Up to this point in the book we've been primarily working off the main example of the Crystal Game. Now, we depart from the Crystal Game example for the sake of further illustration. This chapter and the next provide small case studies showing how the Theme approach can be applied in different situations. In this chapter, we look at a set of simple phone features and their composition. This is a scaled-down version of what you would find in the real world. Of course, telephony systems have many interacting features; here we have limited the number of interactions between features so that we can comprehensively describe the case study system. We've also chosen to focus not on features related to call-handling (like call waiting, call forwarding, etc.), but on broader features, specifically, voice call, short messaging service (SMS), a media player, and a game application, all provided on a mobile phone handset. |