Notification from background service

[avojacek]

Hi all,
how to correctly display notifications from background task as a Toast message or MessageBar?
I have some background tasks which are queued in background service, they are started from Blazor app. How can I display message to user using MessageBar or Toast? Is this even possible to do that. Is there way to display those only to user which started that job or even better to all who is using Blazor app at moment of completion that task?
My blazor App is server side no wasm.

Thank you a lot.
A.

[dvoituron]

You could use the Toast service or the Message service. Every time you will add a message, Blazor will send a SignalR message to the client to display your information.

If your process come from the "startup tasks", you should use the SplashScreen component.

[vnbaaij]

No need to apologize.

As Denis said. it is more a C#/Blazor thing. If the background service has 'access to' or can 'see' the service, then yes it can be injected.
But I don't think it will work because the background service probably runs on a different thread than the site/app itself. Not sure if it will be picked up. But you can just try it to find out, right.

[avojacek]

Yes, I will try, I tried to look into AddFluentUIComponents and MessageService is registered as scoped, so I thing it will not work. I have to find another solution.
Anyway thank you both.

[dvoituron]

In this case, don't call AddFluentUIComponents and check this method to create a similar one with your preferences. This is just an Helper method to inject these services.

[avojacek]

That's looks promising :-) I was scared to do that. I will look at that if I can register that as Singleton. Thank you a lot.

[avojacek]

Hm :-) no luck MessageService needs NavigationManager which is scoped and cannot be consumed by singleton. :-) But anyway thank you a lot. I will do that some other way.
It is realy usefull to look into source code :-)
Thank you both for your time.
Ales