android - ClassNotFoundException when using androidx.fragment.app.FragmentContainerView

Question

I'm trying to transition from using a FrameLayout to using FragmentContainerView and from the tutorials I've seen, it should be pretty easy. However, when I run my app after making the change, I get

Error inflating class androidx.fragment.app.FragmentContainerView
Caused by: java.lang.ClassNotFoundException: androidx.fragment.app.FragmentContainerView

my layout file is pretty simple:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="match_parent"
android:layout_width="match_parent"
xmlns:tools="http://schemas.android.com/tools"
tools:showIn="@layout/app_bar_main">

    <androidx.fragment.app.FragmentContainerView
        android:id="@+id/fragment_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
</LinearLayout>

Do I need to add something into my build.gradle or something? Why can't it find the class?

Answer 1

That's in androidx.fragment 1.2.0 or higher:

implementation "androidx.fragment:fragment:1.2.0"