Getting this exception when I quickly switch between destinations (i.e. Bottom navigation: HomeScreen -> SettingsScreen -> HomeScreen). Navigation is implemented according to the example in the documentation and sampleApp. Perhaps this is a Jetpack Compose bug, since I did not find a similar error on the Internet.
Screens:
sealed class Screen(
val route: String,
@StringRes val title: Int,
@DrawableRes val icon: Int) {
object Home : Screen("HomeScreen", R.string.app_name, R.drawable.ic_baseline_chevron_right_24)
object Scanner : Screen("ScannerScreen", R.string.app_name, R.drawable.ic_baseline_chevron_right_24)
object Settings : Screen("SettingsScreen", R.string.app_name, R.drawable.ic_baseline_chevron_right_24)
}
Bottom navigation:
@Composable
fun BottomNavigationBar(navController: NavController) {
val items = listOf(
Screen.Home,
Screen.Scanner,
Screen.Settings
)
BottomNavigation {
val navBackStackEntry = navController.currentBackStackEntryAsState()
val currentRoute = navBackStackEntry.value?.destination?.route
items.forEach { item ->
BottomNavigationItem(
icon = { Icon(painter = painterResource(id = item.icon), contentDescription = item.title.toString()) },
label = { Text(item.title.toString()) },
selected = currentRoute == item.route,
onClick = {
navController.navigate(item.route) {
navController.graph.startDestinationRoute?.let {
popUpTo(it) {
saveState = true
}
}
launchSingleTop = true
restoreState = true
}
}
)
}
}
}
Navigation:
@ExperimentalMaterialApi
@ExperimentalPermissionsApi
@Composable
fun MainScreen() {
val navController = rememberNavController()
Scaffold(
bottomBar = { BottomNavigationBar(navController) }
) {
Box(modifier = Modifier.padding(it)) {
NavigationHost(navController)
}
}
}
@ExperimentalPermissionsApi
@ExperimentalMaterialApi
@Composable
fun NavigationHost(navController: NavHostController) {
NavHost(
navController = navController,
startDestination = Screen.Scanner.route) {
composable(Screen.Home.route) {
HomeScreen()
}
composable(Screen.Scanner.route) {
ScannerScreen()
}
composable(Screen.Settings.route) {
SettingsScreen()
}
}
}
@Composable
fun HomeScreen() {
// Body
}
@Composable
fun ScannerScreen() {
// Body
}
@Composable
fun SettingsScreen() {
// Body
}
Logs:
java.lang.IllegalStateException: You cannot access the NavBackStackEntry's ViewModels until it is added to the NavController's back stack (i.e., the Lifecycle of the NavBackStackEntry reaches the CREATED state).
at androidx.navigation.NavBackStackEntry.getViewModelStore(NavBackStackEntry.kt:174)
at androidx.lifecycle.ViewModelProvider.<init>(ViewModelProvider.java:99)
at androidx.lifecycle.viewmodel.compose.ViewModelKt.get(ViewModel.kt:82)
at androidx.lifecycle.viewmodel.compose.ViewModelKt.viewModel(ViewModel.kt:72)
at androidx.navigation.compose.NavBackStackEntryProviderKt.SaveableStateProvider(NavBackStackEntryProvider.kt:86)
at androidx.navigation.compose.NavBackStackEntryProviderKt.access$SaveableStateProvider(NavBackStackEntryProvider.kt:1)
at androidx.navigation.compose.NavBackStackEntryProviderKt$LocalOwnersProvider$1.invoke(NavBackStackEntryProvider.kt:51)
at androidx.navigation.compose.NavBackStackEntryProviderKt$LocalOwnersProvider$1.invoke(NavBackStackEntryProvider.kt:50)
at androidx.compose.runtime.internal.ComposableLambdaImpl.invoke(ComposableLambda.jvm.kt:107)
at androidx.compose.runtime.internal.ComposableLambdaImpl.invoke(ComposableLambda.jvm.kt:34)
at androidx.compose.runtime.CompositionLocalKt.CompositionLocalProvider(CompositionLocal.kt:215)
at androidx.navigation.compose.NavBackStackEntryProviderKt.LocalOwnersProvider(NavBackStackEntryProvider.kt:46)
at androidx.navigation.compose.NavHostKt$NavHost$3.invoke(NavHost.kt:132)
at androidx.navigation.compose.NavHostKt$NavHost$3.invoke(NavHost.kt:131)
at androidx.compose.runtime.internal.ComposableLambdaImpl.invoke(ComposableLambda.jvm.kt:116)
at androidx.compose.runtime.internal.ComposableLambdaImpl.invoke(ComposableLambda.jvm.kt:34)
at androidx.compose.animation.CrossfadeKt$Crossfade$1$1.invoke(Crossfade.kt:74)
at androidx.compose.animation.CrossfadeKt$Crossfade$1$1.invoke(Crossfade.kt:69)
at androidx.compose.runtime.internal.ComposableLambdaImpl.invoke(ComposableLambda.jvm.kt:107)
at androidx.compose.runtime.internal.ComposableLambdaImpl.invoke(ComposableLambda.jvm.kt:34)
at androidx.compose.animation.CrossfadeKt.Crossfade(Crossfade.kt:86)
at androidx.navigation.compose.NavHostKt.NavHost(NavHost.kt:131)
at androidx.navigation.compose.NavHostKt$NavHost$4.invoke(Unknown Source:13)
at androidx.navigation.compose.NavHostKt$NavHost$4.invoke(Unknown Source:10)
at androidx.compose.runtime.RecomposeScopeImpl.compose(RecomposeScopeImpl.kt:140)
at androidx.compose.runtime.ComposerImpl.recomposeToGroupEnd(Composer.kt:2156)
at androidx.compose.runtime.ComposerImpl.skipCurrentGroup(Composer.kt:2399)
at androidx.compose.runtime.ComposerImpl$doCompose$2$5.invoke(Composer.kt:2580)
at androidx.compose.runtime.ComposerImpl$doCompose$2$5.invoke(Composer.kt:2573)
at androidx.compose.runtime.SnapshotStateKt.observeDerivedStateRecalculations(SnapshotState.kt:540)
at androidx.compose.runtime.ComposerImpl.doCompose(Composer.kt:2566)
at androidx.compose.runtime.ComposerImpl.recompose$runtime_release(Composer.kt:2542)
at androidx.compose.runtime.CompositionImpl.recompose(Composition.kt:613)
at androidx.compose.runtime.Recomposer.performRecompose(Recomposer.kt:764)
at androidx.compose.runtime.Recomposer.access$performRecompose(Recomposer.kt:103)
at androidx.compose.runtime.Recomposer$runRecomposeAndApplyChanges$2$2.invoke(Recomposer.kt:447)
at androidx.compose.runtime.Recomposer$runRecomposeAndApplyChanges$2$2.invoke(Recomposer.kt:416)
at androidx.compose.ui.platform.AndroidUiFrameClock$withFrameNanos$2$callback$1.doFrame(AndroidUiFrameClock.android.kt:34)
at androidx.compose.ui.platform.AndroidUiDispatcher.performFrameDispatch(AndroidUiDispatcher.android.kt:109)
at androidx.compose.ui.platform.AndroidUiDispatcher.access$performFrameDispatch(AndroidUiDispatcher.android.kt:41)
at androidx.compose.ui.platform.AndroidUiDispatcher$dispatchCallback$1.doFrame(AndroidUiDispatcher.android.kt:69)
2021-08-12 11:00:49.484 8306-8306/com.example.smartlumnew E/AndroidRuntime: at android.view.Choreographer$CallbackRecord.run(Choreographer.java:1008)
at android.view.Choreographer.doCallbacks(Choreographer.java:809)
at android.view.Choreographer.doFrame(Choreographer.java:740)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:995)
at android.os.Handler.handleCallback(Handler.java:938)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:246)
at android.app.ActivityThread.main(ActivityThread.java:8512)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:602)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1130)
