Hi <@UHAJKUSTU>, all good things are three so here is another question. More in thread:

# decompose

[Jan]

Hi @Arkadii Ivanov, all good things are three so here is another question. More in thread:

[Jan]

I have a RootComponent with a SlotNavigation

[Jan]

Within that RootComponent I have a flow to determine the state of the app and I start listining to it within the init of RootComponent

[Jan]

An initial slot is activated und slotNavigation persistent is set to true

[Jan]

After orientation change occured the flow is somehow broken due I do not get events anymore

[Jan]

Its working again if I explicit dismiss the last active config in my slot navigation on destroy

[Jan]

I have the feeling that the slotChild does somehow not recognize that a new component was created due orientation change and probably leaks

[Jan]

My RootComponent looks something like this:

[Jan]

class RootComponent(
    private val componentContext: ComponentContext,
    private val getRootState: GetRootStateUsecase
) : ComponentContext by componentContext, KoinComponent {
private val slotNavigation = SlotNavigation<SlotConfig>()

    private val _slot = childSlot(
        source = slotNavigation,
        initialConfiguration = { SlotConfig.Home }
    ) { config, childComponentContext ->
        when (config) {
            else ->
                HomeComponent(
                    componentContext = childComponentContext,
                    componentViewModel = childComponentContext.instanceKeeper.getOrCreate {
                        getKoin().get()
                    },
                    headerViewModel = childComponentContext.instanceKeeper.getOrCreate {
                        getKoin().get()
                    }
                )
        }
    }

    val slot: Value<ChildSlot<*, *>> = _slot

    private val componentScope = coroutineScope(Dispatchers.Main + SupervisorJob())

    init {
        lifecycle.doOnDestroy {
            //slotNavigation.dismiss()
        }

        componentScope.launch {
            getRootState().collect { config ->
                println("RootComponent received new state config: $config")

            }
        }
    }
}

[Jan]

is that correct that I have to dismiss it manually even though I set persitent = true on my slotNavigation?

[Arkadii Ivanov]

The "persistent" flag means that the slot will stay active on configuration change. So you usually don't need to manually close the slot on destroy.

[Jan]

Yes, but unfortunately if I don't do so my flow breaks

[Arkadii Ivanov]

Can you show more code? What is getRootState?

[Jan]

Its just a UseCase wich links to a repository and returns a flow:

class GetRootStateUsecase(
    private val rootStateRepository: RootStateRepository
) {
    suspend operator fun invoke(): Flow<RootComponent.SlotConfig> = rootStateRepository.getState()
}

interface RootStateRepository {
    suspend fun getState(): Flow<RootComponent.SlotConfig>
}

class RootStateRepositoryImpl(
    private val ioDispatcher: CoroutineDispatcher,
    private val venueRepository: VenueRepository,
    private val userRepository: UserRepository
) : RootStateRepository {

    override suspend fun getState(): Flow<RootComponent.SlotConfig> = flow {
        val selectedVenueFlow = venueRepository.getSelectedVenue()
        val selectedUserFlow = userRepository.getSelectedUser()
        selectedVenueFlow.combine(selectedUserFlow) { selectedVenue, selectedUser ->
            State(
                venue = selectedVenue,
                user = selectedUser
            )
        }.distinctUntilChanged().collect {
            if (it.venue == null) {
                emit(RootComponent.SlotConfig.Inventory)
            } else if (it.user == null) {
                emit(RootComponent.SlotConfig.Login)
            } else {
                emit(RootComponent.SlotConfig.Dashboard)
            }
        }
    }.flowOn(ioDispatcher)
}

private data class State(
    val venue: Venue?,
    val user: User?
)

[Jan]

If I use a stack-navigation instead of slot-navigation it seems to work correctly

[Arkadii Ivanov]

Thanks. Based on the code I can't say what's wrong. I recommend to create a minimal reproducer so I could check.

[Jan]

ok, I will. It feels like that slot within the composable is somehow not in sync anymore

[Arkadii Ivanov]

I suspect you have a leak in either componentViewModel or headerViewModel

[Jan]

probably but I thing I checked that

[Arkadii Ivanov]

You may also be interested in retained components: https://arkivanov.github.io/Decompose/component/instance-retaining/#retained-components-since-v210-alpha-03

[Arkadii Ivanov]

But I would rather find the leak

[Jan]

hehe

[Jan]

me too 😉

[Jan]

ok, I think I found my leak

[Jan]

sorry for bothering you

[Arkadii Ivanov]

Yay!

[Jan]

ok, it was not even a leak!

[Jan]

I stopped started/stopped koin during orientation change (oncreate/ondestroy in activity) and therefore my viewmodels broke

[Arkadii Ivanov]

Thanks for sharing! Koin was my second suspect. 😀