+2  A: 

What you generally use in these cases is called the Facade Pattern. In your case, you'd build a wrapper for the functions of the game center you use in your app, and then two implementations -- one which probably does little more than proxy calls to the game center and another which returns canned answers as required.

I will note that I've never done any iOS/objective C programming so I have no idea how one would actually implement this properly in that environment.

Wyatt Barnett  2010-10-22 18:14:46
You would implement it exactly as you describe :) more specifically, have a wrapper class/object that all gamecenter calls go through. The class checks if the APIs are actually available, and responds appropriately, and the rest of the app can be agnostic to Game Center detection. If the gamecenter API later changes, only need to change it in one place in the app.
Jaanus  2010-10-22 18:17:20
That sounds like a very elegant solution, thank you!
BeachRunnerJoe  2010-10-22 18:28:37

related questions

Beyond GoF design patterns
What are some real life examples of Design Patterns used in software
What is a good online resource for css 'design patterns'?
In C#, isn't the observer pattern already implemented using Events?
A more generic visitor pattern
Is there a simple, elegant way to define Singletons in Python?
Where do I use delegates?
Using MVP - How to use Events Properly for Testing
Java Singleton vs static - is there a real performance benefit?
Abstract Factory Design Pattern
What is MVC and what are the advantages of it?
Beyond design patterns?
Best book/resource for learning Java design patterns?
What Are Some Examples of Design Pattern Implementations Using JavaScript?
Transactional Design Pattern
Can you really build a fast word processor with GoF Design Patterns?
Singletons: good design or a crutch?
File Parse Design Pattern
Do you use design patterns?
Do you know any patterns for GUI programming? (Not patterns on designing GUIs)
Unit of Work Pattern in .Net
What's your favourite way of interacting with DBs from your programming language?
Why all the Active Record hate?
What JavaScript patterns do you use most?
How do I create a Class using the Singleton Design Pattern in Ruby?