<?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=".MainActivity">


    <Button
        android:id="@+id/btnVibOne"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="72dp"
        android:text="Vib One"
        app:layout_constraintEnd_toStartOf="@+id/btnVibTwo"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/btnVibTwo"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="72dp"
        android:layout_marginEnd="8dp"
        android:layout_marginRight="8dp"
        android:text="Vib Two"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toEndOf="@+id/btnVibOne"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/btnVibThree"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="56dp"
        android:text="Vib Three"
        app:layout_constraintEnd_toStartOf="@+id/btnVibFour"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/btnVibOne" />

    <Button
        android:id="@+id/btnVibFour"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="56dp"
        android:layout_marginEnd="8dp"
        android:layout_marginRight="8dp"
        android:text="Vib Four"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toEndOf="@+id/btnVibThree"
        app:layout_constraintTop_toBottomOf="@+id/btnVibTwo" />

    <Button
        android:id="@+id/btnVibFive"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="56dp"
        android:text="Vib Five"
        app:layout_constraintEnd_toStartOf="@+id/btnVibSix"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/btnVibThree" />

    <Button
        android:id="@+id/btnVibSix"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="56dp"
        android:layout_marginEnd="8dp"
        android:layout_marginRight="8dp"
        android:text="Vib Six"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.5"
        app:layout_constraintStart_toEndOf="@+id/btnVibFive"
        app:layout_constraintTop_toBottomOf="@+id/btnVibFour" />

</android.support.constraint.ConstraintLayout>