Espresso Test 2: Espresso_simple

Espresso 这个系列的内容的第二篇，代码是参考视频 UI Testing for Beginners (Espresso and androidx.test)

知识点

ActivityScenario.launch

ActivityScenario provides APIs to start and drive an Activity's lifecycle state for testing. It works with arbitrary activities and works consistently across different versions of the Android framework.

说明链接： developer.android.com/reference/a…

withEffectiveVisibility

Returns a matcher that matches Views that have "effective" visibility set to the given value.

Effective visibility takes into account not only the view's visibility value, but also that of its ancestors. In case of ERROR(/View.VISIBLE), this means that the view and all of its ancestors have visibility=VISIBLE. In case of GONE and INVISIBLE, it's the opposite - any GONE or INVISIBLE parent will make all of its children have their effective visibility.

Note: Contrary to what the name may imply, view visibility does not directly translate into whether the view is displayed on screen (use isDisplayed() for that). For example, the view and all of its ancestors can have visibility=VISIBLE, but the view may need to be scrolled to in order to be actually visible to the user. Unless you're specifically targeting the visibility value with your test, use isDisplayed().

链接： developer.android.com/reference/a…

withText

Returns a matcher that matches TextViews based on text property value.

Note: A View text property is never null. If you call TextView.setText(CharSequence) with a null value it will still be "" (empty string). Do not use a null matcher.

链接：developer.android.com/reference/a…

ActivityScenarioRule

ActivityScenarioRule launches a given activity before the test starts and closes after the test.

链接：developer.android.com/reference/a…

1. Espresso 依赖

dependencies {

    implementation 'androidx.core:core-ktx:1.7.0'
    implementation 'androidx.appcompat:appcompat:1.4.2'
    implementation 'com.google.android.material:material:1.4.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
    testImplementation 'junit:junit:4.13.2'

    androidTestImplementation 'androidx.test.ext:junit:1.1.3'

    // Espresso
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'

2. 创建的页面

创建的页面有两个，一个是 MainActivity 和 SecondActivity

• MainActivity

这个页面只有一个 TextView 和一个 Button

• SecondActivity

这个页面只有一个 TextView 和一个 Button

具体的代码已经放到 Github 上 github.com/yxhuangCH/E…

3. 创建测试代码

MainActivityTest

@RunWith(AndroidJUnit4ClassRunner::class)
class MainActivityTest{

   @Test
   fun test_activity_inView() {
       val activityScenario = ActivityScenario.launch(MainActivity::class.java)

       onView(withId(R.id.main)).check(matches(isDisplayed()))
   }

   @Test
   fun testVisibility_title_nextButton() {
       val activityScenario = ActivityScenario.launch(MainActivity::class.java)

       // 方法 1
       onView(withId(R.id.activity_main_title))
           .check(matches(isDisplayed()))

       // 方法 2
       onView(withId(R.id.activity_main_title))
           .check(matches(withEffectiveVisibility(Visibility.VISIBLE)))

       onView(withId(R.id.button_next_activity))
           .check(matches(isDisplayed()))
   }

   @Test
   fun testTitleTextDisplayed() {
       val activityScenario = ActivityScenario.launch(MainActivity::class.java)

       onView(withId(R.id.activity_main_title))
           .check(matches(withText(R.string.text_mainactivity)))

   }
}

MainActivityTest 通过 ActivityScenario.launch 启动一个 Activity

• test_activity_inView

  测试页面已经展示

• testVisibility_title_nextButton

  测试 title 和 button 显示。其中 withEffectiveVisibility 函数也是可以判断 View 及其祖先 View 是否都是可见状态。 方法 1 和 方法 2 是等价。

• testTitleTextDisplayed

  通过 withText 测试 title 的展示的文案和 R.string.text_mainactivity 一致