使用未声明的类型错误

Question

我尝试添加fb登录，但只是这个错误，我该如何解决？

func application(application: UIApplication, open url: URL, options: protocol<UIApplicationOpenURLOptionsKey, id>) -> Bool {
        var handled: Bool = FBSDKApplicationDelegate.sharedInstance().application(application, openURL: url, sourceApplication: options[UIApplicationOpenURLOptionsSourceApplicationKey], annotation: options[UIApplicationOpenURLOptionsAnnotationKey])
        // Add any custom logic here.
        return handled
    }