小编Meh*_*ncb的帖子

我有个问题。

问题是，当我导航到“添加问题”屏幕时，我不知道如何隐藏底部应用程序栏。

我需要你的帮助。

这是带有底部应用栏的“我的屏幕”

@Composable
fun Navigation() {
    val navController = rememberNavController()
    val items = listOf(Screen.Home, Screen.Search, Screen.Notifications, Screen.Profil)

    Scaffold(
        bottomBar = {
            bottomAppNavigation(navController = navController, items)

        }
    ) {
        Box(modifier = Modifier.padding(it)) {
            ScreenController(navController = navController)
        }

    }
}

这是我的带有 navHost 的控制器

@ExperimentalComposeUiApi
@Composable
fun ScreenController(navController: NavHostController) {
    NavHost(navController = navController, startDestination = Screen.Home.route) {
        composable(Screen.Home.route) {
            HomeScreen(navController)
        }
        composable(Screen.Search.route) {
            SearchScreen(navController, it)
        }
        composable(Screen.Notifications.route) {

        }
        composable(Screen.Profil.route) {
            user_profil()
        }
        composable("Ask_question") {
            AskScreen(navController)
        }
    }
}

我认为问题是因为这就像活动和片段，我有一个可组合屏幕所在的盒子，我的所有页面都在他里面。

我已将 Jetpack Compose 从 1.1.0-beta03 升级到 1.1.0-beta04，除了需要进行一些更改之外，没有发生任何事情，但现在当我在“DetailScreen”上启动应用程序时遇到此错误。

E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.antigaspi, PID: 6067
java.lang.IllegalStateException: Place was called on a node which was placed already
    at androidx.compose.ui.node.LayoutNode.onNodePlaced$ui_release(LayoutNode.kt:941)
    at androidx.compose.ui.node.InnerPlaceable.placeAt-f8xVGno(InnerPlaceable.kt:125)
    at androidx.compose.ui.layout.Placeable.access$placeAt-f8xVGno(Placeable.kt:31)
    at androidx.compose.ui.layout.Placeable$PlacementScope.placeRelative(Placeable.kt:359)
    at androidx.compose.ui.layout.Placeable$PlacementScope.placeRelative$default(Placeable.kt:179)
    at androidx.compose.foundation.layout.PaddingModifier$measure$1.invoke(Padding.kt:370)
    at androidx.compose.foundation.layout.PaddingModifier$measure$1.invoke(Padding.kt:368)
    at androidx.compose.ui.layout.MeasureScope$layout$1.placeChildren(MeasureScope.kt:68)
    at androidx.compose.ui.node.DelegatingLayoutNodeWrapper.placeAt-f8xVGno(DelegatingLayoutNodeWrapper.kt:126)
    at androidx.compose.ui.layout.Placeable.access$placeAt-f8xVGno(Placeable.kt:31)
    at androidx.compose.ui.layout.Placeable$PlacementScope.place-70tqf50(Placeable.kt:370)
    at androidx.compose.ui.node.OuterMeasurablePlaceable.placeOuterWrapper-f8xVGno(OuterMeasurablePlaceable.kt:171)
    at androidx.compose.ui.node.OuterMeasurablePlaceable.access$placeOuterWrapper-f8xVGno(OuterMeasurablePlaceable.kt:28)

我需要你的帮助。

一切都在标题中，我不知道我该怎么做......请帮助我。我使用了很多东西，如补间、枚举类等，但没有用，我想要 200dp 的初始值，当活动打开时，2 秒后，图像在 2 秒内从 200dp 变为 100dp。谢谢。