I'm looking for an approach to the following problem:
I have a reusable library. It contains a controller class, in the MVC sense. Let's say it's called
UserAdministrationController, and it's for editing users. This class requires an object implementing
IUserStorage, for storing its data. The library doesn't need to know the details of how this object works.
Now I want to write an application that includes the library. In it, I'll provide an implementation of
IUserStorage. To instantiate this, I'll need to pass it some dependencies, like a database object, and other things that my application only knows about at runtime.
But how would I then pass this object from my application to the library? I'm not instantiating the
UserAdministrationController directly from my application; it gets created by the library itself.
Hope this makes sense. I'm trying to keep my description abstract and not specific to a particular framework or language.