NEW: Master Swift design patterns with my latest book! >>

What is the @objcMembers attribute?

Written by Paul Hudson    @twostraws

By default Swift generates code that is only available to other Swift code, but if you need to interact with the Objective-C runtime – all of UIKit, for example – you need to tell Swift what to do.

If you just want to expose a single method or property, you can mark that method using the @objc attribute. However, if you want all methods in a class to be exposed to Objective-C you can use a shortcut: the @objcMembers keyword:

@objcMembers class MyController: UIViewController {
    func login() {

    }
}

In that code, the login() method will automatically be exposed to Objective-C in the same way as if it had been marked with @objc, because the whole class it’s inside is marked with @objcMembers.

Available from iOS 8.0

Did this solution work for you? Please pass it on!

Other people are reading…

About the Swift Knowledge Base

This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.

Want to build macOS apps?

Hacking with macOS delivers 18 awesome projects that teach you macOS development in no time – take control of your desktop today!

Click here to visit the Hacking with Swift store >>