[我有底部导航,也用<fragment>
替换了FragmentContainerView
标记,它给我有关没有设置NavController的错误,然后我被发布了this问题并解决了问题,但是我知道了更改方向并在底部导航中选择项目时出现以下错误
java.lang.IllegalStateException:您必须先调用setGraph(),然后再调用getGraph()
FragmentContainer
<androidx.fragment.app.FragmentContainerView
android:id="@+id/nav_host_fragment"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:navGraph="@navigation/mobile_navigation" /
查找片段
val navHostFragment = supportFragmentManager.findFragmentById(R.id.nav_host_fragment) as NavHostFragment
val navController = navHostFragment.navController
// Passing each menu ID as a set of Ids because each
// menu should be considered as top level destinations.
val appBarConfiguration = AppBarConfiguration(
setOf(
R.id.navigation_classes, R.id.navigation_schedule, R.id.navigation_settings
)
)
setupActionBarWithNavController(navController, appBarConfiguration)
navView.setupWithNavController(navController)
NavHostFragment
现在与FragmentContainerView
一起使用时,在更改配置后可以正确地还原图形。 (b/143752103)
因此请确保您正在使用2.2.0-rc03
。