ios - Class extension vs. subclassing in Swift? -

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i'am using third-party framework provides class instances have properties. in app, i'd add property instances. appropriate way scenario?

a) extending framework's class in app

b) creating subclass of framework's class , define new property need

thanks in advance

it's

b)

because adding (stored) properties in class extension not supported.

there 2 important rules using extensions:

  • extensions can add new functionality type, cannot override existing functionality

  • extensions can add new computed properties, cannot add stored properties, or add property observers existing properties


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