app/src/main/res/layout/activity_friends_tracker.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">
<com.google.android.gms.maps.MapView
android:id="@+id/friends_map"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<com.google.android.material.button.MaterialButton
android:id="@+id/find_user_button"
android:layout_width="40dp"
android:layout_height="40dp"
android:layout_marginBottom="16dp"
android:layout_marginEnd="16dp"
android:background="@drawable/circle_button_shape"
android:checkable="true"
app:backgroundTint="@color/navigation_bar_background"
app:icon="@drawable/gps_button_selector"
app:iconGravity="textStart"
app:iconPadding="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="@id/friends_map"/>
</androidx.constraintlayout.widget.ConstraintLayout>