Delphi Error – E2261 Implements clause only allowed for readable property

Delphi Compiler Error

E2261 Implements clause only allowed for readable property

Reason for the Error & Solution

The compiler has encountered a “write only” property that claims to implement an interface. A property must be read/write to use the implements clause.

program Produce;
type
  IMyInterface = interface
  end;

  TMyClass = class(TInterfacedObject, IMyInterface)
    FMyInterface: IMyInterface;
    property MyInterface: IMyInterface implements IMyInterface;
  end;
end.

The property in this example is write only and cannot be used to implement an interface.

program Solve;
type
  IMyInterface = interface
  end;

  TMyClass = class(TInterfacedObject, IMyInterface)
    FMyInterface: IMyInterface;
    property MyInterface: IMyInterface read FMyInterface implements IMyInterface;
  end;
end.

By adding a read clause, the property can use the implements clause.