<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.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=".CameraActivity">

    <Button
        android:id="@+id/button_camera"
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:layout_marginBottom="48dp"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:background="@drawable/focus_marker_outline"
        app:layout_constraintBottom_toBottomOf="@+id/camera"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" />

    <com.otaliastudios.cameraview.CameraView
        android:id="@+id/camera"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:keepScreenOn="true"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

    </com.otaliastudios.cameraview.CameraView>

</android.support.constraint.ConstraintLayout>