UserNotifications iOS 10 Example

UserNotificationsExample.swift

import UserNotifications

// 1. Request Permission 
func requestAuthorization() {
    UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .sound]) { (granted, error) in
        if granted {
            // Success
        } else {
            // Error
            print(error?.localizedDescription)
        }
    }
}

// 2. Create Notification
func createNotification() {
    let content = UNMutableNotificationContent()
    content.title = "New cuddlePix!"
    content.subtitle = "What a treat"
    content.body = "Cheer yourself up with a hug 🤗"
    let attachment = try! UNNotificationAttachment(identifier: randomImageName, url: imageURL, options: .none)
    content.attachments = [attachment]
    let trigger = UNTimeIntervalNotificationTrigger(timeInterval: seconds, repeats: false)
    let request = UNNotificationRequest(identifier: randomImageName, content: content, trigger: trigger)
    UNUserNotificationCenter.current().add(request) { (error) in
        if let error = error {
            print(error)
            completion(false)
        } else {
            completion(true)
        }
    }
}

// 3. Foreground Notification Support
// Auto show the notification with alert type, dont need to create custome one
extension AppDelegate: UNUserNotificationCenterDelegate {
    func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void) {
        completionHandler(.alert)
    }
}

// 4. Querying Notification
func queryNotification(callback: (() -> ())? = .none) {
    // 4.0 Process in the background
    let group = DispatchGroup()
    let notificationCenter = UNUserNotificationCenter.current()
    let dataSaveQueue = DispatchQueue(label: "com.xxx.yyy")
    
    // 4.1 Get notification settings
    group.enter()
    notificationCenter.getNotificationSettings { (settings) in
        dataSaveQueue.async(execute: {
            // Do what you want
            group.leave()
        })
    }
    // 4.2 Get pending notification request
    group.enter()
    notificationCenter.getPendingNotificationRequests { (request) in
        dataSaveQueue.async(execute: {
            // Do what you want
            group.leave()
        })
    }
    
    // 4.4 Get Delivered Notification
    group.enter()
    notificationCenter.getDeliveredNotifications { (notifications) in
        dataSaveQueue.async(execute: {
            // Do what you want
            group.leave()
        })
    }
    
    // 4.5 Notification for process
    group.notify(queue: DispatchQueue.main) {
        if let callback = callback {
            callback()
        } else {
            // Do what you want
        }
    }
}

// 5. Remove pending notification request
func removePendingRequest(request: UNNotificationRequest) {
    UNUserNotificationCenter.current().removePendingNotificationRequests(withIdentifiers: [request.identifier])
}

// 6. Custom Notification view (NotificationExtension)
// 6.1 Create Notification Extension by File > New > Target > Notification Content Extension
// 6.2 Custom interface in .storyboard and .swift file
// 6.3 Input data to custom interface
func didReceive(_ notification: UNNotification) {
    guard let attachment = notification.request.content.attachments.first else {
        return
    }
    if attachment.url.startAccessingSecurityScopedResource() {
        let imageData = try? Data.init(contentsOf: attachment.url)
        // Do what you want with the image data
        attachment.url.stopAccessingSecurityScopedResource()
    }
}
// 6.4 Add NSExtension > NSExtensionAttributes > UNNotificationExtensionCategory = "<Unique string>" in Extension > Info.plist
// Update code in 2. function
content.categoryIdentifier = newCuddlePixCategoryName

// 7. Handle Action
// 7.1 AppDelegate >     
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey : Any]? = nil) -> Bool {
    configureUserNotification()
}

func configureUserNotification() {
    let starAction = UNNotificationAction(identifier: "star", title: "🌟 star my cuddle 🌟", options: [])
    let category = UNNotificationCategory(identifier: "<Unique string>", actions: [starAction], intentIdentifiers: [], options: [])
    UNUserNotificationCenter.current().setNotificationCategories([category])
}

// 7.2 Notification Extension > NotificationViewController
func didReceive(_ response: UNNotificationResponse, completionHandler completion: @escaping (UNNotificationContentExtensionResponseOption) -> Void) {
    if response.actionIdentifier == "xxx" {
        // Do what you do
        let time = DispatchTime.now() +
            DispatchTimeInterval.milliseconds(2000)
        DispatchQueue.main.asyncAfter(deadline: time) {
            completion(.dismissAndForwardAction)
        }
    }
}

// 7.3 Process in AppDelegate
func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse,
                            withCompletionHandler completionHandler: @escaping () -> Void) {
  print("Response received for \(response.actionIdentifier)")
  completionHandler()
}
// --- DOCUMENT ---
// 1. userNotificationCenter(_:willPresent:withCompletionHandler:) is called in the UNUserNotificationCenterDelegate (only in the foreground), and determines if the notification should present itself.
// 2. didReceive(_:) is called in the UNNotificationContentExtension and provides an opportunity to configure the custom notification's interface.
// 3. didReceive(_:completionHandler:) is called in the UNNotificationContentExtension after the user selects a response action.
// 4. userNotificationCenter(_:didReceive:withCompletionHandler:) is called in the UNUserNotificationCenterDelegate if the UNNotificationContentExtension passes it along via the dismissAndForwardAction response option.