Refreshing listview item count

I have a listview with checkboxes. When i click on a row but not checkboxes the row data is copied for updating in appropriate textboxes.

But when i click on checkboxes the row data is not copied. If only one time by mistake i click on a row then after even if i click on checkboxes the program enters in update mode and whole row data is copied.

Because the control is done with rapview.SelectedItems.Count which remains 1

 if (rapview.SelectedItems.Count == 0)
      return;

Is it possible to set to zero SelectedItems.Count to ZERO without recalling the query ?