the-social-notebook-android/app/src/main/res/layout/nav_header_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="@dimen/nav_header_height"
    android:background="@drawable/header_nav"
    android:gravity="bottom"
    android:orientation="vertical"
    android:paddingBottom="60dp"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:theme="@style/ThemeOverlay.AppCompat.Dark">

  <ImageView
    android:layout_width="70dp"
    android:layout_height="70dp"
    android:id="@+id/user_avatar"
    android:src="@drawable/default_avatar"
    android:scaleType="fitCenter"
    android:layout_alignParentTop="true"
    android:layout_alignParentStart="true"
    android:contentDescription="@string/avatar" />
</RelativeLayout>