AndroidAPS/app/src/main/res/layout/bgsource_fragment.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:paddingTop="2dp"
    tools:context="info.nightscout.androidaps.plugins.source.BGSourceFragment">

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/recyclerview"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

    </androidx.recyclerview.widget.RecyclerView>

</LinearLayout>