Hi I try to use Map Box with Android studio for learning how to build an GIS App.I follow this tutorial, <https://www.mapbox.com/install/android/>
But When I try to test the installation or some examples I receive the following error.

> 
> Android resource compilation failed Output: 
>  C:\Users\Vassilis\AndroidStudioProjects\mapBox\_test\_nbg\app\src\main\res\layout\activity\_main.xml:3:
>  error: duplicate attribute.
> 
> 
> Command:
>  C:\Users\Vassilis.gradle\caches\transforms-1\files-1.1\aapt2-3.2.1-4818971-windows.jar\efd9526a9f78532313c282340621c36b\aapt2-3.2.1-4818971-windows\aapt2.exe
>  compile --legacy \
>  -o \
>  C:\Users\Vassilis\AndroidStudioProjects\mapBox\_test\_nbg\app\build\intermediates\res\merged\debug
>  \
>  C:\Users\Vassilis\AndroidStudioProjects\mapBox\_test\_nbg\app\src\main\res\layout\activity\_main.xml
>  Daemon: AAPT2 aapt2-3.2.1-4818971-windows Daemon #2
> 
> 
> 

The code of activity\_main.xml is:

```
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:mapbox="http://schemas.android.com/apk/res-auto"
    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">

    <com.mapbox.mapboxsdk.maps.MapView
        android:id="@+id/mapView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        mapbox:mapbox_cameraTargetLat="40.73581"
        mapbox:mapbox_cameraTargetLng="-73.99155"
        mapbox:mapbox_cameraZoom="11"
        mapbox:mapbox_styleUrl="mapbox://styles/mapbox/streets-v11"
        tools:layout_editor_absoluteX="0dp"
        tools:layout_editor_absoluteY="0dp" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

```

Maybe that image helping more
[![enter image description here](https://i.stack.imgur.com/HSEbo.png)](https://i.stack.imgur.com/HSEbo.png)