Hi! Are there any updates about Multiplatform?

# uniflow

[Davide C]

Hi! Are there any updates about Multiplatform?

[arnaud.giuliani]

Yes, intersting topic. Would be great to see how we would implement a LiveData store on iOS

[Davide C]

I'm on an early stage of learning multi-platform + declarative UI so probably there are some pitfalls in the prototipe i'm working on, nevertheless:
• This article shows a way to collect a StateFlow on iOS
• What I'm trying to achieve is a "shared view model"

//COMMON
expect abstract class AViewModel() {
    val viewModelScope: CoroutineScope
    protected open fun onCleared()
}
//ANDROID
actual abstract class AViewModel : ViewModel() {
    actual val viewModelScope: CoroutineScope = androidViewModelScope
    actual override fun onCleared() {
        super.onCleared()
    }
}
//iOS
actual abstract class AViewModel {
    actual val viewModelScope: CoroutineScope = CoroutineScope(SupervisorJob() + Dispatchers.Main.immediate)
    protected actual open fun onCleared() {
        viewModelScope.cancel()
    }
}

• At the moment i'm wrapping redux-kotlin with this "shared view model" exposing state via StateFlow, here's a (very) simple example

class LauncherViewModel(
    private val store: Store<AppState>,
) :
    AViewModel() {
    private val mutableStateFlow: MutableStateFlow<LauncherState> = MutableStateFlow(store.state.launcher)
    private val unsubscribe: StoreSubscription = store.subscribe {
        if (mutableStateFlow.value !== store.state.launcher)
            mutableStateFlow.value = store.state.launcher
    }

    val state: StateFlow<LauncherState> = mutableStateFlow

    override fun onCleared() {
        unsubscribe()
    }

    fun toggle() {
        store.dispatch(LauncherAction.ToggleLoading)
    }
}

and on Android side

@Composable
fun LauncherScreen(viewModel: LauncherViewModel = getViewModel()) {

    val state by remember(viewModel) { viewModel.state }.collectAsState()
    LauncherContent(state = state) {
        viewModel.toggle()
    }
}

@Composable
fun LauncherContent(state: LauncherState, onButtonClick: () -> Unit) {
    Column {
        Text(text = state.isLoading.toString())
        Button(onClick = onButtonClick) {
            Text(text = "Next")
        }
    }
}

I'd like to replace redux-kotlin with uniflow-kt which i find neat and concise, furhtermore with the "shared view model" it would be natural to extend DataFlow like AndroidDataFlow. Do you think it's feasible expose state and events via StateFlow (or other flows) rather than LiveData?