Using the API in Xcode
So how are you supposed to know when a class requires a delegate or not? How do you find out what properties a class supports or even what messages it responds to? What you need is an API to see what havoc you can wreak using these built-in Foundation and UIKit classes.
Of course, the iPhone SDK wouldn’t be complete without documentation, and you can conveniently access it both in Xcode and on the web. There are several ways to get to the information you need:
• Find the class or method you’re interested in, right-click it, and select Find Selected Text in API Reference. This launches the integrated API reference, as shown in the following image.
• In Xcode, select Help > Documentation from the top menubar.
• Search for ...