MoveRowAtIndexPath in UITableView causes incorrect animation

Question

I have a simple UITableView controller that shows CoreData. I am trying to implement - (void) tableView: (UITableView *) tableView moveRowAtIndexPath: (NSIndexPath *) fromIndexPath toIndexPath: (NSIndexPath *) toIndexPath; and there were problems with the animation. The Core Data Store is being updated, but the animation does not work.

How can I make the animation correctly reflect the changes that occur with the main data objects?

For instance:

Initial order:

After item 2 above:

or, initial order:

After moving element 1 to position 3:

Here is the relevant code:

- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath {
//this implementation is from this tutorial: http://www.cimgf.com/2010/06/05/re-ordering-nsfetchedresultscontroller/
NSMutableArray *things = [[fetchedResultsController fetchedObjects] mutableCopy];

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

// Remove the object we're moving from the array.
[things removeObject:thing];
// Now re-insert it at the destination.
[things insertObject:thing atIndex:[toIndexPath row]];

// All of the objects are now in their correct order. Update each
// object displayOrder field by iterating through the array.


int i = 0;
for (NSManagedObject *mo in things)
{
    [mo setValue:[NSNumber numberWithInt:i++] forKey:@"order"];
}


NSLog(@"things: %@", things);
[things release], things = nil; 

[managedObjectContext save:nil];            
}

and delegate:

- (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type newIndexPath:(NSIndexPath *)newIndexPath {
NSLog(@"didChangeObject:");
UITableView *tableView = self.tableView;

switch(type) {
    case NSFetchedResultsChangeInsert:
        NSLog(@"ResultsChangeInsert:");
        [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
        break;

    case NSFetchedResultsChangeDelete:
        [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
        break;

    case NSFetchedResultsChangeMove:
        [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
        [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
        break;
}
}

Answer 1

, . bool ManagedObjectContext:

= ;     [managedObjectContext save: nil];

, FetchedResultsController. , . /, , .

/**
Delegate methods of NSFetchedResultsController to respond to additions, removals and so  on.
*/

- (void)controllerWillChangeContent:(NSFetchedResultsController *)controller {

if (!reordering) {

// The fetch controller is about to start sending change notifications, so prepare the table view for updates.
NSLog(@"controllerWillChangeContent:");

[self.tableView beginUpdates];

}

}


- (void)controller:(NSFetchedResultsController *)controller didChangeObject:(id)anObject atIndexPath:(NSIndexPath *)indexPath forChangeType:(NSFetchedResultsChangeType)type newIndexPath:(NSIndexPath *)newIndexPath {
if (!reordering) {

    NSLog(@"didChangeObject:");
    UITableView *tableView = self.tableView;

    switch(type) {
        case NSFetchedResultsChangeInsert:
            NSLog(@"ResultsChangeInsert:");
            [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;

        case NSFetchedResultsChangeDelete:
            [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;

        /*case NSFetchedResultsChangeMove:
            [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
            [tableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndexPath] withRowAnimation:UITableViewRowAnimationFade];
            break;*/
    }

}
}

- (void)controller:(NSFetchedResultsController *)controller didChangeSection:(id <NSFetchedResultsSectionInfo>)sectionInfo atIndex:(NSUInteger)sectionIndex forChangeType:(NSFetchedResultsChangeType)type {
if (!reordering) {

    NSLog(@"didChangeSelection:");
    switch(type) {
        case NSFetchedResultsChangeInsert:
            [self.tableView insertSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade];
            break;

        case NSFetchedResultsChangeDelete:
            [self.tableView deleteSections:[NSIndexSet indexSetWithIndex:sectionIndex] withRowAnimation:UITableViewRowAnimationFade];
            break;
    }
}
}


- (void)controllerDidChangeContent:(NSFetchedResultsController *)controller {
if (!reordering) {

    NSLog(@"didChangeContent:");
    // The fetch controller has sent all current change notifications, so tell the table view to process all updates.
    [self.tableView endUpdates];
}else {
    reordering = NO;
}

}

Answer 2

, , . :.

- (void)setEditing:(BOOL)editing animated:(BOOL)animated
{
    [super setEditing:editing animated:animated];
    if (!editing) {
        //save here
    }
}

, , , . -(void)setEditing .

btw, , !