标签: navigation-compose

我有一个名为 的可组合项ParentScreen和一个ViewModel名为ParentViewModel. 在 中ParentViewModel，我正在从我的存储库中收集一个值。

class MyRepo @Inject constructor() {
    fun getParentData() = System.currentTimeMillis().toString() // some dummy value
}

@HiltViewModel
class ParentViewModel @Inject constructor(
    myRepo: MyRepo
) : ViewModel() {
    private val _parentData = MutableStateFlow("")
    val parentData = _parentData.asStateFlow()

    init {
        val realData = myRepo.getParentData()
        _parentData.value = realData
    }
}

@Composable
fun ParentScreen(
    parentViewModel: ParentViewModel = hiltViewModel()
) {
    val parentData by parentViewModel.parentData.collectAsState()
    ChildWidget(parentData = parentData)
}

在可组合项内部ParentScreen，我有一个ChildWidget可组合项，它有自己的ViewModel …

我在我的应用程序中使用 Navigation-Compose ：

override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            ComposeTheme {
                val navController = rememberNavController()
                NavHost(navController = navController, startDestination = Screens.Dashboard.title) {
                    composable(Screens.Dashboard.title) {
                        DashboardScreen(navController)
                    }
                    composable(
                        Screens.Section.title, arguments = listOf(
                            navArgument(LINK) {
                                type = AssetParamType()
                            }
                        )
                    ) {
                        SectionDetailsScreen(navController)
                    }
                }
            }
        }
    }

我在每个屏幕上都有一个单独的应用程序栏，例如：

@Composable
fun DashboardScreen(
    navController: NavHostController,
    viewModel: DashboardViewModel = hiltViewModel()
) {
    Scaffold(
        topBar = {
            TopAppBar(
                title = {
                    Box(
                        contentAlignment = Alignment.Center,
                        modifier = Modifier.fillMaxSize()
                    ) {
                        Text(text = stringResource(id …

我试图将音频文件位置（/storage/emulated/0/Android/media/...）作为字符串从第一个屏幕传递home_screen到第二个屏幕detail_screen，当我正常传递上面的字符串作为参数时，我收到此错误

java.lang.IllegalArgumentException: Navigation destination that matches request NavDeepLinkRequest{ uri=android-app://androidx.navigation/detail_screen/45193/'/storage/emulated/0/Android/media/com.Slack/Notifications/Slack - Here you go.mp3' } cannot be found in the navigation graph NavGraph(0x0) startDestination={Destination(0x442b361f) route=home_screen}

至于这个地方，如果我传递像这样的字符串Here you go.mp3，它工作得很好！

我认为 Compose Navigation 无法区分/

我正在使用 Jetpack Compose 和 Android 导航组件。当我在带有 的屏幕上时AlertDialog，我无法返回。我猜这是由于AlertDialog捕获了后退按钮事件。但是我不知道如何连接AlertDialog到导航组件？有没有官方的方法或最佳实践来做到这一点？这是我的代码：

// sample with a screen and a "navigate to dialog" button.
// once the button is pressed, an AlertDialog is shown.
// Using the back button while the AlertDialog is open has no effect ):    

@Composable
fun MyNavHost(navController: NavHostController, modifier: Modifier = Modifier) {
    NavHost(
        navController = navController,
        startDestination = "start_route",
        modifier = modifier
    ) {
        composable("start_route") {
            Text("start screen")
        }
        
        // this is my screen with …