private void OnChange(IRealmCollection <T> sender, ChangeSet change, Exception error)
{
if (error != null)
{
Realm.NotifyError(error);
}
else if (change != null)
{
if (change.Moves.Length > 0 &&
change.Moves.Length == change.InsertedIndices.Length &&
change.Moves.Length == change.DeletedIndices.Length)
{
var ordered = change.Moves.OrderBy(m => m.From);
var movedPositions = -1;
var isConsecutiveMove = true;
foreach (var item in ordered)
{
if (movedPositions == -1)
{
movedPositions = item.To - item.From;
}
else if (item.To - item.From != movedPositions)
{
isConsecutiveMove = false;
break;
}
}
if (isConsecutiveMove)
{
var initialItem = ordered.First();
var movedItems = Enumerable.Range(initialItem.To, change.Moves.Length)
.Select(i => sender[i])
.ToList();
RaiseCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Move, movedItems, initialItem.To, initialItem.From));
}
else
{
RaiseCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
}
RaisePropertyChanged();
return;
}
var raiseRemoved = TryGetConsecutive(change.DeletedIndices, _ => default(T), out var removedItems, out var removedStartIndex);
var raiseAdded = TryGetConsecutive(change.InsertedIndices, i => this[i], out var addedItems, out var addedStartIndex);
if (raiseAdded || raiseRemoved)
{
if ((raiseAdded && raiseRemoved) ||
(raiseAdded && addedItems == null) ||
(raiseRemoved && removedItems == null))
{
RaiseCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
RaisePropertyChanged();
return;
}
if (removedItems != null)
{
RaiseCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Remove, removedItems, removedStartIndex));
RaisePropertyChanged();
}
if (addedItems != null)
{
RaiseCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, addedItems, addedStartIndex));
RaisePropertyChanged();
}
}
}
}
