Hilt Navigation Compose и ViewModel ⇐ Android

[Anonymous]

Я пытался следовать примерам в документации по Android, но не смог реализовать навигацию с помощью Navigation Compose, ViewModel и Hilt. Никаких ошибок не возникает, и в NavigationScreen LaunchedERffect не запускается при генерации ViewModel.
Composables:

Код: Выделить всё

@HiltAndroidApp
class MyApplication : Application() {}

@Serializable
object NavScreen

@AndroidEntryPoint
class MainActivity : ComponentActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
enableEdgeToEdge()
setContent {
val navController = rememberNavController()

PhotosSyncTheme {
NavHost(
navController = navController,
startDestination = NavScreen
) {
composable { NavigationScreen(navController) }
composable { HomeScreen() }
composable { Settings() }
}
}
}
}
}

@Composable
fun NavigationScreen(navController: NavController) {
val navViewModel = hiltViewModel()

val navigationEvent by navViewModel.navigationEvents.collectAsState(initial = NavigationEvent.NavigateToHome)

LaunchedEffect(navigationEvent) {
Log.d("Navigation Screen", navigationEvent.toString())
navigationEvent.let { event ->
Log.d("Navigation Screen", event.toString())
when (event) {
is NavigationEvent.NavigateBack -> navController.popBackStack()
NavigationEvent.NavigateToHome -> navController.navigate(NavigationEvent.NavigateToHome)
NavigationEvent.NavigateToSettings -> navController.navigate(NavigationEvent.NavigateToSettings)
}
}
}
}

@OptIn(ExperimentalMaterial3Api::class)
@Composable
fun HomeScreen() {
val navViewModel = hiltViewModel()
var selectedItem by remember { mutableIntStateOf(0) }

Scaffold(
modifier = Modifier.fillMaxSize(),
topBar = {
TopAppBar(title = { Text("Photos Sync") }, actions = {
IconButton(onClick = {
navViewModel.navigateToSettings()
}) {
Icon(
imageVector = Icons.Filled.Settings,
contentDescription = "Settings icon"
)
}
})
}
)
{ }
}

@OptIn(ExperimentalMaterial3Api::class)
@Composable
fun Settings() {
val viewModel = hiltViewModel()

Scaffold(
modifier = Modifier.fillMaxSize(),
topBar = {
TopAppBarWithBack(title = "Definições")
}
)
{ }
}

ViewModel:

Код: Выделить всё

@HiltViewModel
class NavigationViewModel @Inject constructor() : ViewModel() {
private val _navigationEvents = MutableSharedFlow()
val navigationEvents: SharedFlow  = _navigationEvents.asSharedFlow()

fun navigateBack() {
viewModelScope.launch { _navigationEvents.emit(NavigationEvent.NavigateBack) }
}

fun navigateToHome() {
viewModelScope.launch { _navigationEvents.emit(NavigationEvent.NavigateToHome) }
}

fun navigateToSettings() {
viewModelScope.launch {
Log.d("Navigation ViewModel", "Emit Navigate To Settings")
try {
_navigationEvents.emit(NavigationEvent.NavigateToSettings)

} catch (e: Exception) {
Log.e("Navigation ViewModel", "Error emitting navigation event")
} finally {
Log.d("Navigation ViewModel", "done Emit Navigate To Settings")
}
}
}

fun navigateTo(event: NavigationEvent) {
viewModelScope.launch { _navigationEvents.emit(event) }
}

sealed class NavigationEvent {
@Serializable
object NavigateBack : NavigationEvent()

@Serializable
object NavigateToHome : NavigationEvent()

@Serializable
object NavigateToSettings : NavigationEvent()
}
}

Я ожидал, что когда я нажму кнопку настроек, составной элемент настроек будет помещен в начало стека составных элементов с помощью navController.navigate


Подробнее здесь: https://stackoverflow.com/questions/793 ... -viewmodel