private void ProcessCollectionChanged(NotifyCollectionChangedEventArgs args)
{
if (this.CheckFlag(CollectionViewFlags.ShouldProcessCollectionChanged))
{
if (args.get_Action() == 4)
{
if (!this.SourceCollection.GetEnumerator().MoveNext())
{
this._internalList.Clear();
}
this.RefreshOrDefer();
}
else
{
object item = (args.get_NewItems() != null) ? args.get_NewItems()[0] : null;
object removedItem = (args.get_OldItems() != null) ? args.get_OldItems()[0] : null;
if ((args.get_Action() == 1) || (args.get_Action() == 2))
{
this.ProcessRemoveEvent(removedItem, args.get_Action() == 2);
}
if (((args.get_Action() == null) || (args.get_Action() == 2)) && ((this.Filter == null) || this.PassesFilter(item)))
{
this.ProcessAddEvent(item, args.get_NewStartingIndex());
}
if (args.get_Action() != 2)
{
this.OnPropertyChanged("ItemCount");
}
}
}
}
