headerTest.java

List<String> categoryList = getCategoriesArray();
for (int i = 0; i < categoryList.size(); i++) {
    // We don't need to click on the first item as it's already in focus
    if (i > 0) {
        onView(withId(R.id.browse_headers))
                .perform(RecyclerViewActions.actionOnItemAtPosition(i, click()));
    }
    onView(withItemText(categoryList.get(i), R.id.browse_headers))
            .check(matches(isDisplayed()));
}