This is a useful base class for creating a class factory that you can then register with the factory registry.
The following is an excerpt from the LocationPage.h file in the sample project to define the ClassFactoryImpl class.
class LocationPageFactory : publicClassFactoryImpl
The following is an excerpt from the LocationPage.cpp file in the sample wizard page used to define the class factory for the page.
return static_cast<IWizardPage *>(new LocationPage);