[Enhancement] .NET 9 support

[konoshchenko]

I’m currently using .NET 9 and MAUI 9 for my production project and would love to continue using this great plugin for Firebase Push Notifications.

At the moment, it seems that the latest pre-release version (3.2.2-pre) does not fully support .NET 9 / MAUI 9, and the token initialization either fails or remains null. Are there any plans for a stable release with .NET 9 support?

[jkuek]

A note to say, I am on .NET 9 and have not experienced the issue described here. While I am still working through some issues, I am able to get an FCM token and receive push notifications.

I would have liked the example app to be in .NET 9 however, as I had to downgrade a bunch of my libraries in order to modify the sample app for testing.

[thomasgalliker]

As far as I know, this library should also work in .NET 9 MAUI apps. It's compiled against/with net8.0, net8.0-android and net8.0-ios. It should be possible to run a net8.0 library in a net9.0 project. Let me know if I'm on the wrong path.

[jkuek]

I can't comment to the original poster's concerns, but I will reiterate that I am using the library in my .NET MAUI 9 app and receiving push notifications on iOS and Android.

There's no issue using .NET 8 libraries with .NET 9 projects.

[AlleSchonWeg]

I also have the plugin working with .Net 9. One difference is between 8 and 9 is aot/trimming. I had some problems with newtonsoft.json in my app and completly replaced newtonsoft with System.Text.Json.
This library also uses newtonsoft. Perhaps this could be a problem.

[thomasgalliker]

@konoshchenko the token initialization failure you describe: Does it happen on Android or on iOS? Can you explain when it happens? I guess the .NET version is irrelevant in this case - but it's just a guess.

[jkuek]

I did have another thought, I am running with AutoInitEnabled explicitly set to true.

When I was first playing with the library, trying to resolve other issues, I was possibly seeing some variation between iOS and Android when it was false. IIRC the Token property was set on one OS and null on the other.

Take this as purely anecdotal (my memory might be faulty or my experience might be entangled with some other bug I was investigating)

[thomasgalliker]

There is a new pre-release (starting 4.0.18-pre) which now also targets net9.0, net9.0-ios and net9.0-android explicitly. The old net7.0-* target framework monikers have been removed.

On top of that, the sample app in this branch #138 has been migrated to .net9.0 too.

[sgreifeneder]

@thomasgalliker
After upgrading to .NET9, I don't get FCM tokens on iOS anymore.
[FirebaseMessaging][I-FCM002022] Declining request for FCM Token since no APNS Token specified
Android seems to work, and also before upgrading to .NET9 everything was working as expected for Android+iOS.

I tried with the installed version (v3.0.17), latest stable (v3.2.11) and latest (v4.0.23-pre).

I also checked your sample, and adapted the following in my code:

• Call options.AutoInitEnabled = false; as first thing in UseFirebasePushNotifications()
• Added callbacks to AppDelegate.cs
• Added remote-notification to UIBackgroundModes and FirebaseAppDelegateProxyEnabled (set to false) in Info.plist

[geekywarrior]

I was forced to update to.NET 9 after updating my workloads. Unfortunately I'm having similar issues with some added information.

1. I have an iPad on iOS version 17, everything works great still
2. On my iPhone simulator set to version 18.5, I receive a FCM token but I do not receive any push notifications
3. On my iPhone simulator set to version 26, I do not receive a FCM token at all

I believe I'm running plugin version 4.0, I'm actually running a fork of this project as I needed the notification channel fixes in my PR #142

[geekywarrior]

Update with some strange behavior, I have a iPhone with 18.6.2, works fine without doing any changes.
The simulator on 18.5 was not working until I went to Entitlements.plist and checked the box for Push Notifications.
Now that works fine. You would think that always has to be checked, strange how it works fine on .NET 8 or physical devices without it.

Software 26 still not successfully registering for a token. Even stranger it gets through RegisterForPushNotificationsAsync without any errors or exceptions.

Edit: This might be a bug in xcode on the simulator: https://developer.apple.com/forums/thread/795433

[AlleSchonWeg]

Something is broken with iOS 26, simulators and latest Xcode: firebase/firebase-ios-sdk#15315
I think this is not a plugin bug.