Steps to Setup Espresso for Android Apps

Before we start the setup process for Espresso for testing, it is recommended to turn off the following system settings on your virtual or physical device(s).

• On your device, under Settings->Developer options disable the following 3 settings:
  • Window animation scale
  • Transition animation scale
  • Animator duration scale

Download Espresso

Make sure you have installed the latest Android Support Repository under Extras.

Open your app’s build.gradle file. This is usually not the top-level build.gradle file but app/build.gradle.
Add the following lines inside dependencies:

androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2.2'
androidTestCompile 'com.android.support.test:runner:0.5'

Here is the list of few more artifacts available for Espresso.

// Espresso core
androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2.2'
// Espresso-contrib for DatePicker, RecyclerView, Drawer actions, Accessibility checks, CountingIdlingResource
androidTestCompile 'com.android.support.test.espresso:espresso-contrib:2.2.2'
// Espresso-web for WebView support
androidTestCompile 'com.android.support.test.espresso:espresso-web:2.2.2'
// Espresso-idling-resource for synchronization with background jobs
androidTestCompile 'com.android.support.test.espresso:espresso-idling-resource:2.2.2'
// Espresso-intents for validation and stubbing of Intents
androidTestCompile 'com.android.support.test.espresso:espresso-intents:2.2.2'

Set the instrumentation runner

Add to the same build.gradle file the following line in android.defaultConfig:

testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

Example build.gradle file

apply plugin: 'com.android.application'

android {
    compileSdkVersion 25
    buildToolsVersion "26.0.0"

    defaultConfig {
        applicationId "in.developersjournal.app"
        minSdkVersion 15
        targetSdkVersion 25
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
}

dependencies {
    // App's dependencies, including test
    compile 'com.android.support:support-annotations:22.2.0'

    // Testing-only dependencies
    androidTestCompile 'com.android.support.test:runner:0.5'
    androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2.2'
}

Add the first test

Android Studio creates tests by default in src/androidTest/java/com.example.package/

androidTest is the location where Android uses Connected Tests. For more information please check out the following Getting Started with Android Testing.

Example JUnit4 test using Rules:

@RunWith(AndroidJUnit4.class)
@LargeTest
public class HelloWorldEspressoTest {

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

    @Test
    public void listGoesOverTheFold() {
        onView(withText("Hello world!")).check(matches(isDisplayed()));
    }
}

Running tests in Android Studio

Create a test configuration

In Android Studio:

• Open Run menu -> Edit Configurations
• Add a new Android Tests configuration
• Choose a module
• Add a specific instrumentation runner:

android.support.test.runner.AndroidJUnitRunner

Run the newly created configuration.

From command-line via Gradle

Execute

./gradlew connectedAndroidTest