Sams Teach Yourself Cocoa Touch™ Programming in 24 Hours

Hour 2. Handling Interaction

What You’ll Learn in This Hour:

• Understanding Objective-C objects

• Binding an object to the user interface

• Managing memory

• Invoking methods on nil

• Understanding Objective-C type checking

Now that you’ve installed the development tools and you’ve built a basic Calculator UI, it is time to make it useful. You’ll write code to give your calculator the ability to do arithmetic. As all iPhone code is written in Objective-C, you start learning Objective-C this hour. I cover the Objective-C objects, memory management, invoking methods on nil, and Objective-C type checking. You’ll also learn how to bind an object to the UI and how to debug with NSLog().

Objective-C

Objective-C adds a thin layer of object-oriented ...