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Chapter 1: Computer Programming Exposed!

easy or difficult is not just the language, but the application development

tools available to you, as well.

Objective-C has its fans and its detractors, My advice to you is to ignore both

sides and get on with your development. There are some things I really like

about the language, and others I don’t; but in essence, it is what it is, and it is

what you’ll use.

Running your program in

a runtime environment

One of features of Objective-C is its runtime system. This is one of those things

that gets linked into your program in Step 4 in the section “Creating a computer

program.” It acts as a kind of operating system (like the Mac or iPhone OS) for

an individual Objective-C program. It is this runtime system that is responsible

for making some of the very powerful features of Objective-C work.

Objective-C’s runtime environment also makes it possible to use tools like

Interface Builder (I explain Interface Builder in Chapters 17 and 18) to create

user interfaces with a minimum of work (I’m all for that, and after you learn

about Interface Builder, you will be, too).

Using frameworks and libraries

The framework you will use is called Cocoa. It came along with Objective-C

when Apple acquired NeXT In 1996 (when it was called NextSTEP). I have

worked in many development environments over my life, and Objective-C and

Cocoa are hands down my favorite.

Cocoa allows you to write applications for Mac OS X, and a version of it allows

you to write applications for the iPhone. If the operating system does the

heavy lifting vis-à-vis the hardware, the framework provides all the stuff you

need to make your application an application. It provides support for win-

dows and other user-interface items as well as many of the other things that

are needed in most applications. When you use Cocoa, to develop your appli-

cation all you need to do is add the application’s specific functionality — the

content and the controls and views that enable the user to access and use

that content — to the Cocoa framework.

Now, two excellent books explain the use of frameworks on the Mac and

iPhone. One is Cocoa Programming for Mac OS X For Dummies by Erick

Tejkowski. The other is iPhone Application Development For Dummies by Neal

Goldstein (I know, a shameless plug).

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