Hi there, congrats for the release of Koin 4.0.0 a...

# koin

[uli]

Hi there,
congrats for the release of Koin 4.0.0 and it’s great Kotlin/Compose multiplatform support.
I am currently looking into compose navigation and found koinNavViewModel were the only available piece of information on the whole internet is from the online documentation:

koinNavViewModel() - inject ViewModel instance + Navigation arguments data (if you are using Navigation API)

And from KDoc

Resolve ViewModel instance with Navigation NavBackStackEntry as extras parameters

I do not have the slightest idea what that might mean nor do I understand if both claims are the same. Well, I have ideas but none of them turned out to be what the method does.
Same questions has been asked before but just before the final answer the thread dies :-)
https://kotlinlang.slack.com/archives/C67HDJZ2N/p1680127134580369

Most surprising, comparing the source code of koinViewModel and koinNavViewModel I could not find any difference. Well koinViewModel has a default parameter of defaultExtras() while koinNavViewModel has a default parameter of defaultNavExtras . But those two are finnaly 100% identical.

Thanks for shedding any light on
1. Precondition: when and where can the method be used. A.k.a can ‘if you are using Navigation API’ be further specified. Do I need to be inside a NavGraphBuilder? Just in a composable that is nested in any nav graph?
2. What does it do? A.k.a can ‘instance with Navigation NavBackStackEntry as extras parameters’ be further specified. I expected a view model constructor parameter of type NavBackStackEntry to be automatically injected by koin. But that seems as if it does not work.
Maybe a small example would be really helpful.

[arnaud.giuliani]

ViewModel Nav is bringing NavBackStack arguments to your VM with the extras

[arnaud.giuliani]

those extras allow extraction to SavedStateBundle usage

[uli]

Thanks for the response. But this code is not in 4.0, is it?

[uli]

Well, it is. What I mean is, is the implementation from v4.0.0 of defaultNavExtras the expected implementation?

fun defaultNavExtras(viewModelStoreOwner: ViewModelStoreOwner): CreationExtras = when {
    viewModelStoreOwner is HasDefaultViewModelProviderFactory -> viewModelStoreOwner.defaultViewModelCreationExtras
    else -> CreationExtras.Empty
}

[arnaud.giuliani]

yes. NavBackStackEntry fall in 1st case automatically yes