- #OS X PROGRAMMING LANGUAGE HOW TO#
- #OS X PROGRAMMING LANGUAGE FOR MAC OS#
- #OS X PROGRAMMING LANGUAGE SOFTWARE#
Note that insertObject:atIndex: is one selector, not two. For example, to add an object at a particular index, you could use the following: If you have multiple arguments, the selector will have multiple parts. For example, to add objects to the end of the array, you use the addObject: method (assume that bar is a pointer to another object): If a method takes an argument, the method name (called a selector) will end with a colon. What about destroying the object when we no longer need it? We will talk about this in the next chapter. As a consequence, you will always nest the message sends like this: NSMutableArray *foo The method init returns the newly initialized object. You can also send messages to classes, as demonstrated by sending the message alloc to the class NSMutableArray. We would say, “ foo is the receiver of the message init.” Note that a message send consists of a receiver (the object foo points to) and a message ( init) wrapped in brackets. Take a long look at the last line it sends the message init to the object that foo points to. The init method will handle this task, so you might write code like this: NSMutableArray *foo In this case, it points to an object.īefore using the object that foo points to, you would need to make sure that it is fully initialized. While working with Objective-C, it is important to remember that foo is just a pointer. You could hold onto that pointer in a variable like this: NSMutableArray *foo This method returns a pointer to the space that was allocated for the object.
You can create a new instance of NSMutableArray by sending the message alloc to the NSMutableArray class like this:
#OS X PROGRAMMING LANGUAGE HOW TO#
In this section, you will learn how to create an object and send messages to it.Īs an example, we will use the class NSMutableArray. Creating and Using InstancesĬhapter 1 mentioned that classes are used to create objects, that the objects have methods, and that you can send messages to the objects to trigger these methods. If you do not, our own Objective-C Programming: The Big Nerd Ranch Guide or Apple’s The Objective-C Language offer more gentle introductions. If you fit the profile, you will find learning Objective-C to be easy. This chapter assumes that you already know a little C and something about objects and introduces you to the basics of Objective-C. Teaching C and basic object-oriented concepts could consume an entire book. In Xcode projects, LLVM is the default compiler.Ĭocoa was developed using Objective-C, and most Cocoa programming is done in Objective-C. More recently, Apple has become heavily involved in the clang/LLVM (Low Level Virtual Machine) open source compiler projects, which are much faster and more versatile than gcc.
#OS X PROGRAMMING LANGUAGE SOFTWARE#
Rather, it is an open standard that has been included in the Free Software Foundation’s GNU C compiler (gcc) for many years. Objective-C is not a proprietary language. In fact, it was originally just a C preprocessor and a library. Objective-C is a very simple extension of the C language. Starting with C, Brad Cox added Smalltalk-like classes and message-sending mechanisms. Smalltalk was an elegant untyped object-oriented language. Once upon a time, a man named Brad Cox decided that it was time for the world to move toward a more modular programming style.
#OS X PROGRAMMING LANGUAGE FOR MAC OS#
Cocoa Programming for Mac OS X, 4th Edition
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