无法覆盖TCollection.Notify:Notify声明与之前的声明不同

Pau*_*aul 2 delphi tcollection

注意:其他问题的标题不同,这使其无法识别为匹配的标题.

System.Classes

TCollection = class(TPersistent)
protected
  procedure Notify(Item: TCollectionItem; Action: TCollectionNotification); virtual;
end;
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MyUnit

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
  System.Classes,
  Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls,
  Vcl.ExtCtrls, DB, System.Generics.Collections;

TTextDisplayLineInfos = class(TCollection)
protected
  procedure Notify(Item: TCollectionItem; Action: TCollectionNotification); override; //Here "[dcc32 Error] MyUnit.pas(85): E2037 Declaration of 'Notify' differs from previous declaration"
end;

implementation

procedure TTextDisplayLineInfos.Notify(Item: TCollectionItem;
  Action: TCollectionNotification);
begin
  inherited; //Here "[dcc32 Error] MyUnit.pas(475): E2008 Incompatible types"
  //..............
end;
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Notify方法的签名是通过复制粘贴进行的,因此不会出现任何错误;

错误

在界面部分:

[dcc32错误] MyUnit.pas(85):E2037"通知"声明与之前的声明不同

在实施部分:

[dcc32错误] MyUnit.pas(475):E2008不兼容的类型

Wai错了?

Uwe*_*abe 10

不幸的是,Delphi声明了TCollectionNotification两次:一个驻留在System.Classes中,另一个驻留在System.Generics.Collections中.

要解决此问题,请在uses子句中的System.Classes之前移动System.Generics.Collections,或将其限定为).System.Classes.TCollectionNotification