How do I set Cell to be false when slide scrollbars

[sun]

I set Cell.IsEnable to be false  ,like this:
 dataGrid1.RowLoaded += new EventHandler<RowLoadedEventArgs>(dataGrid1_RowLoaded);
 void dataGrid1_RowLoaded(object sender, RowLoadedEventArgs e)
        {
            e.Row.Cells[0].IsEnabled = false;
        }


But  it is not Cell which I need to be false when I slide   Horizontal scrollbars or Vertical scrollbars .

is it Bug?;  I have a picture about this question!