[Bug] Android: Updating notification channels result in `ArgumentException`

[Bludator]

Description

The documented behavior is: If one creating a notification channel with existing ID the channels gets updated.

Now it results in

**System.ArgumentException:** 'CreateNotificationChannels failed: notificationChannelRequests contains NotificationChannelRequest with duplicate ChannelId: ["verification", "chat"] (Parameter 'notificationChannelRequests')'

The culprit is here. It merges new and existing channels next statement EnsureNotificationChannelRequests(...) checks for duplicates.

Basic Information

• Version with issue: latest one (it is in the develop branch)

[Bludator]

I think that simple:

.Where(c => !notificationChannelRequests.Any(newChannel => c == newChannel.ChannelId))

would fix it. -> We need to filter out existing channels that will get updated.

[thomasgalliker]

Thanks for reporting this. Maybe the interface INotificationChannels is a bit misleading.

• CreateNotificationChannels: Checks if the requested new notification channels already exist.
• SetNotificationChannels: Overwrites all existing notification channels. (I prefer to use this method at startup in order to have a defined set of notification channels available - I also use SetNotificationChannels if the language of the app is changed; SetNotificationChannels recreates notification channel name, description, etc...).

Does this help? Was it just a misleading method name or do you think there is still something wrong with CreateNotificationChannels?

[Bludator]

Oh I missed that method. It makes much more sense like this. 👍

Then my only problem is with this comment which is not true. I think, I was also misslead by android native/java api where creating and updating is done with the same method. So I would maybe even go beyond just deleting the remark and mention the SetNotificationChannels.

[thomasgalliker]

You're absolutely right, the comment is wrong. I'll check all comments. Let's keep this issue open until the fix is deployed.
Let me know if you come across any issues with SetNotificationChannels 👍🏻