安卓ViewPager : Recursive entry to executePendingTransactions with no nested fragments

Question

我在我的应用程序上使用 ViewPager，它工作正常，只是显示最后一个 fragment 。当显示该 fragment 时，我收到以下错误:

java.lang.IllegalStateException: Recursive entry to executePendingTransactions
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1388)
at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:431)
at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:139)
at android.support.v4.view.ViewPager.populate(ViewPager.java:804)
at android.support.v4.view.ViewPager.completeScroll(ViewPager.java:1280)
at android.support.v4.view.ViewPager.computeScroll(ViewPager.java:1176)
at android.view.View.getDisplayList(View.java:14182)
at android.view.View.getDisplayList(View.java:14239)
at android.view.View.draw(View.java:15017)
at android.view.ViewGroup.drawChild(ViewGroup.java:3298)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:3135)
at android.view.View.getDisplayList(View.java:14192)
at android.view.View.getDisplayList(View.java:14239)
at android.view.View.draw(View.java:15017)
at android.view.ViewGroup.drawChild(ViewGroup.java:3298)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:3135)
at android.view.View.draw(View.java:15306)
at android.widget.FrameLayout.draw(FrameLayout.java:472)
at android.view.View.getDisplayList(View.java:14197)
at android.view.View.getDisplayList(View.java:14239)
at android.view.View.draw(View.java:15017)
at android.view.ViewGroup.drawChild(ViewGroup.java:3298)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:3135)
at android.view.View.getDisplayList(View.java:14192)
at android.view.View.getDisplayList(View.java:14239)
at android.view.View.draw(View.java:15017)
at android.view.ViewGroup.drawChild(ViewGroup.java:3298)
at android.view.ViewGroup.dispatchDraw(ViewGroup.java:3135)
at android.view.View.draw(View.java:15306)
at android.widget.FrameLayout.draw(FrameLayout.java:472)
at com.android.internal.policy.impl.PhoneWindow$DecorView.draw(PhoneWindow.java:2568)
at android.view.View.getDisplayList(View.java:14197)
at android.view.View.getDisplayList(View.java:14239)
at android.view.HardwareRenderer$GlRenderer.buildDisplayList(HardwareRenderer.java:1570)
at android.view.HardwareRenderer$GlRenderer.draw(HardwareRenderer.java:1449)
at android.view.ViewRootImpl.draw(ViewRootImpl.java:2705)
at android.view.ViewRootImpl.performDraw(ViewRootImpl.java:2571)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2143)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1234)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6467)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:803)
at android.view.Choreographer.doCallbacks(Choreographer.java:603)
at android.view.Choreographer.doFrame(Choreographer.java:573)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:789)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5356)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
at dalvik.system.NativeStart.main(Native Method)

阅读几个 stackoverflow 问题，最常见的原因是有嵌套的 fragment 。但是，这不是我的情况，我的 fragment 都不包含子 fragment 。为了填充 ViewPager，我使用了 PageAdapter，如下所示:

    // step 1: create the fragment list
    List<Fragment> fragments = new Vector<Fragment>();
    // wt1
    WalkthroughFragment fragment = new WalkthroughFragment_();
    fragment.setImageBottomId(R.drawable.wt1);
    fragment.setTextId(R.string.walkthrough_1);
    fragment.setButtonId(R.string.walkthrough_skip);
    fragments.add(fragment);
    // wt2
    fragment = new WalkthroughFragment_();
    fragment.setImageBottomId(R.drawable.wt2);
    fragment.setTextId(R.string.walkthrough_2);
    fragments.add(fragment);
    // login
    LoginSocialFragment social = new LoginSocialFragment_();
    fragments.add(social);

    // step 2: create the adapter for the view pager
    this.pager.setAdapter(new MyPageAdapter(getSupportFragmentManager(), fragments));
    // step 3: set the default item as the first one
    //TODO: use preferences to see whether should be the last one
    this.pager.setCurrentItem(0);
    //step 4: bind the pager to the indicator
    this.indicator.setViewPager(this.pager);
    this.indicator.notifyDataSetChanged();

然后我不会在代码的任何其他部分使用这些 fragment ，也不会再次添加它们。有什么想法吗？

Answer 1

最终是最后一个 fragment 的问题。当 ViewPager 加载该 fragment 时，由于缺少 jar，它抛出了 ClassDefNotFound 异常。然后，由于我正在重新加载 Activity ，该 fragment 再次被实例化并且未能抛出我在帖子中提出的异常。因此，“executePendingTransactions 的递归条目”异常并不总是与嵌套 fragment 有关。只是想让你知道:)