wiimmfi-watcher/app/src/main/res/layout/room_fragment.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"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:foregroundTint="@color/white"

    >

    <TextView
        android:id="@+id/room_header_text"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:padding="18dp"
        android:text="TextView"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" />

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/player_data_recycler_view"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/room_header_text"
        android:fitsSystemWindows="true">

    </androidx.recyclerview.widget.RecyclerView>

    <com.google.android.material.floatingactionbutton.FloatingActionButton
        android:id="@+id/refresh_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="20dp"
        android:clickable="true"
        android:enabled="true"
        android:foregroundTint="#FFFFFF"
        app:backgroundTint="#1E88E5"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:srcCompat="@drawable/ic_baseline_refresh_24"
        app:tint="@color/white" />

</androidx.constraintlayout.widget.ConstraintLayout>