Appologies for the vagueness, in my attempt to generalize the question and related concepts..
The child class is FiniteStateMachine found here http://www.arduino.cc/playground/Code/FiniteStateMachine
The author was kind in answering my questions; he actually pointed out that the 'State' object in this class calls back to a general function.
As far as a very general description
on the use of the FiniteStateMachine goes, it governs the sensing of ONE PushButton switch. I've written a sketch using the FSM class as it stands, and I'm rather thrilled at how well it works !!
The FSM reports back things like Click, DoubleClick, ClickAndHold, DoubleClickAndHold, and ButtonUp. It's fast, and very few lines of code are required, thanks to the finite state machine concept. So, one FSM, governs the many states (3, declared in a sketch) of one button. The encapsulating class I am working on is to tie together the 3 states, FSM, and callback functions into a neat little package. Multiple instances of the resulting Parent class will be convenient to instantiate multiple buttons working in a similar way. These buttons will eventually govern a motorized astronomical telescope driven by stepper motors.
Question on a comment in your post:
Assuming one were to make the child (State) aware of a parent (the class I am now working on), could one make this a generic awareness? In other words, if I write a FAtherParent, MotherParent, or even a GrandParent class in the future, could the State class be used arbitrarily with any parent?
Thanks in advance!