CWnd::get_accFocus
Visual Studio 2010
Called by the framework to retrieve the object that has the keyboard focus.
virtual HRESULT get_accFocus( VARIANT *pvarChild );
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::get_accFocus in the Windows SDK.