Expresso的Android测试偏好片段

Question

我在用Expresso测试代码时遇到了问题。我写了这个代码：

public class SettingsActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    getFragmentManager().beginTransaction()
            .replace(android.R.id.content, new SettingsFragment())
            .commit();
}

public class SettingsFragment extends PreferenceFragment {
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    addPreferencesFromResource(R.xml.preferences);
}

XML:

<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/preferences_xml">
<PreferenceCategory
  android:title="@string/application_settings"
  android:id="@+id/application_settings_preferences">
<CheckBoxPreference
    android:key="@string/key_processing_private_data_preference"
    android:title="@string/title_processing_private_data_preference"
    android:summary="@string/summary_processing_private_data_preference"
    android:defaultValue="true"
    android:dependency="@string/key_recording_audio_preference"
    android:id="@+id/private_data_check_box_preference"/>
</PreferenceCategory>
 <PreferenceCategory
  android:title="@string/device_settings"
  android:id="@+id/device_settings_preferences">
<CheckBoxPreference
    android:key="@string/key_recording_audio_preference"
    android:title="@string/title_recording_audio_preference"
    android:summary="@string/summary_recording_audio_preference"
    android:defaultValue="true"
    android:id="@+id/recording_audio_check_box_preference"/>
  </PreferenceCategory>
</PreferenceScreen>

我的测试规则：

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

我尝试先测试复选框：

onData(anything())
            .inAdapterView(allOf(
                    isDescendantOfA(withId(R.id.preferences_xml)),
                    withId(R.id.application_settings_preferences)))
            .atPosition(1)
            .check(matches(isDisplayed()));

测试总是失败，NoMatchingViewException：层次结构中找不到匹配的视图：

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我也尝试过：

String workingInBackgroundSummary = mActivityRule.getActivity().getBaseContext().getString(R.string.summary_working_in_background_preference);
   onData(withSummaryText(workingInBackgroundSummary)).check(matches(isDisplayed())); 

测试总是失败，出现NullPointerException：

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onView(withId(R.id.working_in_background_check_box_preference)).check(matches(isDisplayed()));

也会因NoMatchingViewException而失败。

有人会用正确的测试用例来展示一个例子吗？

Answer 1

（代表OP发布）。

已解决：

onData(allOf(
            is(instanceOf(Preference.class)),
            withKey(key),
            withSummary(R.string.summary_working_in_background_preference),
            withTitle(R.string.title_working_in_background_preference)))
            .onChildView(withText(title))
            .check(matches(isCompletelyDisplayed()));