Java – How do I see by ID in my Espresso test?

I don’t understand how to get View from screen in my Espresso test using findViewById.

I

will use espresso autotest to go to a screen in my application, and then I want to check if the screen is correct. To do this, I need to get the toolbar from the screen and check some of his properties.
First, I tried to do this using the ViewInteractions object, but I could convert it to a View, but I couldn’t access the object properties.

I

want to get View directly using findViewById, but I know how to use it properly.

public void goToMyOrders (){
        BottomTabBar bottomTabBar = new BottomTabBar();
        bottomTabBar.profileButton.perform(click());
        myOrderButton.perform(click());
        ViewInteraction toolbarView = onView(allOf(withId(R.id.custom_font_toolbar)));
        toolbarView.getContext();
        toolbarView.check(matches(withText("Мои заказы")));
    }

No, I think you’re a bit wrong about the idea of testing. First of all, the Toolbar does not extend/inherit the TextView, so it cannot have text, but you can place a TextView inside the Toolbar

Create a new sample application and put this layout into your activity_main.xml

:

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=". MainActivity">

<Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        app:layout_constraintHeight_percent="0.3"
        app:layout_constraintTop_toTopOf="parent"
        android:background="@color/colorAccent"/>

<TextView
        android:id="@+id/textview"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:layout_constraintTop_toTopOf="@id/toolbar"
        app:layout_constraintBottom_toBottomOf="@id/toolbar"
        app:layout_constraintLeft_toLeftOf="@id/toolbar"
        app:layout_constraintRight_toRightOf="@id/toolbar"
        android:text="SomeTextBeforeChange"
        android:textColor="#FFFFFF"/>

<Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:layout_constraintTop_toBottomOf="@id/toolbar"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        android:text="Change text after click"/>

In your MainActivity:

public class MainActivity extends AppCompatActivity {

@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

Button button = findViewById(R.id.button);
    final TextView textView = findViewById(R.id.textview);
    button.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            textView.setText("Changed text");
        }
    });
}

As you can see, this might be a similar View to yours – Toolbar, TextView, and Button that change the text of the TextView.

Let’s now use Espresso for automated testing

1. Create a new class in your androidTest subfolder and name it e.g. MainActivityTest

2. Define an ActivityTestRule read the information in Android docs
   You may also need those Gradle dependencies:

   androidTestImplementation 'com.android.support.test:runner:1.0.2'<br/>
androidTestImplementation 'com.android.support.test:rules:1.0.2'<br/>
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'

   Rules:
   @Rule
public ActivityTestRule<MainActivity> rule = new ActivityTestRule<>
(MainActivity.class);

   Then define a public method with a return type of void, annotated as @Test .
   In this method you can define your TextView call Espresso.onView(ViewMatchers.withId(your.textview.id));

To check if it contains the specified text, you need to call ‘textview.check(ViewAssertions.matches(ViewMatchers.withText(“expected text”))));

I

won’t explain exactly what these methods do, as their names speak for themselves, but if you’re having some trouble understanding them, you can find plenty of resources on StackOverflow. For my code above, I wrote the following simple test, so you can analyze it if you want:

public class MainActivityTest {

@Rule
public ActivityTestRule<MainActivity> rule = new ActivityTestRule<>(MainActivity.class);

@Test
public void checkIfButtonChangesText(){
     TextView
    ViewInteraction textView = Espresso.onView(ViewMatchers.withId(R.id.textview));
     Button
    ViewInteraction button = Espresso.onView(ViewMatchers.withId(R.id.button));

check if TextView contains text: "SomeTextBeforeChange"
    textView.check(ViewAssertions.matches(ViewMatchers.withText("SomeTextBeforeChange")));

 analogically with Button, text: "Change text after click"
    button.check(ViewAssertions.matches(ViewMatchers.withText("Change text after click")));

 perform button click:
    button.perform(ViewActions.click());

Check if text has been changed to "Changed text"
    textView.check(ViewAssertions.matches(ViewMatchers.withText("Changed text")));

}

}