Example of how to add a header to a RecyclerView in XML

recycler_view_with_header.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout 
    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">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <!-- Replace this ImageView with your header view -->
        <ImageView
            android:id="@+id/header"
            android:layout_width="match_parent"
            android:layout_height="300dp"
            app:layout_scrollFlags="scroll" />

    </android.support.design.widget.AppBarLayout>

    <!-- This can be any scrolling view -->
    <android.support.v7.widget.RecyclerView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:layout_behavior="@string/appbar_scrolling_view_behavior" />

</android.support.design.widget.CoordinatorLayout>