Quelle  activity_backup_admin.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/coordinator"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="ch.threema.app.activities.BackupAdminActivity">

    <com.google.android.material.appbar.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <FrameLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <include layout="@layout/toolbar_view_noshadow" />

            <include layout="@layout/connection_indicator" />

        </FrameLayout>

        <include layout="@layout/notice_with_close_button" />

        <com.google.android.material.tabs.TabLayout
            android:id="@+id/tabs"
            android:background="@android:color/transparent"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />

    </com.google.android.material.appbar.AppBarLayout>

    <androidx.viewpager.widget.ViewPager
        android:id="@+id/pager"
        android:background="?android:attr/colorBackground"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior" />

</androidx.coordinatorlayout.widget.CoordinatorLayout>