Bob Kressin - Objective-C

Objective-C

Jiva DeVoe

Objective-C

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Copyright 2011 by Wiley Publishing, Inc., Indianapolis, Indiana

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ISBN: 978-0-470-47922-3

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Dedication

For my wife, Dawn, and my children, Robert, Alex, and Izzy. You are, and always will be, the most important people in the world to me.

About the Author

Jiva DeVoe has been writing software for nearly 25 years, starting with his Commodore VIC-20 using BASIC and assembly language, and gradually working his way through C, C++, Python, Ruby, Java and finally Objective-C. In 2001, he founded Random Ideas, LLC, a software company dedicated to building great applications for the Mac. When the iPhone SDK was announced, he was honored to be selected as one of the earliest developers to have access to the SDK, and using it, he developed several applications that were available in the iTunes App Store when it launched on July 11, 2008. Since that time, his iPhone applications have received several awards, including being chosen as among the Top 100 apps and games in the App Store, and been featured as Apple Staff Picks and in Apple Advertisements. Today, Jiva continues to work full time for his company, Random Ideas, developing great iPhone and Mac applications. He lives with his wife, three children, and two basset hounds in the dusty desert of Arizona.

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Preface

Objective-C gets a raw deal in the IT industry. Though it's a powerful and dynamic object oriented language, it doesn't get nearly the amount of recognition that C++, Java, and others get.

When I wrote Cocoa Touch for iPhone OS 3, I knew that it needed a companion book, one which helped people over the hump of learning Objective-C before moving on to the higher level frameworks, Cocoa, and Cocoa Touch.

So when the opportunity came to write a book dedicated to Objective-C, the language, I jumped at it!

In the end, I feel I have been given an opportunity to contribute to the foundation of new Mac, iPhone and iPad developers knowledge through this book, and I'm tremendously excited by that. I love the idea that this book might be a catalyst to helping Objective-C grow, not just on these, but across many different platforms. There's no reason that Objective-C shouldn't be used more on platforms such as Unix, Windows, and so on.

As a reader, you are expected to have only a limited knowledge of computers. I have tried to approach the subject from the absolute bare essentials, but you will need at least a basic background in how to navigate around a computer.

If you already know some programming languages, that won't hurt you here. Some of what I discuss will be review for you, but don't worry, there's plenty of specifics for Objective-C that you will pick up.

If you already have a background in Objective-C, I hope that you will find some nuggets of information you didn't know in this book. I've tried to keep it in an accessible form so that you can look up specifics that you're looking for. You may not read it cover to cover, but it should give you the ability to jump to specific parts and gain insight into how to do what you are looking to do.

With regard to conventions used within this book, I've tried to be reasonably consistent, and also tried to generally err on the side of Apple conventions when prudent. The only notable exception has been in my use of the phrase method to indicate functions on instances and classes. Apple generally prefers the term message. This is in part due to the influence of Smalltalk on Objective-C.

When referring to keyboard shortcuts, I opted to use the term Command-Key to indicate keyboard shortcuts using the key directly to the left of the space key on most Apple keyboards. You may also know this as the Apple key, since prior to only a few years ago, it included a small Apple logo on it. Additionally, the key next to the Command-Key, has been called the Option-Key and the key next to that, the Control-Key. These should all be consistent with Apple documentation conventions.