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androidnavigationfragment

FragmentContainerView as NavHostFragment


Seems like using the FragmentContainerView doesn't work right out of the box?

<androidx.fragment.app.FragmentContainerView
        class="androidx.navigation.fragment.NavHostFragment"
        android:id="@+id/fragment_nav_host"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:defaultNavHost="true"
        app:navGraph="@navigation/nav_app" />

Here's my code using fragment-ktx:1.2.0-rc01 and I'm just always getting this error:

Caused by: java.lang.IllegalStateException: Activity ...MainActivity@797467d does not have a NavController set on 2131296504

Just using <fragment> works and AFAIK, it's just supposed to be replaced by FragmentContainerView.

Am I missing something or was anyone able to use FragmentContainerView as a NavHostFragment?

Many thanks!


Solution

  • Due to this bug-report: https://issuetracker.google.com/issues/142847973

    This is the only way (currently):

    val navHostFragment = supportFragmentManager
        .findFragmentById(R.id.my_nav_host_fragment) as NavHostFragment
    val navController = navHostFragment.navController
    

    (Java):

    NavHostFragment navHostFragment =
        (NavHostFragment) getSupportFragmentManager()
            .findFragmentById(R.id.my_nav_host_fragment);
    NavController navController = navHostFragment.getNavController();