private
   TabS: array of TcxTabSheet;
   function GetCount : integer;

function Tfrm_Main.AddTabSheet: TcxTabSheet;
begin
 SetLength(TabS, GetCount + 1);
//  TabS[GetCount-1] := TcxTabSheet.Create(nil);
 TabS[GetCount-1] := TcxTabSheet.Create(pc_MainPages);
 TabS[GetCount-1].PageControl := pc_MainPages;
 Result := TabS[GetCount-1];
end;

procedure Tfrm_Main.MainTreeClick(Sender: TObject);
begin
 if DM.T_MTree.FieldByName('ID_PARENT').AsInteger > 0 then
   begin
     if not SearchSameTabs(DM.T_MTree.FieldByName('TAG').AsInteger, TSheetIndex) then
       begin
         pc_MainPages.Visible := true;
         AddTabSheet;  
         TabS[GetCount-1].Caption := ClickNode.Text + ' (' + DM.T_MTree.FieldByName('TAG').AsString + ')';
         TabS[GetCount-1].Tag := DM.T_MTree.FieldByName('TAG').AsInteger;
         TabS[GetCount-1].Name := 'TabSheet_' + DM.T_MTree.FieldByName('TAG').AsString;
//          TabS[GetCount-1].OnResize := TabSheetResize;

         pc_MainPages.ActivePageIndex := GetCount-1;
       end
     else
       pc_MainPages.ActivePageIndex := TSheetIndex;
   end;

 case DM.T_MTree.FieldByName('TAG').AsInteger of
   301: begin
          if frm_Employees = nil then
            frm_Employees := Tfrm_Employees.Create(nil);
            with frm_Employees do
              begin
                Parent := FindComponent('TabSheet_301') as TcxTabSheet;
                Left := 0;
                Top := 0;
                Show;
              end;
        end;
 end;
end;