ExemploTesteInterface_executarTesteLoginContaCorreta.java

@Test
public void executarTesteLoginContaCorreta() {

    //Insere o usuário no campo user
    onView(withId(R.id.user)).perform(typeText("Testeapp"), closeSoftKeyboard());

    //Insere a senha no campo pass
    onView(withId(R.id.pass)).perform(typeText("Password"), closeSoftKeyboard());

    //Clica no botao submit
    onView(withId(R.id.submit)).perform(click());

    //Verifica se o texto é exibido no textView da SecondActivity
    onView(withId(R.id.success)).check(matches(withText("Logado!")));

}