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iOS Objective-C Basics (Retired) Introduction to Objective-C From Structs to Objects

Few Clarification


  1. In the video. The instructor declare variable inside the "Sphere : NSObject" bracket but he declare the methods outside of the bracket. Is this important ? If it is, can you please explain why?

  2. I came from a C++ background so I would like to know what's the difference between a method and a function. Also what's the difference between instance method and class method.

  3. I understand that Sphere inherit the NSObject class. So don't we have to " #import <NSObject> " or something of this nature ?