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- (void)tableView:(UITableView *)tableView 
moveRowAtIndexPath:(NSIndexPath *)sourceIndexPath 
      toIndexPath:(NSIndexPath *)destinationIndexPath;
{ 
    NSMutableArray *things = [[fetchedResultsController fetchedObjects] mutableCopy];

    // Grab the item we're moving.
    NSManagedObject *thing = [[self fetchedResultsController] objectAtIndexPath:sourceIndexPath];

    // Remove the object we're moving from the array.
    [things removeObject:thing];

    // Now re-insert it at the destination.
    [things insertObject:thing atIndex:[destinationIndexPath row]];

    // All of the objects are now in their correct order. Update each
    // object's displayOrder field by iterating through the array.
    int i = 0;
    for (NSManagedObject *mo in things)
    {
        NSLog(@"%i - %@", i, [mo valueForKey:@"thingName"]);
        [mo setValue:[NSNumber numberWithInt:i++] forKey:@"displayOrder"];
    }
    [things release], things = nil;

    // Save
    if (![managedObjectContext save:&error]) 
    {
        NSString *msg = @"An error occurred when attempting to save your user profile changes.\nThe application needs to quit.";
        NSString *details = [NSString stringWithFormat:@"%@ %s: %@", [self class], _cmd, [error userInfo]];
        NSLog(@"%@\n\nDetails: %@", msg, details);
    }

    // re-do the fetch so that the underlying cache of objects will be sorted
    // correctly
    NSError *error = nil;
    if (![fetchedResultsController performFetch:&error])
    {
        NSLog(@"Unresolved error %@, %@", error, [error userInfo]);
        abort();
    }
}