Hi all I m talking with respect to Compose + Android + ViewModel i believe i m taking to the right channel I have have view model where certain flow observers are initialized in the init part of the view model Due to recomposition the init is getting called multiple times and events are being delivered to two different instance of viewmodel Ideally i assume there is only one view model in action I m not sure if i m doing anything wrong here ``` Composable fun KioskLoginScreen viewModel KioskLoginViewModel navigateToKioskActivate gt Unit navigateToKioskFailure gt Unit HiltViewModel class KioskLoginViewModel Inject constructor context Application private val printerDevice PrinterDevice init Timber i vm $this viewModelScope launch printerDevice onDeviceStateChange distinctUntilChanged collectLatest Timber i vm printer state $it when it PrintingAllowed gt isPrintingAllowed = true printerDevice requestDeviceData PrinterDeviceDataReq $ Date n ``` I can see that Printing Allowed is getting collected twice from two different instances

Hi all, I'm talking with respect to Compose + Android + ViewModel, i believe i'm taking to the right channel . I have have view model where certain flow observers are initialized, in the init { } part of the view model. Due to recomposition the init { } is getting called multiple times and events are being delivered to two different instance of viewmodel . Ideally i assume there is only one view model in action. I'm not sure if i'm doing anything wrong here.

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@Composable
fun KioskLoginScreen(
    viewModel: KioskLoginViewModel,
    navigateToKioskActivate: () -> Unit,
    navigateToKioskFailure: () -> Unit
) {  .... } 

@HiltViewModel
class KioskLoginViewModel @Inject constructor(
    context: Application,
    private val printerDevice: PrinterDevice,
) {
    init {
        Timber.i("vm $this")
        viewModelScope.launch {
            printerDevice.onDeviceStateChange.distinctUntilChanged().collectLatest {
                Timber.i("vm printer state $it")
                when (it) {
                    PrintingAllowed -> {
                        isPrintingAllowed = true
                        printerDevice.requestDeviceData(PrinterDeviceDataReq("${Date()}\n"))
                    }
                }
            }
        }
    }

I can see that Printing Allowed is getting collected twice from two different instances

🧵 1

is there any special treatment that we have to have with init { } block when using composable ?

cah

10/28/2023, 11:59 AM

Where are you actually creating your view model

althaf

10/28/2023, 2:03 PM

it is injected via hilt

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composable(kioskLoginRoute) {
    Timber.i("kioslogin route")
    KioskLoginScreen(
        hiltViewModel(),
        navigateToKioskActivate = {
            navigateToKioskActivate.invoke()
        },
        navigateToKioskFailure = {
            navigateToLoginFailure.invoke()
        }
    )
}