anchor.diff:      procedure   SetSortPages(const AValue: boolean);
       procedure   SetStyle(const AValue: TfpgTabStyle);
       procedure   SetTabPosition(const AValue: TfpgTabPosition);
  -    procedure   DoChange(ATabSheet: TfpgTabSheet);
  +    procedure   DoPageChange(ATabSheet: TfpgTabSheet);
       function    DrawTab(const rect: TfpgRect; const Selected: Boolean = False; const Mode: Integer = 1): TfpgRect;
     protected
       procedure   OrderSheets; // currently using bubblesort
  
positive.code:            if h <> ActivePage then
             begin
                ActivePage := h;
                DoChange(ActivePage);
             end;
             exit;
          end;  { if }
  
negative.code:   if AValue <> nil then
      FActivePageIndex := FPages.IndexOf(AValue);
    RePaint;
    DoPageChange(FActivePage);
  end;
  
  function TfpgPageControl.MaxButtonWidthSum: integer;
  