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iOS

Alex Hamilton
Alex Hamilton
4,103 Points
Posted by Alex Hamilton
Alex Hamilton
4,103 Points

Mutable dictionary - setDictionary?

Code 2/3 NSDictionary - Objective C Basics -Asks to create an NSMutableDictionary named albumMutable and then to use dictionaryWithDictionary class method (NSDictionary)... could we use setDictionary instance method on the mutable class instead? I don't see a class method on NSMutableDictionary called dictionaryWithDictionary............ can we use all the class methods from NSDictionary in NSMutableDictionary due to inheritance?

2 Answers

John W
John W
21,558 Points
John W
John W
21,558 Points

Yes, NSMutableDictionary is a subclass of NSDictionary, so you can use all NSDictionary methods with NSMutableDictionary. In fact, there is a whole set of nice properties and corollaries you get from inheritance that make the object-oriented programming paradigm so popular.

Alex Hamilton
Alex Hamilton
4,103 Points
Alex Hamilton
Alex Hamilton
4,103 Points

Great! Thanks for the reply John!