Alternate contextWillSave

gistfile1.m

- (void)contextWillSave:(NSNotification *)notification
{
    NSManagedObjectContext *context = (NSManagedObjectContext *)notification.object;
    if (context.insertedObjects.count > 0) {
        NSArray *insertedObjects = [[context insertedObjects] allObjects];
        MRLog(@"Context %@ is about to save. Obtaining permanent IDs for new %lu inserted objects", [context MR_description], (unsigned long)[insertedObjects count]);
        __autoreleasing NSError *error = nil;
        BOOL success = [context obtainPermanentIDsForObjects:insertedObjects error:&error];
        if (!success && error) {
            [MagicalRecord handleErrors:error];
        }
    }
}