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unit API.Generics; interface uses System.Classes // , System.Generics.Collections , System.Generics.Defaults ; type TSort = (sNone, sAsc, sDes); TDynamicObjectList<T: class> = class(TObjectList<T>) private fComparer: TComparison<T>; fSortField: string; fSort: TSort; function CompareNumbers(const L, R: Integer): Integer; function CompareObjects(const aLeft, aRight: T): Integer; public constructor CreateWithSort(const aSortField: string; aSort: TSort = sAsc); procedure Sort(aSort: TSort = sAsc); function IsSortedCorrectly: Boolean; end; implementation uses System.SysUtils , System.Rtti , System.TypInfo ; { TDynamicObjectList<T> } constructor TDynamicObjectList<T>.CreateWithSort(const aSortField: string; aSort: TSort); begin inherited Create(True); fSortField := aSortField; fSort := aSort; fComparer := CompareObjects; end; function TDynamicObjectList<T>.CompareNumbers(const L, R: Integer): Integer; begin Result := L - R; end; function TDynamicObjectList<T>.CompareObjects(const aLeft, aRight: T): Integer; var L_Ctx : TRttiContext; L_Typ : TRttiType; L_Prop : TRttiProperty; L_Left : TClass absolute aLeft; L_Right : TClass absolute aRight; L_LeftValue, L_RightValue: TValue; begin if fSortField = '' then begin // Use default comparer if no specific field is specified .. Result := TComparer<T>.Default.Compare(T(L_Left), T(L_Right)); Exit; end; L_Ctx := TRttiContext.Create; try L_Typ := L_Ctx.GetType(T); // Get RTTI for type ( T ) L_Prop := nil; L_Prop := L_Typ.GetProperty(fSortField); if Assigned(L_Prop) then begin L_LeftValue := L_Prop.GetValue(L_Left); L_RightValue := L_Prop.GetValue(L_Right); case L_LeftValue.Kind of tkInteger, tkInt64: case fSort of sAsc: Result := CompareNumbers(L_LeftValue.AsInteger, L_RightValue.AsInteger); sDes: Result := CompareNumbers(L_RightValue.AsInteger, L_LeftValue.AsInteger); else Result := TComparer<T>.Default.Compare(T(L_Left), T(L_Right)); end; tkString, tkWString, tkLString, tkUString: case fSort of sAsc: Result := CompareNumbers(Integer.Parse(L_LeftValue.AsString), Integer.Parse(L_RightValue.AsString)); sDes: Result := CompareNumbers(Integer.Parse(L_LeftValue.AsString), Integer.Parse(L_RightValue.AsString)); else Result := TComparer<T>.Default.Compare(T(L_Left), T(L_Right)); end; else TComparer<T>.Default.Compare(T(L_Left), T(L_Right)); end; end else Result := 0; // Handle case where property is not found finally L_Ctx.Free; end; end; function TDynamicObjectList<T>.IsSortedCorrectly: Boolean; var I: Integer; begin Result := True; for I := 1 to Count - 1 do begin if CompareObjects(Items[I - 1], Items[I]) > 0 then begin Result := False; Break; end; end; end; procedure TDynamicObjectList<T>.Sort(aSort: TSort); begin fSort := aSort; inherited Sort(TComparer<T>.Construct(fComparer)); end; end. using: in separate Unit: MyFonts.pas type TFonType = (ft_TTF, ft_OTF, ft_Unknown); TFontInfo = class strict private fFileID, fFontName : string; fFontType : TFonType; fFontFileName: string; private function Get_FontType: string; procedure Set_FontType(const aValue: string); public constructor Add(const aFileID, aFontName: string; const aFontType: TFonType); destructor Destroy; override; property ID: string read fFileID write fFileID; property FontName:string read fFontName write fFontName; property FontType:string read Get_FontType write Set_FontType; property FontFileName: string read fFontFileName write fFontFileName; end; TFontsList = class(TDynamicObjectList<TFontInfo>); in MainForm: uses MyFonts; procedure TMainView.FormCreate(Sender: TObject); var L_FontInfo: TFontInfo; L_ListItem: TListItem; begin fFontsRes_List := TFontsList.CreateWithSort('ID'); // Add some sample data fFontsLst.Add(TFontInfo.Add('3', 'Courier New', ft_TTF)); fFontsLst.Add(TFontInfo.Add('1', 'Arial', ft_TTF)); fFontsLst.Add(TFontInfo.Add('2', 'Times New Roman', ft_OTF)); // Sort the list by ID in Asc fFontsLst.Sort(sAsc); // Populate the ListView for L_FontInfo in fFontsLst do begin L_ListItem := LV_Fonts.Items.Add; L_ListItem.Caption := L_FontInfo.ID; L_ListItem.SubItems.Add(L_FontInfo.FontName); L_ListItem.SubItems.Add(L_FontInfo.FontType); L_ListItem.SubItems.Add(L_FontInfo.FontFileName); end; end; procedure TMainView.FormDestroy(Sender: TObject); begin fFontsRes_List.Free; end; currentlly it's works only with fields marked as string or integer but real value are in integer and sorted using : CompareNumbers