Xcode 8：不能从非开放类继承
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Xcode 8: Cannot inherit from non-open class
提问by Yann Bodson
After I updated to latest Xcode 8, I get this error:
更新到最新的 Xcode 8 后，出现此错误：
Cannot inherit from non-open class ‘WDBaseViewController' outside of its defining module
无法从其定义模块之外的非开放类“WDBaseViewController”继承
My class is declared like this
我的班级是这样声明的
public class ProfileViewController: WDBaseViewController {
}
But I didn't change the framework.
但我没有改变框架。
回答by Yann Bodson
Short answer:
简答：
To be able to subclass it, the base class WDBaseViewControllerneeds to be defined as openinstead of publicin the framework you are using.
为了能够对其进行子类化，WDBaseViewController需要定义基类open而不是public在您使用的框架中。
open class WDBaseViewController {
...
}
If it's an internal framework you can do it yourself, otherwise you will have to wait for the author to support Swift 3.
如果是内部框架可以自己做，否则就得等作者支持Swift 3了。
Long answer:
长答案：
Swift 3 is bringing significant changes to access control.
Swift 3 为访问控制带来了重大变化。
Swift 2 only had 3 access levels:
Swift 2 只有 3 个访问级别：
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.
private：实体仅在定义它们的源文件中可用。internal：实体可用于包含定义的整个模块。public：实体旨在用作 API，并且可以被任何导入模块的文件访问。
Swift 3 is adding 2 more access levels (openand fileprivate) and changing the meaning of private:
Swift 3 增加了 2 个访问级别（open和fileprivate）并更改了 的含义private：
private: symbol visible within the current declaration only.fileprivate: symbol visible within the current file.internal: symbol visible within the current module.public: symbol visible outside the current module.open: for class or function to be subclassed or overridden outside the current module.
private: 仅在当前声明中可见的符号。fileprivate: 符号在当前文件中可见。internal: 符号在当前模块中可见。public: 符号在当前模块外可见。open: 用于在当前模块之外子类化或覆盖类或函数。
