Swift ios check if remote push notifications are enabled in ios9 and ios10

Question

How can I check if the user has enabled remote notifications on ios 9 or ios 10?

If the user has not allowed or clicked No I want to toggle a message asking if they

Answer 1

Here's a solution for getting a string describing the current permission that works with iOS 9 trough iOS 11, with Swift 4. This implementation uses When for promises.

import UserNotifications

private static func getNotificationPermissionString() -> Promise {
    let promise = Promise()

    if #available(iOS 10.0, *) {
        let notificationCenter = UNUserNotificationCenter.current()
        notificationCenter.getNotificationSettings { (settings) in
            switch settings.authorizationStatus {
            case .notDetermined: promise.resolve("not_determined")
            case .denied: promise.resolve("denied")
            case .authorized: promise.resolve("authorized")
            }
        }
    } else {
        let status = UIApplication.shared.isRegisteredForRemoteNotifications ? "authorized" : "not_determined"
        promise.resolve(status)
    }

    return promise
}