My requirement is prevent remote notification from being display.
I can handler this if app is in foreground or background in following methods:
func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any]) {
//logic hide notification here
}
public func userNotificationCenter(_ center: UNUserNotificationCenter,
willPresent notification: UNNotification,
withCompletionHandler completionHandler: #escaping (UNNotificationPresentationOptions) -> Void) {
//logic hide notification here
}
When app is being killed, I'm trying to handler logic in UNNotificationServiceExtension but it did not work:
override func didReceive(_ request: UNNotificationRequest, withContentHandler contentHandler: #escaping (UNNotificationContent) -> Void) {
// logic hide notification here
}
I've read this article: Is it possible to prevent a remote notification from being displayed?
It said that Apple not allow to do this, is this correct?
Yes, it's correct.
You cannot catch a remote notification and hide it. The best way to not receive remote notifications is to say no to the permission. If your server send remote notifications you can configure it not to send notifications when you does not want.
Another way to send notifications and not show them is to send "silent notification". It allows you to receive the notification, get its content and do what you want (you have only 30s). I thinks, you can send silent notifications, check content and send a local notification if it needs to, but I'm not sure.
Are you attempting to remove notifications completely? (foreground AND background?)
If that is the case then you should ask your back-end service to send you a silent notification instead of a normal one. you shouldn't be handling that yourself.
Related
I have implemented push notification for ios10. Tapping on the notification alert would trigger "didReceive" delegate, were i save the notification in coredata or silent notification if i m in foreground. The problem is if i receive a stack of notification in background and When i bring my app to foreground from background, Is there a possibility to call "didReceive" delegate or any other push notification delegate were i could sync my items to coredata.
Note
I don't want to sync(didReceive or any delegate) the items in background using silent notification nor tapping on the alert. It should sync automatically the stack of push notification when i bring the app to foreground
func handleInboxNotification(didReceiveRemoteNotification userInfo: [AnyHashable: Any]) {
if let inboxValue = userInfo["inbox"] as? String, let value = inboxValue.boolValue(), value {
let mappedMessage = MessageCenterSDK.shared.constructReorderedDictionary(userInfo: userInfo)
MessageCenterDataManager.shared.synchronize(messages: mappedMessage)
messageCenterDelegate?.didFindNewMessages(hasNewMessages: true)
}
}
func userNotificationCenter(_ center: UNUserNotificationCenter,
didReceive response: UNNotificationResponse,
withCompletionHandler completionHandler: #escaping () -> Void) {
/// Handle outbound remote
handleInboxNotification(didReceiveRemoteNotification: response.notification.request.content.userInfo)
completionHandler()
}
I was facing the same issue, but my target was for iOS 13 & I'm using BGTaskScheduler to fetch data from the server in the background as well in terminated state.
I too want to trigger the notification when the app is in background. But not tapped but that seems to be not possible so we have changed our implementation by enabling background mode and it worked for me.
Hope it also helps.
For more reference on BGTaskScheduler, https://developer.apple.com/documentation/backgroundtasks/bgtaskscheduler
you need to use willpresent delegate in appDelegate
func userNotificationCenter(_ center: UNUserNotificationCenter,
willPresent notification: UNNotification,
withCompletionHandler completionHandler: #escaping (UNNotificationPresentationOptions) -> Void) {
// Change this to your preferred presentation option
completionHandler([])
}
This delegate is called when a notification comes in foreground
When the server sends a silent notification, I want to check if the user is in the right state and then issue a local notification as a result if the user is in the right state or do nothing if the user is not in the right state.
Is this feasible?
Thank you!
If you send the push notification with "content-available": 1 it will be a silent push (see Apple's local and remote notification guide).
You then want to conditionally schedule a local notification with UNUserNotificationCenter.current().add() and implement the delegate methods for UNUserNotificationCenterDelegate.
It's not good idea.
The system treats background notifications as low-priority.
proof: https://developer.apple.com/documentation/usernotifications/setting_up_a_remote_notification_server/pushing_background_updates_to_your_app
So background notification is not for you case.
If you don't want show notification for some cases, you just in
implementation method of UNUserNotificationCenterDelegate don't call completion handler:
func userNotificationCenter(_ center: UNUserNotificationCenter,
willPresent notification: UNNotification,
withCompletionHandler completionHandler: #escaping (UNNotificationPresentationOptions) -> Void) {
guard self.shouldShowNotification(notification) else { return } // don't call completion handler if we're don't want to show push
completionHandler(.alert)
}
func shouldShowNotification(_ notification: UNNotification) -> Bool {
if ... {
return true
} else {
return false
}
}
I have a messaging app, which gets data from server through push notification.
In the following image, you can see the process and also check where it gets faulted:
I have researched a lot about this problem but not getting a universal solution.
One solution I get is to use silent notification , discussed Here , to get data before it is shown and save it. But I didn't find how to show notification from app delegate once I received silent notification.
Kindly correct me if I am conceptually wrong somewhere.
Update:
One of problem is that the application:didReceiveRemoteNotification:fetchCompletionHandler: is only called when
app is in foreground
user clicks the notification
But when user doesn't click the notification, application:didReceiveRemoteNotification:fetchCompletionHandler: is not called, and I can't find a way to save the data, that is present in notification.
Your question is "To get data from Remote notification while the App is in foreground" if im correct, You can use these two methods to get data from Remote notifications for background and foreground app modes.
// Notification will present call back
#available(iOS 10.0, *)
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: #escaping (UNNotificationPresentationOptions) -> Void) {
completionHandler([.alert, .sound, .badge])
// Handle your data here
print("Notification data: \(notification.request.content.userInfo)")
}
#available(iOS 10.0, *)
// Notification interaction response call back
func userNotificationCenter(_ center: UNUserNotificationCenter,
didReceive response: UNNotificationResponse,
withCompletionHandler completionHandler: #escaping () -> Void) {
// Handle your data here
print("Notification data: \(response.notification.request.content.userInfo)")
}
There are two cases:
Background
Closed State
If the app is in Background State, you have to enable Background Fetch, then this method will be called when the app is in Background application:didReceiveRemoteNotification:fetchCompletionHandler:
When the app is closed or killed by the user the above method not gonna work, for that you can use the VoIP technique.
didReceiveIncomingPushWithPayload method will be called whenever Remote Notification arrives
You can find more details about VoIP here
I know similar questions have been asked many times. But it is still very confusing to me after reading those threads, especially after UNUserNotificationCenter is introduced in iOS 10.
The official documentation mentioned 3 methods where I can handle remote notifications:
Implement userNotificationCenter:willPresentNotification:withCompletionHandler: to handle a notification when the app is in foreground.
Implement userNotificationCenter:didReceiveNotificationResponse:withCompletionHandler: when the app is in background or not running.
But the documentation also mentioned: In iOS and tvOS, the system delivers the notification payload to the application:didReceiveRemoteNotification:fetchCompletionHandler: method of the app delegate.
So,
To handle a remote notification when app is in background/inactive, should I put my code in application delegate method in 3, or the notificationCenter delegate in 2? Since UNUserNotificationCenter is only available for iOS>10, should I write different code to handle each case?
About 1, it is only available after iOS 10. How can I handle remote notifications when app is running in foreground before iOS 10?
And, more confusing: In case the app is in background, when are the delegate methods called: when the notification message is received? or when the user taps the notification?
Related: iOS push notification: how to detect if the user tapped on notification when the app is in background?
iOS 10 and later:
1) userNotificationCenter willPresent notification: Generally used to decide what to do when user is already inside the app and a notification arrives. You could possibly trigger a remote notification inside the app. After the user taps on the remote notification, method 2 (didReceive response) gets called.
#available(iOS 10.0, *)
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: #escaping (_ options: UNNotificationPresentationOptions) -> Void) {
//Handle push from foreground
//When a notification arrives and your user is using the app, you can maybe notify user by showing a remote notification by doing this
completionHandler([.alert, .badge, .sound])
//To print notification payload:
print(notification.request.content.userInfo)
}
2) userNotificationCenter didReceive response: Generally used to redirect the user to a particular screen of the app after user taps on the notification.
#available(iOS 10.0, *)
func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: #escaping () -> Void) {
//Handle push from background or closed (or even in foreground)
//This method is called when user taps on a notification
//To print notification payload:
print(response.notification.request.content.userInfo)
}
Below iOS 10:
3) application didReceiveRemoteNotification:
func application(_ application: UIApplication, didReceiveRemoteNotification userInfo: [AnyHashable: Any],
fetchCompletionHandler completionHandler: #escaping (UIBackgroundFetchResult) -> Void) {
//To print notification payload
print(userInfo)
if #available(iOS 10.0, *) {
}
else {
//Handle remote notifications for devices below iOS 10
if application.applicationState == .active {
//app is currently in foreground
}
else if application.applicationState == .background {
//app is in background
}
else if application.applicationState == .inactive {
//app is transitioning from background to foreground (user taps notification)
}
}
}
4) application didFinishLaunchingWithOptions launchOptions: The only scenario which is left for devices below iOS 10 is when app is closed and user taps on the notification launching the app. You'll have to check the following method for this scenario.
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
//To print notification payload:
if let notification = launchOptions?[UIApplicationLaunchOptionsKey.remoteNotification] as? [AnyHashable: Any] {
print(notification)
}
}
LaunchOptions is a dictionary indicating the reason the app was
launched (if any). The contents of this dictionary may be empty in
situations where the user launched the app directly.
Now to answer your questions,
To handle a remote notification when app is in background/inactive, you'll have to add your code in method 2 (userNotificationCenter didReceive response) for devices with iOS 10 and above. Also, you'll have to use method 3 (application didReceiveRemoteNotification) for devices below iOS 10.
To handle remote notifications when app is running in foreground before iOS 10, use the method 3 active state.
In addition to the great answer by Ameya, I wanted to point out that userNotificationCenter:willPresent:notification does not get called if app is in background state.
My complete solution to handle all cases on iOS 10+ would be to also use application:didFinishLaunchingWithOptions:launchOptions, and check if in background state, and handle the notification there too. Your payload, however, now also needs to include the "content-available": 1 field).
I have been struggling with this problem for days and I have looked at every post about this and nothing works.
I am using FCM (Firebase Cloud Messaging). FCM talks directly to the app when in foreground, but it will use APNS when the app is in background.
I am trying to call a method everytime the app got notification by calling the method in the push notification's delegate function
I have these 2 delegate functions:
func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: #escaping () -> Void)
and
func userNotificationCenter(_ center: UNUserNotificationCenter, willPresent notification: UNNotification, withCompletionHandler completionHandler: #escaping (UNNotificationPresentationOptions) -> Void)
which does not get called in background, according to apple documentation.
I also have this function which I believe should get called in the background but it does not.
func application(_ application: UIApplication,didReceiveRemoteNotification userInfo: [AnyHashable: Any],fetchCompletionHandler completionHandler: #escaping (UIBackgroundFetchResult) -> Void)
I have all of these functions in ViewController
In background mode, I get banner notifications, but none of the delegate is called. Is there any way to make any of them work in the background, if not what should I do?
In addition I also get this error : <FIRMessaging/WARNING> FIRMessaging receiving notification in invalid state 2 in the log everytime I send a payload while the app is in the background.
Here is the payload that I send using postmate:
{
"priority":"high",
"notification":{
"sound": "default",
"badge": "1",
"title":"mytitle",
"body":"mybody",
"message":"Hello"
},
"content_available":true,
"to" : "/topics/myTopic"
}
I already turned on push notification in capabilities and checked push notification in background modes under capabilities.
I use Xcode 8 and have been testing on iphone 6 iOS 10.0.2
There can only be 1 delegate for a protocol.
In this case, I made APPDelegate and ViewController conform to UIApplicationDelegate. And only delegate functions in APPDelegate got called. That's why the one in ViewController is not called.
The solution would be just put didReceiveRemoteNotification in the AppDelegate.