problem. I need to make the synchronization between the two devices

At first I was trying to set up synchronization through СoreData. But it's not a very good work. Adding new entities worked fine. But the editing of previously created work is not good.

I looked as done in other applications. And I saw that in the majority of synchronization is implemented through .entry file . What is this format is that? I tried to find information about it, and how to create it. But I could not find it. Please tell me how is synchronized through .entry . Maybe there are some tutorials.

Thank you for your time

Added Image Example this files in iCloude. It's file created one well-known application enter image description here

Solution

  • These .entry files are not publicly part of any iCloud API, so no information is available on them. In fact if I Google for "iCloud .entry", this question is currently the #1 result (and the only one in the top 10 that is even remotely relevant).

    Since these apps appear to be using iCloud, and since the file in question is a PNG, it's very likely that the apps are using iCloud file synchronization and that the .entry files are an undocumented internal implementation detail. They aren't something you create or use directly, but are (probably) something that iCloud uses for bookkeeping when you're using the file sync API.

    To use this API, the basic steps are:

    1. Create the file locally
    2. Use NSFileManager to move the local file to iCloud
    3. Use NSMetadataQuery to find files in iCloud that haven't been downloaded yet
    4. Use NSFileManager to download iCloud files to the local device.

    Apple provides a lot of documentation on this process, plus WWDC videos and sample code.

    This is nothing like Core Data syncing. You can't sync a Core Data persistent store file this way-- Apple specifically warns that it's likely to get corrupted. But you can use it for most other types of documents.