问题
As of Xcode 8 beta 6 I now get the compile error "Cannot inherit from non-open class (Class)" outside of its defining module"
The class I was inheriting from was part of a separate Swift framework but my project compiled for Xcode 8 beta 5. What do I need to change to get my project to compile again?
回答1:
Found the answer myself.
In Swift 3 you can now mark a class as open instead of public this allows files outside of the module to subclass that class.
Simply replace public in your module class with open.
Reference here.
回答2:
The class you inherit from needs to be defined as open instead of public.
A bit more context on the changes to access control in Swift 3:
Swift 2 only had 3 access levels:
private: entities are available only from within the source file where they are defined.internal: entities are available to the entire module that includes the definition.public: entities are intended for use as API, and can be accessed by any file that imports the module.
Swift 3 is adding 2 more access levels (open and fileprivate) and changing the meaning of private:
private: symbol visible within the current declaration only.fileprivate: symbol visible within the current file.internal: symbol visible within the current module or default access modifier.public: symbol visible outside the current module.open: for class or function to be subclassed or overridden outside the current module.
来源：https://stackoverflow.com/questions/38979371/cannot-inherit-from-non-open-class-swift