method private _cb__down_button_clicked = fun () ->
    match view2.st_view#selection#get_selected_rows with
      | [path] ->
          let path_next = GTree.Path.copy path in
            GTree.Path.next path_next;
            if path_is_valid store2 path_next then
              let row  = store2#get_row_reference path
              and row' = store2#get_row_reference path_next in
                i_bool (store2#swap row#iter row'#iter);
                connect#raise_moved_down row row'
      | _ ->
          ()