Objective C

Objective C is a programming language, which is sleeted by Apple for developing the application for iPhone and Mac systems. Here we are providing easy to learn Objective C tutorials. We will be explaining the programming language with easy to learn examples. You will find these Objective C tutorials very useful in gaining the core concepts easily and in very less time.

So, let's get started with Objective C.

1. About Objective C Tutorial
   About the Objective C tutorial presented here. In this complete guide of Objective C you will be learning the programming concepts by doing the coding. We follow the learn by doing concepts.
    
2. Objective C Introduction
   This section provides you the basic introduction about Objective C programming language. Objective C is very old programming language and it was designed and developed in 1980. Now Objective C has become popular once again as it is being used by Apple to developing applications for Mac system and iPhone.
    
3. Why Objective C?
   In this section we will learn about the importance of Objective C and "Why Objective C?" is used as programming language to develop applications for Mac System and iPhone.
    
4. Objective C Hello World Example
   In this section I will show you how to develop Objective C Hello World program.
    
5. Objective C on Windows
   In this section you will learn how to use Objective C on Windows machine. We will download and install Objective C Windows compiler. On windows GNU C compiler can be used to compile the Objective C program.
    
6. Objective C on Mac
   I this section we will show you how to compile and run Objective C program on Mac machine.
    
7. Compiling Objective C
   In this section we will show you how to compile Objective C program on windows and Max OS x machine. Compiling Objective C program is necessary as it generates the executable program that can run.
     
8. Objective-C keywords
   In this section we will know about the keywords used in objective-C language. Objective-C is a superset of C language, so program written in c and C++ should compile as objective-c.
     
9. Message Expressions and comments
   Like C and C++ objective-C provides comments. Programmer can use single or multi line comments in the code according to the need. Message expressions are enclosed in square brackets.
    
10. Class and Method declaration and definitions
    Because of objective-C is the extension of ANSI-C and it follows an object oriented approach so provides classes and objects. The way to declare and define classes and creation of object is little bit different from C and C++. 
      
11. Objective-C program with multiple parameter
    Objective-C enables programmer to use method with multiple parameter. These parameter can be of same type or of different type.
    This is a sample program that shows sum of three numbers as output.
      
12. Constructors
    Objective-C enables user to define constructor with the help of self and super keywords. Like java Objective-C has parent class and programmer can access its constructor by statement [super init], this statement returns a instance of parent class which we assign to the 'self' keyword, actually 'self' plays same role as this keyword in C++ and Java. 
      
13. Access Modifiers and Garbage Collection
    Previously it was a requirement to allocate and release memory manually to assist with this problem it provides a reference-counting memory management system through retain and release keywords.
       
14. Class level access
    Objective-C provides facility of class level access. In the examples given above we have used '-' sign before method, '-' means instance level access. Now we will see how to define method that can be access on class level.
      
15. Exception handling in Objective-C
    Objective-C provide exception handling to handle exceptional conditions so that code can be easier to write, easy to detect exceptions in the code and easier to maintain as well. To take support of exception handling make sure the -fobj-exceptions flag is turned on.
      
16. Objective-C Inheritance
    Objective-C enables programmer to inherit common methods and properties from other class, known as inheritance. Class from methods and properties are inherited known as Base Class and class that inherits known as Derived Class.
      
17. Dynamic Types in Objective-C
    Objective-C provides many methods to work with dynamic types. With these methods programmer can check that object is of the given class or not, given method is member of the given class or not etc. 
       
18. Objective-c memory management: retain and release
    Objective-C uses two methods retain and release. In Objective-C each object has an internal counter that is used to keep track of all references used by the objects or object has. 
      
19. Objective-c Dealloc
    When an object contains another objects so before deallocation programmer needs to release all those objects. This example shows how to use method dealloc, when you want to deallocate an object that has already some other objects attached. 
      
20. Categories
    When programmer wants to add some more functionality to the class, typically extend the class. But this is not a right way everywhere, so like ruby Objective-C also provides categories to achieve this.
     
21. Posing
    Posing is similar to category but it works a little bit different with the category. It enable programmers to pose subclass to super class globally. When subclass posed on super class method which are same in both classes are override with the subclass methods.