iPhone App Development: The Missing Manual

Technical Design: Between Pictures and Code

But for now, everyone on the team is happy with the design, so it's time to start building it. Oh boy, you finally get to write some code! But not just yet.

The final step in the iPhone app design process is to translate the visual design into a technical design. You're going to be creating classes with methods as you work toward what you've put on paper. It's a good idea to think about how these pieces are going to fit together in the Model-View-Controller (MVC) pattern that was mentioned in the previous chapter.

If you neglect this important step, you'll find that you end up rewriting a lot of code. You don't need to write a 100-page specification that describes the technical needs in minute detail, but you do need to spend a little time planning where you're headed.

Start Naming

A good first step in this process is to start giving things names. You've probably already come up with some terminology as you've discussed the design with the other members of your team. It's time to start codifying the pieces of your application.

A UIViewController typically manages a screenful of data in an iPhone app. Since you're going to have two screens in your product, that's a natural place to start naming things. The view with the light source is the first one that you see after launch, so you decide to call it the "main screen." It would be fun to call the other view the "dimmer switch screen," but you think better of it and call it the "settings screen." ...