How to increase the column width of the rowheader in WinForms GridGroupingControl?

//Increases the ColWidth of the NumberedRowHeader.this.gridGroupingControl1.TableModel.QueryColWidth += TableModel_QueryColWidth;
void TableModel_QueryColWidth(object sender, GridRowColSizeEventArgs e) 
{   
if(e.Index ==0)
{
     //Increases the RowHeader width based on digit count.
     e.Size = 30;
     e.Handled = true;
   }}

'Increases the ColWidth of the NumberedRowHeader.
Private Me.gridGroupingControl1.TableModel.QueryColWidth += AddressOf TableModel_QueryColWidth
Private Sub TableModel_QueryColWidth(ByVal sender As Object, ByVal e As GridRowColSizeEventArgs)
  If e.Index =0 Then
     'Increases the RowHeader width based on digit count.
     e.Size = 30
     e.Handled = True
  End If
End Sub