Background fetch not working - Not firing notification

Question

I'm trying to implement Background Fetch API in my app for that I've configured as below.

I've enabled Background Fetch from Capabilities.

In AppDelegate.swift

Added this in didFinishLaunchingWithOptions method

UIApplication.shared.setMinimumBackgroundFetchInterval(30)

Implemented this method too to perform task.

func application(_ application: UIApplication, performFetchWithCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {

    debugPrint("New notification fired from AppDelegate...!!")

    let notif = UNMutableNotificationContent()
    notif.title = "New notification from App delegate"
    notif.subtitle = "Cool App!"
    notif.body = "I liked it!"

    UNUserNotificationCenter.current().requestAuthorization(options: [.sound, .badge, .alert], completionHandler: { (isGranted, error) in

        DispatchQueue.main.async {
            let notifTrigger = UNTimeIntervalNotificationTrigger(timeInterval: 0.1, repeats: false)
            let request = UNNotificationRequest(identifier: "myNotification", content:  notif, trigger: notifTrigger)

            UNUserNotificationCenter.current().add(request) { (error) in
                if error != nil{
                    print(error!)
                } else {
                    // do something
                }
            }
        }
    })

}

After configuring all the things local notification not firing. Why so?

Am I missing something?

I've also tried this tutorial

Any help will be appreciated!

You should request notification permissions as soon as your app launches. You can't request permissions when your app is already in the background. — Paulw11, Jul 16 '18 at 21:51
So take that code out of this function and get rid of the dispatchQueue.main — Paulw11, Jul 17 '18 at 05:10

score 1 · Answer 1 · answered Jul 18 '18 at 07:06

You are not calling completionHandler in performFetchWithCompletionHandler. I am able to test BackgroundFetch with below code:

DispatchQueue.main.async {
                let notifTrigger = UNTimeIntervalNotificationTrigger(timeInterval: 6.0, repeats: false)
                let request = UNNotificationRequest(identifier: "myNotification", content:  notif, trigger: notifTrigger)

                UNUserNotificationCenter.current().add(request) { (error) in
                    if error != nil{
                        print(error!)
                        completionHandler(.failed) // Add this line
                    } else {
                        completionHandler(.noData) // Add this line
                    }
                }
            }

You can test Background Fetch with below steps:

Run your application.
Goto Xcode toolbar.
Select Debug > Simulate Background Fetch.

Now you will able to Test Background Fetch.

score 0 · Answer 2 · answered Jul 29 '19 at 23:00

0

There is similar question about this:

Background Fetch Does Not Appear to Fire

Try to force it to run on the simulator, If fetch event works in simulator, that proves that everything is correctly set up. There's nothing you can do but wait.

answered Jul 29 '19 at 23:00

Mike D3ViD Tyson

1,701
1
21
31

Background fetch not working - Not firing notification

2 Answers2