I have multiple location notifications registered, often they overlap with each other. I want to limit to one fired notification per day, but the problem is that I do not have any way to cancel all the pending notifications when app is killed and can only do it when BGAppRefreshTaskRequest is triggered (which is not a common thing most of the times). And the worst part is that if user is in overlapping area he'll receive multiple push notifications at once.
Code to register notification:
let content = UNMutableNotificationContent()
content.title = "Title"
content.body = "Body"
content.sound = .default
content.userInfo = ["locationNotificationId" : id]
content.categoryIdentifier = "geofenceNotifications"
let region = CLCircularRegion(center: location,
radius: CLLocationDistance(range),
identifier: id)
region.notifyOnEntry = true
region.notifyOnExit = false
let trigger = UNLocationNotificationTrigger(region: region, repeats: false)
let request = UNNotificationRequest(identifier: id,
content: content,
trigger: trigger)
UNUserNotificationCenter.current().add(request, withCompletionHandler: { error in
if let error = error {
print(error)
}
})
What do I do to prevent other notifications being triggered after one is fired if app is in the background or killed?
Ok, so I managed to resolve the issue by monitoring region itself instead of using local push notification with UNLocationNotificationTrigger. The downsides are - I need to ask location access for background instead of "when in use" and I'm limited to 20 regions but it still better than uncontrolled flow of push notifications.
To read more about region monitoring: https://www.raywenderlich.com/5470-geofencing-with-core-location-getting-started#toc-anchor-004
Related
Im trying to schedule local notification every hour. The problem is that im getting the notification in such irregular time. Sometime in 10 minutes, or in second, or 30 minutes. Sometime i get like 10 notifications in the same second suddenly. I have no idea what is the mistake im doing here. I apologize in advance, i just started learning swift.
This is my code.
#objc func LocalNotificationHour() {
let user = UNUserNotificationCenter.current()
user.requestAuthorization(options: [.alert,.sound]) { (granted, error) in}
let content = UNMutableNotificationContent()
content.title = "Local Notification"
content.body = "Test."
let trigger = UNTimeIntervalNotificationTrigger(timeInterval: (60*60), repeats: true)
let uuid = UUID().uuidString
let request = UNNotificationRequest(identifier: uuid, content: content, trigger: trigger)
user.add(request) { (error) in print("Error")}
}
Is it possible that your function is being run multiple times, and therefore scheduling more than one notification to repeat? That would account for receiving multiple notifications at once/at times when you're not expecting them.
If that is the case, try adding the line user.removeAllPendingNotificationRequests() under let user = UNUserNotificationCenter.current(). This will remove any pending notifications your app may have scheduled before scheduling a new one.
It's because you are running your code once with one hour logic.
And then you are changing logic for two hour logic.
So basically both notification is triggering.
Either delete the app or previously scheduled notifications or change the identifier.
I have an app which uses UNLocationNotificationTrigger to deliver notification based on user's location. When I'm testing my app sometimes it registers that user entered specific region, but doesn't deliver notification on entering region. Other times it works perfectly but I was wondering why this doesn't work every time. Does anyone else have similar problem? I would appreciate if someone could give a short explanation on this problem :)
This is the piece of code for registering notification:
let notification = UNMutableNotificationContent()
notification.title = "Notification title"
notification.subtitle = "Notification subtitle"
notification.body = "Notification body"
let notificationTrigger = UNLocationNotificationTrigger(region: enteredRegion, repeats: true)
let notificationRequest = UNNotificationRequest(identifier: "id12494", content: notification, trigger: notificationTrigger)
UNUserNotificationCenter.current().add(notificationRequest, withCompletionHandler: nil)
I want to clear remote notifications so they don't add up in the Notification Center (like when you get a video call in WhatsApp or Messenger, only the last notification is displayed).
I tried to call (in didReceiveRemoteNotification):
let center = UNUserNotificationCenter.current()
center.removeDeliveredNotifications(withIdentifiers: ["notification_identifier"])
But it gets called only if the app is active. How can I do this if the app is in another state?
Thanks for your help.
After some research and thanks to Paulw1's answer, I found out there are two ways of doing this:
Remote only
Notifications can be collapsed remotely, you only have to send the notification with apns-collapse-id as a request header. Please note that it's only supported in HTTP/2 though. More information here.
Silent remote + local notification
The other way consists in sending a silent remote notification, with this kind of payload:
{
"type": "notification_type",
"aps" : {
"content-available": 1
}
}
It will call didReceiveRemoteNotification even if the app's state is inactive or background. Then, I create a local notification request (needs using UserNotifications, available from iOS10) :
let content = UNMutableNotificationContent()
content.body = "Notification message"
let trigger = UNTimeIntervalNotificationTrigger(timeInterval: 0.25, repeats: false)
let request = UNNotificationRequest(identifier: "identifierToUpdate", content: content, trigger: trigger)
self.center.add(request, withCompletionHandler: nil)
The key to update the previous notification is to use the same request identifier.
In our app, the user will clock-in when he starts his work. If the user forgets to clock-out, we will have to automatically clock him out after 24 hours from the clock-in time. The app might not be in the active/background state for such a long time. It might be terminated. So our idea is to post a local notification through which will execute the code in the background to clock him out. This notification has to be a silent notification. But our understanding from the research is that local notifications cannot be silent. So is there any other way we could achieve this? Or can we actually schedule a silent local notification?
class func generateLocalNotificationWith(timeInterval : TimeInterval, title : String, message : String, mobileTimeClockId: Int)
{
UNUserNotificationCenter.current().removeAllPendingNotificationRequests()
let content = UNMutableNotificationContent()
//adding title, subtitle, body and badge
content.title = title
content.body = message
let userInfoDictionary = ["badge":"0","content-available": "1"]
let dict = ["aps": userInfoDictionary, "MobileTimeClockId": mobileTimeClockId] as [String : Any]
content.userInfo = dict
//getting the notification trigger
let trigger = UNTimeIntervalNotificationTrigger(timeInterval: timeInterval, repeats: false)
//getting the notification request
let request = UNNotificationRequest(identifier: "SimplifiedIOSNotification", content: content, trigger: trigger)
//adding the notification to notification center
UNUserNotificationCenter.current().add(request, withCompletionHandler: nil)
}
If you want a notification to be silent and do background work it has to be a push notification. A local notification can't wake your app without some user interaction.
The best way to do what you want is to use Core Location region monitoring to wake your app when the user physically leaves their workplace. Region monitoring can wake your app silently in the background and let you do some work. The problem is that it's not 100% assured that it will be triggered and the user will need to accept background location permissions.
I'm doing an app in Swift 3 for iOS 10. I have done an UNNotificationContent to simulate a call in my app but it disappears approximately five seconds after being launched. I need to keep it more seconds, while the "calling" is in process. I want to keep the local notification until I call the removeAllPendingNotificationRequests method. Can I do it?
This is my code now:
let content = UNMutableNotificationContent()
content.body = "\(userName) is calling..."
content.sound = UNNotificationSound(named: "sound_call.wav")
content.badge = 1
let request = UNNotificationRequest(identifier: "notification", content: content, trigger: nil)
UNUserNotificationCenter.current().add(request)
Thanks!
There's no way to control how long the notification stays on the screen. That's controlled by the system.