app/src/main/res/xml/pref_headers.xml

<preference-headers xmlns:android="http://schemas.android.com/apk/res/android">

    <!-- These settings headers are only used on tablets. -->

    <header
        android:fragment="com.example.johnnysun.myapplication.SettingsActivity$GeneralPreferenceFragment"
        android:title="@string/pref_header_general" android:icon="@drawable/ic_info_black_24dp" />

    <header
        android:fragment="com.example.johnnysun.myapplication.SettingsActivity$NotificationPreferenceFragment"
        android:title="@string/pref_header_notifications"
        android:icon="@drawable/ic_notifications_black_24dp" />

</preference-headers>