Hi all, I have a weird bug with CMP and Room. I ha...

# compose

[Alexandru Caraus]

Hi all, I have a weird bug with CMP and Room. I have two screens A and B. ViewModelA is subscribed to a room table through flow on init. After starting the app i go to screen B, modify the table, go back to screen A, everything works as expected A reacts to changes in the table done in B. Now that stops working after screen rotation. I worked around it by recollecting on rotation, but this is weird since vm is the same and initial collection job is active and fine. Does anyone have an idea?

[Sean Proctor]

It's a bit hard to guess without seeing what you're actually doing. Can you make a simple reproducer? I'm guessing hitting back re-uses the same observer, rotating causes a configuration change which means you recreate the observer in your UI code, and however you're doing things in the VM fails with the second observer.

[Alexandru Caraus]

Sure, here is the viewmodel https://github.com/alexandrucaraus/kmp-sample-arch/blob/main/features/notes/src/commonMain/kotlin/eu/caraus/kmp/notes/presentation/list/NoteListViewModel.kt

[Alexandru Caraus]

And the subscription of viewmodel https://github.com/alexandrucaraus/kmp-sample-arch/blob/main/features/notes/src/commonMain/kotlin/eu/caraus/kmp/notes/presentation/list/NoteListRoute.kt

[Alexandru Caraus]

Ah, found the issue, it was about Dependency Injection setup, the two viewmodels where supposed to use the same singleton as dependency, but the singleton was not a singleton, was a new instance on rotation.

[Sean Proctor]

Ah, makes sense. DI can complicate things. I couldn't find anything just by reading.