RecycleView displaying only the first item

You need to change your item_layout height as wrap_content
if your are using Android Support Library v 23.2.0 and above

<?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="wrap_content">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/tv_detail"/>
</RelativeLayout>