You must call setGraph() before calling getGraph()

Question

I have bottom navigation and replaced the tag with FragmentContainerView. It gives me an error stating that it does not have a NavController set. I posted this question on StackOverflow and fixed the problem. However, I encountered the following error when the orientation was changed and an item was selected in the bottom navigation.

java.lang.IllegalStateException: You must call setGraph() before calling 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" /

finding fragment

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)

Answer 1

This is fixed as per the 2.2.0-rc03 release notes:

NavHostFragment now correctly restores the graph after a configuration change when used with FragmentContainerView. (b/143752103)

So make sure you are using 2.2.0-rc03.