private void SelectAllCells()
    {
      GridViewRowInfoEnumerator rowInfoEnumerator = new GridViewRowInfoEnumerator((IHierarchicalRow) this.GridViewElement.Template);
      List<GridViewCellInfo> gridViewCellInfoList = new List<GridViewCellInfo>();
      this.MasterTemplate.SelectedCells.BeginUpdate();
      this.MasterTemplate.SelectedCells.Clear();
      while (rowInfoEnumerator.MoveNext())
      {
        GridViewRowInfo current = rowInfoEnumerator.Current;
        if (current.CanBeSelected)
        {
          foreach (GridViewCellInfo cell in current.Cells)
            this.MasterTemplate.SelectedCells.Add(cell);
        }
      }
      this.MasterTemplate.SelectedCells.EndUpdate(true);
    }