Swift 3 - dynamic vs @objc

Question

What\'s the difference between marking a method as @objc vs dynamic, when would you do one vs the other?

Below is Apple\'s definition for dynamic.

Answer 1

To work with Objective-C from Swift you have at least two reserved words:

• @objc[About] - Compile time - To expose Swift's api for Objective-C runtime. For example a framework which was written on Swift can use @objc for:

  1. using #selector[About] in a Swift code
  2. opening public functionality for Objective-C consumers

• dynamic - Run time - to enable a message dispatch(Objective-C's world) for NSObject object, which is different than virtual dispatch (table dispatch) (Swift's world). It is used for:

  1. KVO
  2. class extensions to have a possibility to override an extension function
  3. swizzling[Example]

Before Swift v4 dynamic included @objc