#⃣ 🤯 🛋️ How to write Android UI tests 👩🏾‍🎨 🐓 👨🏿‍🎤

Hello. We at the Avokado Project continue to talk about autotesting in Android. This article is an overview and comparison of existing tools for writing UI tests.

Let's start by recalling what the testing process usually looks like. Let's call the entity that interacts with the application a client. To interact with the application, the client usually has several interfaces available: API, REST API, CLI, GUI, etc. And if, for example, APIs are used by client programs, then the GUI is used by humans.

Expectations of application behavior are described in the specification. The goal of testing is to verify that the behavior of the application is within specification.

To solve this problem, a set of use cases or test cases is recorded. They are sequences of steps that bring the product to the desired state. Thus, the process of testing an application is the process of passing all test cases.

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Android- :

Espresso.
UiAutomator.
Robotium.
Selendroid.

Android Instrumentation Framework — API Android . — Espresso UiAutomator. Google. . .

UiAutomator

UiAutomator Android SDK 16 API. GUI- : , , , , . , — Ui Automator Viewer.

UiAutomator (black-box). . , , . , , :

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UiAutomator AccessibilityService, . AccessibilityService , . , AccessibilityNodeInfo. View: , .

View AccessibilityEventSource Binder IPC AccessibilityManagerService , , , . AccessibilityManagerService AccessibilityService , , UiAutomator, . AccessibilityService’ UiAutomator’a . View, .

UiAutomator “UI Automator deep diving”.

UiAutomator:

, Binder IPC, . , UiAutomator , . , . , .
, View OpenGL Unity, UiAutomator’a, . , , UiAutomator’a .

, UiAutomator , . Espresso.

Espresso

UI- Google, (white-box). Espresso Android API 10 , . .

Espresso . , .

Espresso — (ViewMatcher), (ViewAction) (ViewAssertion).

Espresso Hamcrest. — , , Espresso — . , , . , .

@Test
public void espressoTest() {
    onView(allOf(allOf(withId(R.id.label_bf_hotelname), 
        isDescendantOfA(withId(R.id.custom_view_trip_review))), 
        isDescendantOfA(withId(R.id.contentView))))
        .check(matches(
            withEffectiveVisibility(Visibility.VISIBLE)
        ));
}

Espresso — Espresso , . . , (idle).

, , , , check ViewInteraction. ViewAssertion idle’.

public ViewInteraction check(ViewAssertion viewAssertion) {
    // (...)
    runSynchronouslyOnUiThread(new Callable<Void>() {
        @Override
        public Void call() {
            uiController.loopMainThreadUntilIdle();
            // (...)
            viewAssertion.check(...)
        }
    });
}

Espresso:

.
. , , . Espresso . UiAutomator.
API Espresso , . .
Espresso .

, , Espresso — , .

Robotium Selendroid

Robotium Selendroid Espresso UiAutomator. C , . , .

Robotium Android API 8+, ( WebView , , API 15), Java. Robotium Recorder IntelliJ IDEA Android Studio.

Selendroid API — 10 19. WebDriver, Inspector record-and-playback-.

, Robotium Selendroid.

Robolectric

, Robolectric , . , Android UI-. Robolectric unit- JUnit Android API.

Android SDK, shadow-. Robolectric , inflate view, , , - Android-. Robolectric , Android, , JVM. , .

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adb. adb: / , , .

API. — , . , , , — , . , , . , .

Appium

Appium — - open source Android iOS. Appium Selenium WebDriver, web-. . Appium- , . Appium API.

. , Appium . HTTP- Node.JS, WebDriver-, . , , . , , Appium .

. Appium , . Android UiAutomator, Espresso. , , . . Espresso UiAutomator.

API. Appium API, WebDriver. Appium , .

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adb. - Appium’ , adb-. , , .

. Appium . — Espresso . - , .

, Appium — Android- . , Kotlin, Java. - Appium . , . : « . , , », « ».

Kakao

Kakao — Kotlin DSL Espresso. Espresso .

API. Kakao — boilerplate- :

KView — Kakao- , . , Kakao , KEditText, KButton .. .
Screen — - PageObject. Screen — , stateless- KView . Screen , , , . Screen’ , .

, , Espresso. :

@Test
public void espressoTest() {
    onView(allOf(allOf(withId(R.id.label_bf_hotelname),
        isDescendantOfA(withId(R.id.custom_view_trip_review))),
        isDescendantOfA(withId(R.id.contentView))))
        .check(matches(
            withEffectiveVisibility(Visibility.VISIBLE)
        ));
}

object MainScreen : Screen<MainScreen>() {
    val hotelName = KTextView { withId(R.id.label_bf_hotelname) }
}

@Test
fun kakaoTest() {
    MainScreen { 
        hotelName { 
            isVisible() 
        } 
    }
}

. Kakao — , Appium, . - . Espresso , , — , ..

. Kakao Espresso, .

. Kakao . API , Espresso-. , , . - - .

. , Espresso. .

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adb. , Espresso.

. , Kakao — DSL Espresso. UiAutomator, API . , , .

Barista

Barista — , Espresso.

API. Kakao, Espresso. Barista — , Espresso-. :

helper- , Espresso . , onView(withId(R.id.button)).perform(click()) Espresso clickOn(R.id.button). clickListItem(R.id.list, 4).
Android- Assertions API.
, .
runtime permission’.
test rule’, , flaky- shared preferences, , .

Barista NestedScrollView, Espresso, . DSL , .

. FlakyTestRule . . , .

. - Espresso.

. , Espresso . Espresso.

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adb. , Espresso.

. Barista . , , . .

Kaspresso

- UI-, , .

API. Kakao. Kaspresso Kakao DSL — Kotlin DSL , Kakao Screen’ KView.

@RunWith(AndroidJUnit4::class)
class OpenHomeScreenTest : TestCase() {

    @Test
    fun kaspressoTest() {
        before { ... }
        .after { ... }
        .run {
            step("1. Open Home screen") { 
                MainScreen {
                    openHomeScreenBtn.click()
                }
            }
            step("2. Check Home title") { 
                HomeScreen {
                    title.isVisible()
                }
            }
            step("3. Do some stuff") { ... }
        }
    }
}

Kaspresso API , . , (. How to write autotests).

. Kaspresso - API Espresso UiAutomator. , , , . , , . Kaspresso Kautomator — Kakao-like UiAutomator, Espresso UiAutomator .

object KakaoScreen : Screen<KakaoScreen>() {
    val title = KTextView { withText(titleText) }
    val btn = KButton { withId(R.id.button1) }
}

object KautomatorScreen : UiScreen<KautomatorScreen>() {
    val title = UiTextView { withText(titleText) }
    val btn = UiButton { withId(pkgName, R.id.button2) }
}

@Test
fun kaspressoTest() {
    KakaoScreen { 
        title.isVisible()
        btn.click()
    }
    KautomatorScreen {
        title.isVisible()
        btn.click()
    }
}

device. , :

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: back, home, recents.

Kaspresso , .

. Kaspresso , . , , ViewAction ViewAssertion, , . , , , (. Configurator).

. Kaspresso Espresso UiAutomator , , ScrollView, , . helper-. , flakySafely:

MainScreen {
    flakySafely {
        btn.click()
    }
}

. , , .

. . , Kaspresso , . :

device.screenshots.take("MainScreen_step_1")

. Localization autotests.

adb. Kaspresso AdbServer — HTTP-, adb-. , , . , adb- . AdbServer , device. API adb-:

adbServer.performAdb("emu sms send +79111111111 $smsText")
adbServer.perfromShell("rm -f $filePath")

AdbServer , , adb.

	Appium	Kakao	Barista	Kaspresso
API	−	+	±	+
	+	−	−	+
	−	+	−	+
	−	±	±	+
	−	±	−	+
	−	−	−	+
adb	+	−	−	+

From this table, the answer should be obvious. If you are just starting to dive into the world of autotesting, the easiest place to start is with Kaspresso. He will solve many problems for you that you will certainly face. It provides a convenient API that includes and extends Kakao, which hides calls to Espresso, UiAutomator, and AdbServer, which greatly expands your capabilities. Last but not least, it contains special extension points so you can get the behavior you want from it.

How to write Android UI tests