I am creating an IOS application that makes use of PUSH notifications. When I send a PN, I send data to my application. IF my app is not active, I can then click the notification in the notification center to update the data in the app. However, IF I do not click the notification and I just resume the app via the launch screen, the app does not update correctly. Is there a way to update the apps pending notifications even if I don't press the notification center button and I just resume the app from the launch icon?
I have been scouring the internet with no luck. I have also tried to put the notification in a NSMUtable Array in the application delegate with no luck.
thank you in advance.
Without you having a list of notifications that the app can download from the server you won't have a consistent solution so that is the best bet.
If you turned on background fetch for your notifications then the app could maintain a list of the received notifications, but this approach would fail for any notifications coming in after the user had force quit the app.
Related
I have a chat application, developed on the Xamarin.Forms platform, in which users can chat with each other. I have managed c# code and UI both in the shared project.
I have been facing problem since long in iOS platform. When the iOS app is running on screen, having foreground mode then the app can successfully receive a message which has been send by another user. When the app is running in the background mode and someone sends a message, I want to notify the user by using local notification (No Push remote notification - Because I think as my app is already running in minimized mode there is no need to wake up the app by implementing Push notification). Even I have implemented local notification successfully but the problem is,
When the iOS application heads to the background mode, the main thread (task) is paused so, when some user sends a message the app is not able to execute the code (when app is minimized) so that it won’t be able to show the local notification. But when the application is brought back to the foreground the thread/task get resumed and then ie shows up the local notification and also the message.
I already have selected the "Background fetch" property under Background Modes in Info.plist. I have also added below the line in my FinishedLaunching method
UIApplication.SharedApplication.SetMinimumBackgroundFetchInterval(UIApplication.BackgroundFetchIntervalMinimum);
I have already worked and implemented code from below links, but didn’t worked for me.
https://learn.microsoft.com/en-us/xamarin/ios/app-fundamentals/backgrounding/ios-backgrounding-techniques/
https://learn.microsoft.com/en-us/xamarin/ios/app-fundamentals/backgrounding/ios-backgrounding-techniques/ios-backgrounding-with-tasks#performing-tasks-during-didenterbackground
Xamarin forms background tasks run only when app is open on ios
https://arteksoftware.com/backgrounding-with-xamarin-forms/
When an iOS application goes to the background, are lengthy tasks paused?
How to perform a simple background task on Xamarin iOS
https://learn.microsoft.com/en-us/xamarin/ios/app-fundamentals/backgrounding/ios-backgrounding-techniques/ios-backgrounding-with-tasks#creating-background-safe-tasks
https://learn.microsoft.com/en-us/xamarin/ios/app-fundamentals/backgrounding/
I think my issue is relate to iOS Background processing, So, does anyone has idea what to do, to execute the code when app is already in minimized mode?
Generally speaking, backgrounding is very restricted on iOS. If your app is in a certain category (e.g. Navigation, Music) you'd get extended backgrounding capabilities, but I don't believe that chat apps do. More specifically, Background Fetch is not really suitable for your problem. It is called on an irregular basis to fetch contents to be cached within your app in order to make showing contents to your users faster. Background fetch intervals may vary from 15 min to several hours (not sure about the latter).
What you need is remote notifications.
Remote notifications (also known as push notifications) let you push small amounts of data to devices on which your app is installed, even when your app isn't running.
Remote notifications are brokered via a priviliged service (Apple Push Notification service - APNs) to Apple devices and delivered in a timely manner (seconds rather than minutes or hours). Usually you'd want to keep the payload as little as possible (just send the chat ID for example) and let the app fetch its data when it's notified.
Speaking in terms of a chat application, your chat server would send the remote notification to the APNs whenever a user sends a message to the chat. The app would be notified, fetch additional data and then display the notification to the user. If the notification is tapped, the user would be taken to the chat window for the respective chat.
Please note that your app has to be registered with APNs, otherwise remote notifications won't work.
When app is not running (terminated NOT in background) and a remote push notifications is received, is there any way to inform the app about it so that the app can update something locally such as simple int counter?
I want to store something so that when the app is launched the next time, app knows that notification was received when app wasn't running and something needs to be done.
If user launches an app by tapping on a notification, obviously the app is notified about it through AppDelegate methods but these methods are never called if user launches an app by tapping on the app's icon.
To be aware of notification when user launches app by tapping on icon, i need some way to let app know that notification was received when app was in background.
There is no way you can achieve this with simple push notifications.
According to apple docs if the user has manually killed your application by swiping it out of memory, your app will never be started in the background to process data until after the user chooses to launch it again.
One solution to this problem is using VOIP push.
According to apple docs -
Your app is automatically relaunched if it’s not running when a VoIP
push is received.
But you need a strong reason for using it and apple may ask that before approving your app on the app store.
To read more about VOIP push please go through this doc - https://developer.apple.com/library/content/documentation/Performance/Conceptual/EnergyGuide-iOS/OptimizeVoIP.html
You can also be used the "Silent Push Notifications".Which are confirming that their is something available on the server, which you need to download to your app,The payload format of the Silent push notification is like
{ content-available:1 }
The Best part of the silent notification is that they do not notify the iPhone user
Here 1 is for their is something available to download from the server.
here below i have attached the apple's silent notification slide.
Your App is getting Refresh in the Background.
a simple question: is it possible to get a message, notification or similar when the internet connection is available when app is killed or not running?
For my purpose, I need a way to synchronize all my notifications because APNs can send only the last message.
EDIT:
I'm wondering how some apps (e.g. whatsapp) are able to sync their notifications when the internet connection is up. If I kill whatsapp, I can receive multiple notification when internet connection is reachable, but the APNS server provides only last message and, for this case, I'm not able to send silent notification. If I should develop a chat application, what are the best practices to work with Apple notifications?
If you send a push notification with a title, text, sound and/or badge property while the app is suspended (was killed / force closed), the device will still receive it, e.g. will show the text as a notification, play a sound and/or change the badge count.
However, your app won't be launched or woken up in the background in this case, so you have no way to handle the notification before the user taps on it. (See this question:
Will iOS launch my app into the background if it was force-quit by the user?)
So if the app was force closed by the user, your only option is to send a notification to be displayed as it is and if the device is offline, only the last notification will be received and displayed by the device.
For more control, you could use silent push notifications to implement "push-to-sync". In this case, the push notification only signals that there is new data to be fetched. The app (if not force closed) loads the data from the server then and triggers local notifications with the right data in the right order. But this won't work, if the app was force closed.
Apple push notifications have a lot of restrictions, so you won't be able to implement a perfect solution. In my opinion, it's fine if the user gets only the last notification when the device gets online after being offline for a while. At least he is informed that there is a new message and after opening the app, he can see the other new messages too. For the "push-to-sync" scenario, I would say that the user has no right to expect that the app works as desired, if he force-quits it.
Push notifications were never intended to be used in the way they are used by a lot of apps by now. E.g. they shouldn't contain sensitive data such as a chat message. They were intended to inform the user that there is new data for the app, so he can launch it to see the new data. E.g. instead of sending the actual chat message text a push notification should just contain the text "You have a new message". Then, you don't have the problem you described. Of course this is a terrible solution in terms of usability.
I cant find a clear answer about this in the Titanium documentation. Is it possible to directly respond to a push notification while the app is killed ?
I know that the callback is called when you open the app trough the push notification. but is there a way to respond when the app is opened manually ?
I tried to use remote-notification as UIBackgroundModes, but this only helps for paused apps.
My goal is to show the push notification in a in-app message center.
You should never rely on push notifications to deliver you payloads, they are too limited for that. If the user receives 5 push notifications and opens the app via the app icon, you will never receive any of the payloads. If he opens the app via one of those notifications you will only receive that payload.
You could use silentpush:
http://docs.appcelerator.com/platform/latest/#!/guide/iOS_Background_Services-section-37539664_iOSBackgroundServices-SilentPush
But the app should always query a back-end to get the actual data. That's how WhatsApp does it as well, as you can see when you open it via a notification it will then still fetch the message(s) form the server.
I’m building an app which handles notifications pushed from Parse, and trying to create a notification history function. I’ve enabled the background modes successfully, so when the app is running in the background, the app can get the payload well via application:didReceiveRemoteNotification:fetchCompletionHandler even the banner/alert is not tapped. However, when force-quit / swipe up to kill the app, application:didReceiveRemoteNotification:fetchCompletionHandler is not called.
Is there any method to implement for getting the push notification payload when the app is killed without tapping the banner/alert? Thank you in advance!
You can't get a notification's payload if your app is killed.
In most cases, the system does not relaunch apps after they are force
quit by the user. One exception is location apps, which in iOS 8 and
later are relaunched after being force quit by the user. In other
cases, though, the user must launch the app explicitly or reboot the
device before the app can be launched automatically into the
background by the system. When password protection is enabled on the
device, the system does not launch an app in the background before the
user first unlocks the device. -
Understanding When Your App Gets Launched into the Background
Anyway, push notifications are not reliable.
It means that you can not be sure that they will ever be delivered.
If you want to keep a "notification history" list, do it server-side and fetch it in-app (in a totally not push related way).
Each time you send a push notification, keep it's content in database, like any object. Then when the user opens the history list, fetch the list like any other parse object.