Sending local notifications in SWIFT - ios

Question

I added this code to my first ViewController
// Step-1 Ask permission from User
let center = UNUserNotificationCenter.current()
center.requestAuthorization(options: [.badge,.sound,.alert]) { granted, error in
if error == nil {
print("User permission is granted : \(granted)")
}
}
// Step-2 Create the notification content
let content = UNMutableNotificationContent()
content.title = "Hello"
content.body = "Welcome"
// Step-3 Create the notification trigger
let date = Date().addingTimeInterval(1)
let dateComponent = Calendar.current.dateComponents([.year,.month,.day,.hour,.minute,.second], from: date)
let trigger = UNCalendarNotificationTrigger(dateMatching: dateComponent, repeats: false)
// Step-4 Create a request
let uuid = UUID().uuidString
let request = UNNotificationRequest(identifier: uuid, content: content, trigger: trigger)
// Step-5 Register with Notification Center
center.add(request) { error in
but 5 seconds pass without any notification shown. What is wrong? Could somebody show me how to fix it??

Answer 1

The notification comes but when the app is foreground it won't show until you implement UNUserNotificationCenterDelegate method
UNUserNotificationCenter.current().delegate = self
func userNotificationCenter(_ center: UNUserNotificationCenter,
willPresent notification: UNNotification,
withCompletionHandler completionHandler: #escaping (UNNotificationPresentationOptions) -> Void) {
completionHandler([.sound,.alert])
}
Also set
let date = Date().addingTimeInterval(5)
to give it some time until app hits so you can test it after clicking home button
import UIKit
class ViewController: UIViewController , UNUserNotificationCenterDelegate {
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
let center = UNUserNotificationCenter.current()
center.delegate = self
center.requestAuthorization(options: [.badge,.sound,.alert]) { granted, error in
if error == nil {
print("User permission is granted : \(granted)")
}
}
// Step-2 Create the notification content
let content = UNMutableNotificationContent()
content.title = "Hello"
content.body = "Welcome"
// Step-3 Create the notification trigger
let date = Date().addingTimeInterval(5)
let dateComponent = Calendar.current.dateComponents([.year,.month,.day,.hour,.minute,.second], from: date)
let trigger = UNCalendarNotificationTrigger(dateMatching: dateComponent, repeats: false)
// Step-4 Create a request
let uuid = UUID().uuidString
let request = UNNotificationRequest(identifier: uuid, content: content, trigger: trigger)
// Step-5 Register with Notification Center
center.add(request) { error in
}
}
func userNotificationCenter(_ center: UNUserNotificationCenter,
willPresent notification: UNNotification,
withCompletionHandler completionHandler: #escaping (UNNotificationPresentationOptions) -> Void) {
completionHandler([.sound,.alert])
}
}