wpf listcollectionview grouping by multiple columns and calculating the amount and quantity

ListCollectionView view = new ListCollectionView(lv.ItemsSource as IEnumerable);

if (view.GroupDescriptions != null)
{
    view.GroupDescriptions.Clear();
}
else
{
    view.GroupDescriptions = new ObservableCollection<GroupDescription>();
}

view.GroupDescriptions.Add(new PropertyGroupDescription("Location"));
view.GroupDescriptions.Add(new PropertyGroupDescription("Batch"));

for (int i = 0; i < view.Groups.Count; i++)
{
  Console.WriteLine("Amount: {0}", (view.Groups[i] as CollectionViewGroup).Items[0].GetType().GetProperty("Amount").GetValue((view.Groups[i] as CollectionViewGroup).Items[0]));
  Console.WriteLine("Quantity: {0}", (view.Groups[i] as CollectionViewGroup).Items[0].GetType().GetProperty("Quantity").GetValue((view.Groups[i] as CollectionViewGroup).Items[0]));