iosswiftusernotifications

Sending local notifications in SWIFT


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??


Solution

  • 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])
        }
    
    }