iPhone® Application Development All-In-One For Dummies®

Chapter 1. Understanding How an App Runs

In This Chapter

• Watching how the template-based app works at runtime

• Following what goes on when the user launches your app

• Getting a handle on how nib files work

• Remembering memory management

• Knowing what else you should be aware of at runtime

When you create an Xcode project and select a template, as shown in Chapter 4 of Book I, you get a considerable head start on the process of coding your very own iPhone app. Choosing the Utility Application template for the DeepThoughts app results in a working app that offers an information button to display the Flipside view, and a Done button on the Flipside view to get back to the main view.

As the wise sage (and wisecracking baseball player) Yogi Berra once said, "You can observe a lot just by watching." Before you add anything more to this skeleton of a utility app, it helps to look at how it does what it already does. By uncovering the mysteries of what this template does at runtime, you can learn a bit more about where to put your code.

As you find out in Chapter 5 of Book I, a framework offers common code providing generic functionality. The iPhone OS provides a set of frameworks for incorporating technologies, services, and features into your apps. The framework is designed to easily integrate your code; with the framework in place, all you need to do is add the specific functionality that you want in the app — the content as well as the controls and views that enable the user to access and use that ...