ScaffoldState与Material3的未解析参考误差

Question

Android使用Unresolved Reference为ScaffoldState抛出一个Material3错误。我怎么才能让它起作用？

import androidx.compose.foundation.clickable
import androidx.compose.material3.*
import androidx.compose.material3.Icon
import androidx.compose.material3.IconButton
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.rememberCoroutineScope
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.navigation.NavController
import kotlinx.coroutines.launch

@Composable
fun CustomAppBar(
    title: String,
    backGroundColor: Color = Color.White,
    actions: @Composable () -> Unit = { },
    scaffoldState: ScaffoldState? = null, // Errors here...
    navController: NavController,
) {
    val scope = rememberCoroutineScope()

    SmallTopAppBar(
        title = {
            Text(
                title,
                maxLines = 1,
                overflow = TextOverflow.Ellipsis
            )
        },
        colors = TopAppBarDefaults.smallTopAppBarColors(
            containerColor = containerBackGroundColor,
            titleContentColor = titleContentColor
        ),
        navigationIcon = if (navController?.previousBackStackEntry != null) {
            {
                IconButton(onClick = { navController.navigateUp() }) {
                    Icon(
                        imageVector = Icons.Filled.ArrowBack,
                        contentDescription = "Back"
                    )
                }
            }
        } else {
            {
                IconButton(onClick = {
                    scope.launch {
                        scaffoldState?.drawerState?.open()
                    }
                }) {
                    Icon(
                        Icons.Filled.Menu,
                        contentDescription = "Nav drawer icon",
                    )
                }
            }
        },
        actions = {
            actions()
        }
    )
}

属地

implementation "androidx.core:core-ktx:1.8.0"
implementation "androidx.compose.ui:ui:1.2.1"
implementation "androidx.compose.material3:material3:1.0.0-beta01"
implementation "androidx.compose.ui:ui-tooling-preview:1.2.1"
implementation "androidx.lifecycle:lifecycle-runtime-ktx:2.3.1"
implementation "androidx.activity:activity-compose:1.3.1"
implementation "androidx.compose.compiler:compiler:1.3.0"
implementation "androidx.navigation:navigation-runtime:2.5.1"
implementation "com.google.accompanist:accompanist-navigation-animation:0.23.1"

Answer 1

我看了一下我的依赖项，ScaffoldState是com.google.android.material:material:$materialVersion"的一部分。

在我的例子中，我有1.7.0-alpha03所以com.google.android.material:material:1.7.0-alpha03 (可能会有更新的版本)。

我确信，如果您添加了这一项，然后正确的导入：

import androidx.compose.material.ScaffoldState你应该能够使用它。

别忘了同步格莱德尔。

Answer 2

是窗户。去File > Invalidate Caches > (Check Everything) Invalidate Caches and Restart。不妨在连接到internet的同时尝试一个Build > Rebuild Project，以确保所有依赖项都被正确下载。希望您不需要从内部文件夹手工分解部分下载的库.就像把头掉进脏衣服里一样。还有点让我想起复仇者队的场景，在那里他们修复了一个被部分炸毁的涡轮推进器。