samples/RhythmGame/src/main/res/layout/activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.google.oboe.samples.rhythmgame.MainActivity">

    <com.google.oboe.samples.rhythmgame.GameSurfaceView
        android:id="@+id/glSurfaceView"
        android:layout_width="match_parent"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:layout_marginBottom="0dp"
        android:layout_marginEnd="0dp"
        android:layout_marginStart="0dp"
        android:layout_marginTop="0dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:layout_height="match_parent" />

    <TextView
        android:id="@+id/instructionsBlock"
        android:layout_width="294dp"
        android:layout_height="159dp"
        android:layout_marginStart="16dp"
        android:layout_marginTop="16dp"
        android:clickable="false"
        android:ems="10"
        android:focusable="false"
        android:gravity="start|top"
        android:inputType="textMultiLine"
        android:text="See https://github.com/google/oboe/blob/main/samples/RhythmGame/README.md for instructions. There is a link to a codelab to follow along with."
        android:textColor="#FFFFFF"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>