@Test
    public void noOperandShowsComputationError() {
        final String expectedResult = getApplicationContext().getString(R.string.computationError);
        onView(withId(R.id.operation_add_btn)).perform(click());
        onView(withId(R.id.operation_result_text_view)).check(matches(withText(expectedResult)));
    }
Use {@link ActivityScenario} to create and launch of the activity.
runner/AndroidTestOrchestratorSample/app/src/androidTest/java/com/example/android/testing/androidtestorchestratorsample/CalculatorInstrumentationTest.java