IOS swift: save cache using coredata (cloud)

Question

I learned to use cloudkit to save and retrieve records, but I was confused about saving the cache in coredata.

For example, I extracted several records and displayed several attributes of this type of record (say, A, C, and F) using a table. And when I click on the cell, it will show this entry (all attributes of this entry: ABCDEF, but not including the entry of reference attributes). I was wondering if these things should be stored in coredata when I first took the record: "ACF and recordID"? And when the user clicks to see the details, do I get again using recordID? And the key point is, what type of attribute should I use to store CKRecordID / CKRecord?

I know that I could store things like the image in a local cache file (also confusing ..), but is this not a permanent store? And the reason why I did not store the record of all attributes directly is that this record is an “invitation” only if the user decides to accept it, it will load all attributes, including attributes of the reference type. Any help would be helpful, thanks!

Answer 1

You should only archive system fields during caching, for example:

private func dataFromRecord(record:CKRecord) -> NSData{ let archivedData = NSMutableData() let archiver = NSKeyedArchiver(forWritingWithMutableData: archivedData) archiver.requiresSecureCoding = true record.encodeSystemFieldsWithCoder(archiver) archiver.finishEncoding() return archivedData } private func recordFromData(archivedData:NSData) -> CKRecord?{ let unarchiver = NSKeyedUnarchiver(forReadingWithData: archivedData) unarchiver.requiresSecureCoding = true let unarchivedRecord = CKRecord(coder: unarchiver) return unarchivedRecord } 

31:10 WWDC 2015 - Session 715 - iOS, OS X