我在我的 Android (4.0+) 应用 fragment (在 Activity 中)中使用标签栏。
我想创建 Espresso 测试,但如果我创建主 Activity 并打开 fragment 。我得到这个异常:
java.lang.IllegalStateException: ViewPager does not have adapter instance.
at com.astuetz.PagerSlidingTabStrip.setViewPager(PagerSlidingTabStrip.java:177)
at cz.villamemories.detoxme.staticcontent.StaticContentFragment.onCreateView(StaticContentFragment.java:197)
我在 fragment 中的代码:
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
mViewPagerAdapter = new StaticContentPagerAdapter(
this.getChildFragmentManager(), mItemsList, categories);
mPager.setAdapter(mViewPagerAdapter);
mTabs.setViewPager(mPager); //line 197
你有什么地方可能有问题的提示吗?怎么了?
最佳答案
我在 fragment 中也面临着 ViewPager 的问题。这个问题发生在我身上是因为我的 viewpager 有多个根元素。
@RunWith(JUnit4.class)
public class FragmentTest {
private static final String TAG = "FragmentTest";
@Rule
public ActivityTestRule<MainActivity> mActivity = new ActivityTestRule<MainActivity>(MainActivity.class);
@Test
public void checkTabSwiping() {
onView(nthChildOf(withId(R.id.main_content), 5)).check(matches(withId(R.id.homecontentgrouppager)));
}
public static Matcher<View> firstChildOf(final Matcher<View> parentMatcher) {
return new TypeSafeMatcher<View>() {
@Override
public void describeTo(Description description) {
description.appendText("with first child view of type parentMatcher");
}
@Override
public boolean matchesSafely(View view) {
if (!(view.getParent() instanceof ViewGroup)) {
return parentMatcher.matches(view.getParent());
}
ViewGroup group = (ViewGroup) view.getParent();
return parentMatcher.matches(view.getParent()) && group.getChildAt(0).equals(view);
}
};
}
public static Matcher<View> nthChildOf(final Matcher<View> parentMatcher,
final int childPosition){
return new TypeSafeMatcher<View>() {
@Override
public void describeTo(Description description) {
description.appendText("with " + childPosition + " child view of type parentMatcher");
}
@Override
public boolean matchesSafely(View view) {
if (!(view.getParent() instanceof ViewGroup)) {
return parentMatcher.matches(view.getParent());
}
ViewGroup group = (ViewGroup) view.getParent();
return parentMatcher.matches(view.getParent()) && view.equals(group.getChildAt(childPosition));
}
};
}
}
这是我的 homefragment.xml 文件
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:animateLayoutChanges="true"
android:background="@color/black"
android:orientation="vertical">
<android.support.v4.view.ViewPager
android:id="@+id/promotionalviewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"></android.support.v4.view.ViewPager>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="@dimen/size_5"
android:gravity="center_horizontal">
<LinearLayout
android:id="@+id/viewPagerCountDots"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:gravity="center_horizontal"
android:orientation="horizontal" />
</RelativeLayout>
希望对您在 Expresso Framework 中创建测试用例有所帮助。
关于安卓 Espresso : ViewPager does not have adapter instance,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/31023977/