CWnd::accNavigate
Visual Studio 2010
Called by the framework to traverse to another user interface element within a container and if possible, retrieve the object.
virtual HRESULT accNavigate( long navDir, VARIANT varStart, VARIANT *pvarEndUpAt );
This function is part of MFC's Active Accessibility support.
Override this function in your CWnd-derived class if you have nonwindowed user interface elements (other than windowless ActiveX controls, which MFC handles).
For more information, see IAccessible::accNavigate in the Windows SDK.