Hello, I'm trying to use KodeinDI alongside FlowMV...

# kodein

[kluck]

Hello, I'm trying to use KodeinDI alongside FlowMVI (https://github.com/respawn-app/flowMVI). In their sample, they provide extension functions for injecting the view model via Koin, and I tried to the best of my capability to reproduce what they made. Here's their code:

@Composable
inline fun <reified T : Container<S, I, A>, S : MVIState, I : MVIIntent, A : MVIAction> storeViewModel(
    viewModelStoreOwner: ViewModelStoreOwner = checkNotNull(LocalViewModelStoreOwner.current) {
        "No ViewModelStoreOwner was provided via LocalViewModelStoreOwner"
    },
    key: String? = null,
    extras: CreationExtras = defaultExtras(viewModelStoreOwner),
    scope: Scope = getKoinScope(),
    noinline parameters: ParametersDefinition? = null,
): StoreViewModel<S, I, A> = getViewModel(qualifier<T>(), viewModelStoreOwner, key, extras, scope, parameters) // -> This is a koin method

What I came up with:

@Composable
fun <S : MVIState, I : MVIIntent, A : MVIAction> storeViewModel(
    viewModelStoreOwner: ViewModelStoreOwner = checkNotNull(LocalViewModelStoreOwner.current) {
        "No ViewModelStoreOwner was provided via LocalViewModelStoreOwner"
    },
    tag: Any? = null,
): StoreViewModel<S, I, A> = with(localDI()) {
    getViewModel(viewModelStoreOwner = viewModelStoreOwner, tag = tag, di = this)
}

@Composable
inline fun <reified T : ViewModel> getViewModel(
    viewModelStoreOwner: ViewModelStoreOwner,
    tag: Any?,
    di: DIAware,
): T = resolveViewModel(T::class, viewModelStoreOwner, tag, di)


inline fun <reified T : ViewModel> resolveViewModel(
    vmClass: KClass<T>,
    viewModelStoreOwner: ViewModelStoreOwner,
    tag: Any?,
    di: DIAware,
): T {
    val factory = di.viewModelFactory(tag)
    val provider = ViewModelProvider(
        store = viewModelStoreOwner.viewModelStore,
        factory = factory,
        defaultCreationExtras = defaultExtras(viewModelStoreOwner),
    )
    return provider[vmClass.java]
}


fun DIAware.viewModelFactory(tag: Any?): ViewModelProvider.Factory = object : ViewModelProvider.Factory {
    override fun <T : ViewModel> create(modelClass: Class<T>, extras: CreationExtras): T =
        di.direct.Instance(type = erased(modelClass), tag = tag)
}

It kind-of works, as I manage to retrieve my first store view model (val store = storeViewModel<MainState, MainIntent, MainAction>(tag = MAIN_STORE_TAG)). But as soon as I try injecting a second one, it retrieves the first one… I use tags to distinguish the two, but I guess there is some erasing stuff that I don't get correctly… Any idea what I could change in my code?
Thanks!

[kluck]

Hmm, I found a solution, I used provider[tag, vmClass.java] instead of provider[vmClass.java] . Not sure if it's the best solution though…

[romainbsl]

Did you get a look at or Jetpack Compose implementation?
https://github.com/kosi-libs/Kodein/blob/master/framework/compose/kodein-di-framework-android-x-compose/src/main/kotlin/org/kodein/di/compose/android/viewModel.kt

[kluck]

Yes I did, that's where I found this usage of provider[tag, vmClass.java] , thanks!

[romainbsl]

Cool 👍 !
I’m curious to know your experience with FlowMVI. It seems there are many MVI/Redux implementations available for KMP.

[kluck]

Just testing it for now, but it looks promising, I like the modularity of it by making everything as they call it "plugins". The fact that it's not intertwined with the Android framework makes it easier to test and control. Definitely worth a try!