Modify data with CloudKit

Question

I have data I'd like to modify in CloudKit. I've found this question (Saving Modified Data in CloudKit) and it points to CKModifyRecordsOperation, but being new to this I'm looking for more guidance. I'm setting my object like so:

[object setValue:number forKey:@"total"];

If I'm only modifying one record and not all do I still call CKModifyRecordsOperation? Any clues to how this is done? I've been using [self.cloudManager saveRecord:object]; but with modifying the record this isn't working.

Answer 1

You can fetch, modify, and save changes you make to individual records.

The code snippet below shows how to fetch an Artwork record, changes the date attribute value, and saves it to the database.

// Fetch the record from the database
CKDatabase *publicDatabase = [[CKContainer containerWithIdentifier:containerIdentifier] publicCloudDatabase];
CKRecordID *artworkRecordID = [[CKRecordID alloc] initWithRecordName:@"115"];
[publicDatabase fetchRecordWithID:artworkRecordID completionHandler:^(CKRecord *artworkRecord, NSError *error) {
   if (error) {
      // Error handling for failed fetch from public database
   }
   else {
      // Modify the record and save it to the database
      NSDate *date = artworkRecord[@"date"];
      artworkRecord[@"date"]; = [date dateByAddingTimeInterval:30.0 * 60.0];
      [publicDatabase saveRecord:artworkRecord completionHandler:^(CKRecord *savedRecord, NSError *saveError) {
         // Error handling for failed save to public database
      }];
   }
}];

Consider to read this article for more detailed information.