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General Discussion

Posted by Homer Denson
Homer Denson
2,024 Points

Inheritance Compositions question

I'm fairly new to Obj C, and I just want to know when is the best time to use inheritance and compositions? Also when exactly do I use "@property (nonatomic, strong)? when I have a property that belongs to a class? which my be an easy answer.

1 Answer

JEONG EUN KIM
JEONG EUN KIM
2,270 Points
JEONG EUN KIM
JEONG EUN KIM
2,270 Points

Composition means consists of many things. Mean Single big object/class consists of many objects in it.

Ex:

@interface Computer { CPU * ptrCpu; Monitor* ptrMonotor; Mouse* ptrMouse; } @end

Only objects are said to be composed not primitive data type like int ,char etc.

Composition set up "has a" relationship. Its represent that Main object own other small small objects. Ex: Computer has a Cpu.

Inheritance set up "is a" relationship. Ex:-Triangle is a shape