private void RemoveFromView(int itemIndex, object item)
{
_view.RemoveAt(itemIndex);
if (itemIndex <= CurrentPosition)
{
CurrentPosition--;
}
VectorChangedEventArgs e = new VectorChangedEventArgs(CollectionChange.ItemRemoved, itemIndex, item);
OnVectorChanged(e);
}
private bool HandleItemAdded(int newStartingIndex, object newItem, int?viewIndex = null)
{
if (_filter != null && !_filter(newItem))
{
return(false);
}
int newViewIndex = _view.Count;
if (_sortDescriptions.Any())
{
_sortProperties.Clear();
newViewIndex = _view.BinarySearch(newItem, this);
if (newViewIndex < 0)
{
newViewIndex = ~newViewIndex;
}
}
else if (_filter != null)
{
if (_source is null)
{
HandleSourceChanged();
return(false);
}
if (newStartingIndex == 0 || _view.Count == 0)
{
newViewIndex = 0;
}
else if (newStartingIndex == _source.Count - 1)
{
newViewIndex = _view.Count - 1;
}
else if (viewIndex.HasValue)
{
newViewIndex = viewIndex.Value;
}
else
{
for (int i = 0, j = 0; i < _source.Count; i++)
{
if (i == newStartingIndex)
{
newViewIndex = j;
break;
}
if (_view[j] == _source[i])
{
j++;
}
}
}
}
_view.Insert(newViewIndex, newItem);
if (newViewIndex <= CurrentPosition)
{
CurrentPosition++;
}
VectorChangedEventArgs e = new VectorChangedEventArgs(CollectionChange.ItemInserted, newViewIndex, newItem);
OnVectorChanged(e);
return(true);
}