Is it possible to scope a viewmodel to a navigation graph with navigation-compose?

# compose

[Jason Ankers]

Is it possible to scope a viewmodel to a navigation graph with navigation-compose?

[fmasa]

AmbientViewModelStoreOwner is scoped to NavBackEntry by default. But you can pass "parent" AmbientViewModelStoreOwner (the ambient value passed to given NavHost) as your own ambient.

[fmasa]

I pass Activity that way (using custom AmbientActivity) to scope few viewmodels that are used everywhere to Activity

[Jason Ankers]

Ok cool, so I think thats working. I’m using Hilt to inject some dependencies into my ViewModel, which fails now because I’m creating the ViewModel with a ViewModelProvider. I think I need to pass a ViewModelProvider.Factory but I’m not sure where to get it in compose. Previously in fragments I was using defaultViewModelProviderFactory , do you know if theres a substitute in compose?

Before compose I had this: https://developer.android.com/training/dependency-injection/hilt-jetpack#viewmodel-navigation

[fmasa]

Don't know about that. I use Koin right now 😕

[FunkyMuse]

If you're using navigation compose by default they're scoped to the navigation graph

[fmasa]

but only view models accessed via navGraphViewModels , right? AmbientViewModelStoreOwner (used by viewModel()) is NavBackStackEntry.

[Ian Lake]

This Wednesday will be a good day for you - new APIs in Navigation Compose are coming out to get the NavBackStackEntry of parent graphs as well as a new Hilt Navigation artifact which gives you access to a properly scoped Hilt ViewModelProvider.Factory

[Jason Ankers]

@Ian Lake Great news 😄