Apple provides you with all the tools you need to create great Cocoa applications, for free. This set of tools, known under the name Xcode, comes with Mac OS X, or you can download it from the developer section on Apple's website.
Several good books on programming for the Mac exist, but they assume that you already have some programming experience. This book doesn't. It teaches you the basics of programming, in particular Objective-C programming, using Xcode. After some 5 chapters, you will be able to create a basic program without a Graphical User Interface (GUI). After a few more chapters, you will know how to create simple programs with a GUI. When you have finished this booklet, you will be ready for the above-mentioned more advanced books. You will have to study those too, because there is a lot to learn. For now though, don't worry because this book takes it easy.
As you will see, some paragraphs are displayed in a box like this:
We suggest you read each chapter (at least) twice. The first time, skip the boxed sections. The second time you read the chapters, include the boxed text. You will in effect rehearse what you have learned, but learn some interesting tidbits which would have been distracting the first time. By using the book in this way, you will level the inevitable learning curve to a gentler slope.
This book contains dozens of examples, consisting of one or more lines of programming code. To make sure you associate an explanation to the proper example, every example is labeled by a number placed between square brackets, like this: [1]. Most examples have two or more lines of code. At times, a second number is used to refer to a particular line. For example, [1.1] refers to the first line of example [1]. In long code snippets, we put the reference after a line of code, like this:
//[1] volume = baseArea * height; // [1.1]
Programming is not a simple job. For your part, it requires some perseverance and actually trying all the stuff taught in this book yourself. You cannot learn how to play the piano or drive a car solely by reading books. The same goes for learning how to program. This book is in an electronic format, so you do not have any excuse not to switch to Xcode frequently. Therefore, as of chapter 5, we suggest you go through each chapter three times. The second time, try the examples for real, and then make small modifications to the code to explore how things work
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