delphiコンポーネントのプロパティ：TObjectList <TPicture>

Question

プロパティとしてサイズの異なる複数のTImageを挿入できるVCLコンポーネントを作成しようとしています。 私はTObjectList（Delphi component with a variable amount of TPictures）を一番よく使うように言われましたが、今は、プロパティエディタで単一のTPi​​cturesをに割り当てることに苦労しています。

私は現時点で持っているもの：どのような動作しないことのPropertyEditorで最終的な結果である

unit ImageMultiStates; 

interface 

uses 
    Vcl.Graphics, Vcl.StdCtrls, System.SysUtils, System.Classes, Vcl.Controls, Vcl.ExtCtrls, Forms, Generics.Collections; 

type 

    TImageMultiStates = class(TImage) 
    private 
    FPictures: TObjectList<TPicture>; 
    procedure SetPicture(Which: Integer; APicture: TPicture); 
    function GetPicture(Which: Integer): TPicture; 
    public 
    Count: integer; 
    constructor Create(AOwner: TComponent); override; 
    destructor Destroy; override; 
    procedure Activate(Which: Integer); 
    published 
    // property Pictures: TObjectList<TPicture> read GetPicture write SetPicture; 
    // property Pictures[Index: Integer]: TObjectList<TPicture> read GetPicture write SetPicture; 
    property Pictures: TObjectList<TPicture> read FPictures write FPictures; 
    end; 

procedure Register; 

implementation 

constructor TImageMultiStates.Create(AOwner: TComponent); 
begin 
    inherited Create(AOwner); 
    FPictures := TObjectList<TPicture>.Create; 
end; 

destructor TImageMultiStates.Destroy; 
begin 
    FPictures.Free; 
    inherited Destroy; 
end; 

procedure TImageMultiStates.SetPicture(Which: Integer; APicture: TPicture); 
begin 
    FPictures[Which] := APicture; 
    if Which=0 then 
    Picture.Assign(APicture); 
end; 

function TImageMultiStates.GetPicture(Which: Integer): TPicture; 
begin 
    Result := FPictures[Which]; 
end; 

procedure TImageMultiStates.Activate(Which: Integer); 
begin 
    Picture.Assign(FPictures[Which]); 
end; 

procedure Register; 
begin 
    RegisterComponents('Standard', [TImageMultiStates]); 
end; 

end. 

（それがコンパイルされます）。値 "（TObjectList）"を持つ "Pictures"という1つの項目が表示されます。それをクリックすると何もしない、私は適切なエディタを取得しません。 最初のものはコンパイラエラー "E2008 Incompatible Types"をスローし、もう1つは "Publishedプロパティ 'Pi​​ctures'をタイプARRAYにすることはできません。

Answer 1

IDEは設計時にTObjectListを編集する方法を知らず、DFMストリーミングシステムはTObjectListをストリームする方法を知らない。カスタムプロパティエディタとカスタムストリーミングロジックを実装する必要があります。それは確かに可能ですが、それは多くの仕事です。

あなたがしようとしているのは、代わりにSystem.Classes.TCollectionを使用してください。 IDEおよびDFMストリーミングシステムには、TCollectionを自動的に処理してストリーミングするためのビルトインサポートが組み込まれています。私はあなたがパブリッシュプロパティ（私はところで、いずれか、することはできませんわからない）としてジェネリックを使用することができるかわからない

unit ImageMultiStates; 

interface 

uses 
    System.Classes, Vcl.Controls, Vcl.ExtCtrls, Vcl.Graphics; 

type 
    TImagePictureItem = class(TCollectionItem) 
    private 
    FPicture: TPicture; 
    procedure PictureChanged(Sender: TObject); 
    procedure SetPicture(Value: TPicture); 
    public 
    constructor Create(Collection: TCollection); override; 
    destructor Destroy; override; 
    published 
    property Picture: TPicture read FPicture write SetPicture; 
    end; 

    TImagePictureEvent = procedure(Sender: TObject; Index: Integer) of object; 

    TImagePictures = class(TOwnedCollection) 
    private 
    FOnPictureChange: TImagePictureEvent; 
    function GetPicture(Index: Integer): TImagePictureItem; 
    procedure SetPicture(Index: Integer; Value: TImagePictureItem); 
    protected 
    procedure Update(Item: TCollectionItem); override; 
    public 
    constructor Create(Owner: TComponent); reintroduce; 
    property Pictures[Index: Integer]: TImagePictureItem read GetPicture write SetPicture; default; 
    property OnPictureChange: TImagePictureEvent read FOnPictureChange write FOnPictureChange; 
    end; 

    TImageMultiStates = class(TImage) 
    private 
    FActivePicture: Integer; 
    FPictures: TImagePictures; 
    function GetPicture(Index: Integer): TPicture; 
    procedure PictureChanged(Sender: TObject; Index: Integer); 
    procedure SetActivePicture(Index: Integer); 
    procedure SetPicture(Index: Integer; Value: TPicture); 
    procedure SetPictures(Value: TImagePictures); 
    protected 
    procedure Loaded; override; 
    public 
    constructor Create(Owner: TComponent); override; 
    function Count: integer; 
    property Pictures[Index: Integer]: TPicture read GetPicture write SetPicture; 
    published 
    property ActivePicture: Integer read FActivePicture write SetActivePicture default -1; 
    property Picture stored False; 
    property Pictures: TImagePictures read FPictures write SetPictures; 
    end; 

procedure Register; 

implementation 

{ TImagePictureItem } 

constructor TImagePictureItem.Create(Collection: TCollection); 
begin 
    inherited Create(Collection); 
    FPicture := TPicture.Create; 
    FPicture.OnChange := PictureChanged; 
end; 

destructor TImagePictureItem.Destroy; 
begin 
    FPicture.Free; 
    inherited; 
end; 

procedure TImagePictureItem.PictureChanged(Sender: TObject); 
begin 
    Changed(False); 
end; 

procedure TImagePictureItem.SetPicture(Value: TPicture); 
begin 
    FPicture.Assign(Value); 
end; 

{ TImagePictures } 

constructor TImagePictures.Create(Owner: TComponent); 
begin 
    inherited Create(Owner, TImagePictureItem); 
end; 

function TImagePictures.GetPicture(Index: Integer): TImagePictureItem; 
begin 
    Result := TImagePictureItem(inherited GetItem(Index)); 
end; 

procedure TImagePictures.SetPicture(Index: Integer; Value: TImagePictureItem); 
begin 
    inherited SetItem(Index, Value); 
end; 

procedure TImagePictures.Update(Item: TCollectionItem); 
begin 
    if Assigned(FOnPictureChange) then 
    begin 
    if Item <> nil then 
     FOnPictureChange(Self, Item.Index) 
    else 
     FOnPictureChange(Self, -1); 
    end; 
end; 

{ TImageMultiStates } 

constructor TImageMultiStates.Create(Owner: TComponent); 
begin 
    inherited Create(Owner); 
    FPictures := TImagePictures.Create(Self); 
    FPictures.OnPictureChange := PictureChanged; 
    FActivePicture := -1; 
end; 

procedure TImageMultiStates.Loaded; 
begin 
    inherited; 
    PictureChanged(nil, FActivePicture); 
end; 

function TImageMultiStates.Count: Integer; 
begin 
    Result := FPictures.Count; 
end; 

procedure TImageMultiStates.PictureChanged(Sender: TObject; Index: Integer); 
begin 
    if (FActivePicture <> -1) and ((Index = -1) or (Index = FActivePicture)) then 
    Picture.Assign(GetPicture(FActivePicture)); 
end; 

function TImageMultiStates.GetPicture(Index: Integer): TPicture; 
begin 
    Result := FPictures[Index].Picture; 
end; 

procedure TImageMultiStates.SetPicture(Index: Integer; Value: TPicture); 
begin 
    FPictures[Index].Picture.Assign(Value); 
end; 

procedure TImageMultiStates.SetActivatePicture(Value: Integer); 
begin 
    if FActivePicture <> Value then 
    begin 
    if ComponentState * [csLoading, csReading] = [] then 
     Picture.Assign(GetPicture(Value)); 
    FActivePicture := Value; 
    end; 
end; 

procedure Register; 
begin 
    RegisterComponents('Standard', [TImageMultiStates]); 

    // the inherited TImage.Picture property is published, and you cannot 
    // decrease the visibility of an existing property. However, if you move 
    // this procedure into a separate design-time package, you can then use 
    // DesignIntf.UnlistPublishedProperty() to hide the inherited 
    // Picture property at design-time, at least: 
    // 
    // UnlistPublishedProperty(TImageMultiStates, 'Picture'); 
    // 
    // Thus, users are forced to use the TImageMultiStates.Pictures and 
    // TImageMultiStates.ActivePicture at design-time. The inherited 
    // Picture property will still be accessible in code at runtime, though... 
end; 

end.