sajty/ember — comment on commit bdf80d1bece1cc5512eebeb41a6e962b5c3b2557
File: src/services/input/Input.h line 44
By erikhjortsberg:

If you want I can provide an example of how you could do this with an interface (like IWindowProvider).

I.e. so you'll do
attach(IWindowProvider* windowProvider, OIS::ParamList& params = OIS::ParamList());

The same interface could also be used for the isApplicationVisible method.