private void Source2CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
if (e.Action == NotifyCollectionChangedAction.Move)
{
return;
}
if (e.Action == NotifyCollectionChangedAction.Reset)
{
var filtered = new List <TSource>(SL.Intersect(sourceItems.Keys, source));
sourceItems.Clear();
OnAddItems(filtered);
}
if (e.OldItems != null)
{
var removed = new HashSet <TSource>(sourceItems.Comparer);
foreach (TSource item in e.OldItems)
{
if (RemoveItem(item))
{
removed.Add(item);
}
}
var changed = SL.Where(source, item => removed.Contains(item));
OnAddItems(changed);
}
if (e.NewItems != null)
{
var added = new HashSet <TSource>(sourceItems.Comparer);
foreach (TSource item in e.NewItems)
{
if (AddItem(item))
{
added.Add(item);
}
}
var changed = SL.Where(source, item => added.Contains(item));
OnRemoveItems(changed);
}
}