是否应该覆盖 deinit 以删除 Swift 中的观察者？
Should deinit be overridden to remove observers in Swift?
队友编写的代码如
deinit {
NotificationCenter.default.removeObserver(self)
}
我评论删除它，因为框架已经照顾到观察者。如果没有副作用，队友希望保留此代码。现在，即使我们保留上面的代码会有任何副作用吗？
我是否也应该在 deinit 中调用 super.deinit()？
是的，覆盖有效
deinit()
正如评论中指出的那样。不需要调用 Super。我在苹果文档中证实了这一点。
在我看来，明确清理是个好主意。特别是涉及到线程、通知和计时器时。
从 iOS 9 开始，如果您不使用基于块的观察者，则无需自己删除观察者。系统会为你做这件事，因为它在可能的情况下为观察者使用归零弱引用。
If the observer is able to be stored as a zeroing-weak reference the
underlying storage will store the observer as a zeroing weak
reference, alternatively if the object cannot be stored weakly (i.e.
it has a custom retain/release mechanism that would prevent the
runtime from being able to store the object weakly) it will store the
object as a non-weak zeroing reference. This means that observers are
not required to un-register in their deallocation method.
Block based observers via the -[NSNotificationCenter
addObserverForName: object: queue: usingBlock] method still need to be
un-registered when no longer in use since the system still holds a
strong reference to these observers.
而对于 super.deinit() 苹果说
Deinitializers are called automatically, just before instance
deallocation takes place. You are not allowed to call a deinitializer
yourself. Superclass deinitializers are inherited by their subclasses,
and the superclass deinitializer is called automatically at the end of
a subclass deinitializer implementation. Superclass deinitializers are
always called, even if a subclass does not provide its own
deinitializer.
队友编写的代码如
deinit {
NotificationCenter.default.removeObserver(self)
}
我评论删除它，因为框架已经照顾到观察者。如果没有副作用，队友希望保留此代码。现在，即使我们保留上面的代码会有任何副作用吗？
我是否也应该在 deinit 中调用 super.deinit()？
是的，覆盖有效
deinit()
正如评论中指出的那样。不需要调用 Super。我在苹果文档中证实了这一点。
在我看来，明确清理是个好主意。特别是涉及到线程、通知和计时器时。
从 iOS 9 开始，如果您不使用基于块的观察者，则无需自己删除观察者。系统会为你做这件事，因为它在可能的情况下为观察者使用归零弱引用。
If the observer is able to be stored as a zeroing-weak reference the underlying storage will store the observer as a zeroing weak reference, alternatively if the object cannot be stored weakly (i.e. it has a custom retain/release mechanism that would prevent the runtime from being able to store the object weakly) it will store the object as a non-weak zeroing reference. This means that observers are not required to un-register in their deallocation method.
Block based observers via the -[NSNotificationCenter addObserverForName: object: queue: usingBlock] method still need to be un-registered when no longer in use since the system still holds a strong reference to these observers.
而对于 super.deinit() 苹果说
Deinitializers are called automatically, just before instance deallocation takes place. You are not allowed to call a deinitializer yourself. Superclass deinitializers are inherited by their subclasses, and the superclass deinitializer is called automatically at the end of a subclass deinitializer implementation. Superclass deinitializers are always called, even if a subclass does not provide its own deinitializer.