How to pass swift enum with @objc tag

Question

I need to define a protocol which can be called in a class that use some Objective-c type

But doing that doesn\'t work:

enum NewsCellActionType: Int          


        

Answer 1

Apple just announced today that Swift 1.2 (included with xcode 6.3) will support exposing enums to objective-c

https://developer.apple.com/swift/blog/

Answer 2

Swift enums are very different from Obj-C (or C) enums and they can't be passed directly to Obj-C.

As a workaround, you can declare your method with an Int parameter.

func newsCellDidSelectButton(cell: NewsCell, actionType: Int)

and pass it as NewsCellActionType.Vote.toRaw(). You won't be able to access the enum names from Obj-C though and it makes the code much more difficult.

A better solution might be to implement the enum in Obj-C (for example, in your briding header) because then it will be automatically accessible in Swift and it will be possible to pass it as a parameter.

EDIT

It is not required to add @objc simply to use it for an Obj-C class. If your code is pure Swift, you can use enums without problems, see the following example as a proof:

enum NewsCellActionType : Int {
    case Vote = 0
    case Comments
    case Time
}

protocol NewsCellDelegate {
    func newsCellDidSelectButton(cell: UITableViewCell?, actionType: NewsCellActionType    )
}

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate, NewsCellDelegate {

    var window: UIWindow?

    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: NSDictionary?) -> Bool {
        self.window = UIWindow(frame: UIScreen.mainScreen().bounds)

        self.window!.backgroundColor = UIColor.whiteColor()
        self.window!.makeKeyAndVisible()

        test()

        return true;
    }

    func newsCellDidSelectButton(cell: UITableViewCell?, actionType: NewsCellActionType) {
        println(actionType.toRaw());
    }

    func test() {
        self.newsCellDidSelectButton(nil, actionType: NewsCellActionType.Vote)
    }
}