To understand inheritance, think about it as a perfect biological tree, where you have inherited some behavioral traits from your father, but more than that you have your own. Something like this happens in Objective-C when a class is inherited from another.
Basic samples are the classes whose names start with NS
provided by Cocoa and Cocoa Touch, such as NSString
, NSArray
, and NSDictionary
. They are all inherited from NSObject
. Each of them has their particular methods to handle the different types of contents they hold, but everyone shares methods such as alloc
and init
. These two class methods, inherited from NSObject
, respectively allocate memory and initialize the object:
The alloc
method will rarely be overridden, performing a single task and allocating memory to the object being created. However, another inheritance example is the init
method, which is also inherited from NSObject
. It received modifications in each child class, creating other initialization methods to quickly...