Core Data was mutated while being enumerated

Question

I\'ve an annoying problem with Core Data. My app need to get contacts from iPhone and save it in my database. I\'m trying to do that in background thread.

I

Answer 1

This error happen when you are modifying core data while you try to get them.

That also could be cause of the loop you're doing, you are inserting a new object in coredata without saving before you do an other retrieve. Try saving your managedobjectcontext :

favorite I have an annoying problem with Core Data. My app need to get contacts from iPhone and save it in my database. I'am trying to do that in background thread.

I use above code for that:

[self performSelectorInBackground:@selector(fetchingContact) withObject:nil];


-(void)fetchingContact{
// Some Code
for (int i = 0; i < nPeople; i++)
{
//Some Code
    NSManagedObjectContext *context = [APP_DELEGATE managedObjectContext];
    ABRecordID recordID = ABRecordGetRecordID(person);
    NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Contact" inManagedObjectContext:context];
    [fetchRequest setEntity:entity];
    NSPredicate *predicate = [NSPredicate predicateWithFormat:[NSString stringWithFormat:@"(contactId = '%d')",recordID]];
    [fetchRequest setPredicate:predicate];
    NSError *error = nil;
    NSArray *contactObjArray = [context executeFetchRequest:fetchRequest error:&error];
    if (error) {}
    Contact *contacts;
    if (contactObjArray.count == 0) {
        contacts = [NSEntityDescription insertNewObjectForEntityForName:@"Contact" inManagedObjectContext:context];
        [context save:&error];
    }else {
        contacts = [contactObjArray objectAtIndex:0];
    }
//Some Code
}
}

If that doesn't solve your problem, maybe check if your method is called multiple times.