如何使用子属性编写属性？ [英] How do I code a property with sub-properties?

问题描述

例如，像Font。任何人都可以给出一个非常简单的例子吗？也许只是一个具有两个子属性的属性

---

编辑：我的意思是当我在对象检查器中查看Font有一点加号，我可以点击设置字体名称times new roman，字体大小10等。Sorrry如果我使用错误的术语，那就是我通过子属性。 >

解决方案

所有您需要做的是创建一个新的已发布属性，指向已发布属性的类型。

检查此代码

 键入
 TCustomType = class（TPersistent）//此类型有3个已发布的财产
 private 
 FColor：TColor; 
 FHeight：整数; 
宽度：整数; 
 public 
 procedure Assign（Source：TPersistent）;覆盖
发布
属性颜色：TColor读取FColor写入FColor; 
属性高度：整数读取FHeight写入FHeight; 
属性宽度：整数读宽度写FWidth; 
结束
 
 TMyControl = class（TWinControl）
 private 
 FMyProp：TCustomType; 
 FColor1：TColor; 
 FColor2：TColor; 
程序SetMyProp（AValue：TCustomType）; 
 public 
构造函数Create（AOwner：TComponent）;覆盖
析构函数覆盖
发布
属性MyProp：TCustomType读取FMyProp写SetMyProp; //现在这个属性有3个子属性（这个术语不存在于delphi中）
属性Color1：TColor读取FColor1写入FColor1; 
属性Color2：TColor读取FColor2写入FColor2; 
结束
 
 procedure TCustomType.Assign（Source：TPersistent）; 
 var 
 Src：TCustomType; 
 begin 
如果Source是TCustomType然后
 begin 
 Src：= TCustomType（Source）; 
 FColor：= Src.Color; 
身高：= Src.Height; 
 FWidth：= Src.Width; 
 end else 
继承; 
结束
 
构造函数TMyControl.Create（AOwner：TComponent）; 
开始
继承; 
 FMyProp：= TCustomType.Create; 
结束
 
析构函数TMyControl.Destroy; 
 begin 
 FMyProp.Free; 
继承; 
结束
 
程序TMyControl.SetMyProp（AValue：TCustomType）; 
 begin 
 FMyProp.Assign（AValue）; 
结束
  

For instance, like Font. Can anyone give a very simple example? Maybe just a property with two sub-properties

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Edit: I mean that when I look at Font in the object inspector it has a little plus sign which I can click to set font name "times new roman", font size "10", etc. Sorrry if I use the wrong terms, that is what I menat by "sub-properties".

解决方案

All you have to do is create a new published property that points to an type that has published properties.

check this code

  type
    TCustomType = class(TPersistent) //this type has 3 published properties
    private
      FColor : TColor;
      FHeight: Integer;
      FWidth : Integer;
    public
      procedure Assign(Source: TPersistent); override;
    published
      property Color: TColor read FColor write FColor;
      property Height: Integer read FHeight write FHeight;
      property Width : Integer read FWidth write FWidth;
    end;

    TMyControl = class(TWinControl) 
    private
      FMyProp : TCustomType;
      FColor1 : TColor;
      FColor2 : TColor;
      procedure SetMyProp(AValue: TCustomType);
    public
      constructor Create(AOwner: TComponent); override;
      destructor Destroy; override;
    published
      property MyProp : TCustomType read FMyProp write SetMyProp; //now this property has 3 "sub-properties" (this term does not exist in delphi)
      property Color1 : TColor read FColor1 write FColor1;
      property Color2 : TColor read FColor2 write FColor2;
    end;

  procedure TCustomType.Assign(Source: TPersistent);
  var
    Src: TCustomType;
  begin
    if Source is TCustomType then
    begin
      Src := TCustomType(Source);
      FColor := Src.Color;
      Height := Src.Height;
      FWidth := Src.Width;
    end else
      inherited;
  end;

  constructor TMyControl.Create(AOwner: TComponent);
  begin
    inherited;
    FMyProp := TCustomType.Create;
  end;

  destructor TMyControl.Destroy;
  begin
    FMyProp.Free;
    inherited;
  end;

  procedure TMyControl.SetMyProp(AValue: TCustomType);
  begin
    FMyProp.Assign(AValue);
  end;

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