Delphi Language Guide Delphi for Microsoft Win32 Delphi for the Microsoft. Net framework

Changing Inherited Implementations
Descendant classes can change the way a specific interface method is implemented by overriding the implementing
method. This requires that the implementing method be virtual or dynamic.
A class can also reimplement an entire interface that it inherits from an ancestor class. This involves relisting the
interface in the descendant class' declaration. For example,
type
    IWindow = interface
    ['{00000115-0000-0000-C000-000000000146}']
    procedure Draw;
    .
    .
    .
end;
    TWindow = class(TInterfacedObject, IWindow)// TWindow implements IWindow
196

---

    procedure Draw;
    .
    .
    .
end;
TFrameWindow = class(TWindow, IWindow)// TFrameWindow reimplements IWindow
    procedure Draw;
    .
    .
    .
end;
Reimplementing an interface hides the inherited implementation of the same interface. Hence method resolution
clauses in an ancestor class have no effect on the reimplemented interface.