Espresso: How to use R.string resources of androidTest folder

I want to put data in xml file of androidTest/res/values/string.xml folder. I have created the file say test.xml with below contents.

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="test">hello</string>
</resources>

When i am trying to access the field test via R.string.test. It is not accessible and says "cannot resolve symbol test". Can someone please advice me here.