Android：Espresso：無法檢查是否成功開始活動

Question

Android Studio 3.2

我有2個活動。 一個活動（ TradersActivity ）具有列表。 每個項目都有按鈕“ Json View ”。 單擊此按鈕（在位置15的項目上）時，然后打開另一個活動JsonViewActivity 。 我想創建Espresso的測試，以檢查單擊此按鈕后是否成功打開新活動JsonViewActivity

這里是Espresso的測試：

import org.hamcrest.CoreMatchers.not
import java.util.*
import org.junit.Rule
import org.junit.Test
import org.junit.runner.RunWith
import androidx.test.espresso.matcher.ViewMatchers.isDisplayed
import android.graphics.Typeface
import android.view.View
import androidx.test.espresso.action.ViewActions.swipeLeft
import androidx.test.espresso.intent.Intents.intended
import androidx.test.espresso.intent.matcher.IntentMatchers.hasComponent
import androidx.test.rule.ActivityTestRule

@RunWith(AndroidJUnit4::class)
class TradersActivityTest {
    @Rule
    @JvmField
    var tradersActivitytRule = ActivityTestRule(TradersActivity::class.java)

    @Test
    fun itemList_viewJsonButton_click_check() {
        //scroll
        onView(withId(R.id.tradersRecyclerView))
                .perform(RecyclerViewActions.scrollToPosition<RecyclerView.ViewHolder>(15));
        // click
        onView(withRecyclerView(R.id.tradersRecyclerView).atPositionOnView(15, R.id.viewJsonButton))
                .perform(click())
        // chekk ist start JsonViewActivity activity
        intended(hasComponent(JsonViewActivity::class.java.getName()))
    }

但是我得到了錯誤：

$ adb shell am instrument -w -r   -e debug false -e class 'com.myproject.android.activity.TradersActivityTest#itemList_viewJsonButton_click_check' com.myproject.android.debug.test/androidx.test.runner.AndroidJUnitRunner
Client not ready yet..
Started running tests

java.lang.NullPointerException: Attempt to invoke virtual method 'void androidx.test.espresso.intent.Intents.internalIntended(org.hamcrest.Matcher, androidx.test.espresso.intent.VerificationMode, java.util.List)' on a null object reference
at androidx.test.espresso.intent.Intents$2.check(Intents.java:194)
at androidx.test.espresso.ViewInteraction$SingleExecutionViewAssertion.check(ViewInteraction.java:419)
at androidx.test.espresso.ViewInteraction$2.call(ViewInteraction.java:282)
at androidx.test.espresso.ViewInteraction$2.call(ViewInteraction.java:268)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

Tests ran to completion.

Answer 1

如果您使用IntentsTestRule而不是ActivityTestRule它將起作用。