自定义类的数组作为属性

我试图使用自定义类的数组作为我的组件的属性,但问题是值没有保存到组件,这意味着如果我设置值,保存所有内容并再次打开项目,组件的值消失…我的代码如下所示：

unit Unit1;

interface

uses  Windows,ExtCtrls,Classes,Controls;

type

  TMyClass=class(TPersistent)
  private
    FName: string;
    FValue: double;
  public
    property Name: string read FName write FName;
    property Value: double read FValue write FValue;
  end;

  TMyComponent= class(TCustomPanel)
  private
    FMyArray: array[0..200] of TMyClass;

    function GetmyArray(Index: Integer): TMyClass;

    procedure SetMyArray(index: Integer; Value: TMyClass);
  public
    property myArray[index: Integer]: TMyClass read GetMyArray write SetMyArray;
  end;

implementation

function TMyComponent.GetmyArray(Index: Integer): TMyClass;
begin
  result:= FmyArray[Index];
end;

procedure TMyComponent.SetMyArray(index: Integer; Value: TMyClass);
begin
  FMyArray[index].FName:= Value.FName;
  FMyArray[index].FValue:= Value.FValue;
end;

end.

我知道只有已发布的属性可以流式传输,但问题是我的属性是一个数组而且无法发布…
我的建议是使用DefineProperties()来提供自定义流,但我不知道如何使用数组执行此操作.
我认为的其他可能性是将TMyClass修改为TMyComponent可以作为它的父类的类,就像它在TChart中完成的那样,你可以为它添加不同类的系列.但我不知道这应该是什么课

TMyClass=class(T???????????)

有了它,我可以取出属性MyArray并创建TMyClass并添加到TMyComponent如下：

MyArray1.parent:= MyComponent1;
MyArray2.parent:= MyComponent2;
...

.哪一个是更好的选择？或者还有其他更好的主意吗？

解决方法

最简单(和首选)的解决方案是将TMyClass更改为从TCollectionItem派生并将TMyComponent.FMyArray更改为TOwnedCollection.然后DFM将自动为您流式传输项目,您可以获得本机设计时支持,以创建和操作TMyClass对象及其属性.

试试这个：

unit Unit1;

interface

uses
  Windows,Controls;

type
  TMyClass = class(TCollectionItem)
  private
    FName: string;
    FValue: double;

    procedure SetName(const AValue: string);
    procedure SetValue(AValue: double);
  public
    procedure Assign(ASource: TPersistent); override;
  published
    property Name: string read FName write SetName;
    property Value: double read FValue write SetValue;
  end;

  TMyArray = class(TOwnedCollection)
  private
    function  GetItem(Index: Integer): TMyClass;
    procedure SetItem(Index: Integer; const Value: TMyClass);
  public
    constructor Create(AOwner: TPersistent);
    function  Add: TMyClass; reintroduce;
    function  Insert(Index: Integer): TMyClass; reintroduce;
    property  Items[Index: Integer]: TMyClass read GetItem write SetItem; default;
  end;

  TMyComponent = class(TCustomPanel)
  private
    FMyArray: TMyArray;

    procedure SetMyArray(Value: TMyArray);
  public
    constructor Create(AOwner: TComponent); override;
    destructor Destroy; override;
  published
    property myArray: TMyArray read FMyArray write SetMyArray;
  end;

implementation

procedure TMyClass.Assign(ASource: TPersistent);
begin
  if ASource is TMyClass then
  begin
    with TMyClass(ASource) do
    begin
      Self.FName := Name;
      Self.FValue := Value;
    end;
    Changed(False);
  end else
    inherited;
end;

procedure TMyClass.SetName(const AValue: string);
begin
  if FName <> AValue then
  begin
    FName := AValue;
    Changed(False);
  end;
end;

procedure TMyClass.SetValue(AValue: double);
begin
  if FValue <> AValue then
  begin
    FValue := AValue;
    Changed(False);
  end;
end;

constructor TMyArray.Create(AOwner: TPersistent);
begin
  inherited Create(AOwner,TMyClass);
end;

function TMyArray.GetItem(Index: Integer): TMyClass;
begin
  Result := TMyClass(inherited GetItem(Index));
end;

procedure TMyArray.SetItem(Index: Integer; const Value: TMyClass);
begin
  inherited SetItem(Index,Value);
end;

function TMyArray.Add: TMyClass;
begin
  Result := TMyClass(inherited Add);
end;

function TMyArray.Insert(Index: Integer): TMyClass;
begin
  Result := TMyClass(inherited Insert(Index));
end;

constructor TMyComponent.Create(AOwner: TComponent);
begin
  inherited;
  FMyArray := TMyArray.Create(Self);
end;

destructor TMyComponent.Destroy;
begin
  FMyArray.Free;
  inherited;
end;

procedure TMyComponent.SetMyArray(Value: TMyArray);
begin
  FMyArray.Assign(Value);
end;

end.