<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/apk/res-auto">

    <item
            android:id="@+id/action_filter_search"
            android:title=" "
            app:actionViewClass="android.support.v7.widget.SearchView"
            app:showAsAction="collapseActionView|always" />

</menu>