Attempt to invoke virtual method 'int me.yokeyword.fragmentation.anim.FragmentAnimator.getEnter()' on a null object reference

viewpage 使用FragmentStatePagerAdapter，点击position-1出现

java.lang.NullPointerException: Attempt to invoke virtual method 'int me.yokeyword.fragmentation.anim.FragmentAnimator.getEnter()' on a null object reference at me.yokeyword.fragmentation.helper.internal.AnimatorHelper.initEnterAnim(AnimatorHelper.java:63) at me.yokeyword.fragmentation.helper.internal.AnimatorHelper.notifyChanged(AnimatorHelper.java:29) at me.yokeyword.fragmentation.helper.internal.AnimatorHelper.<init>(AnimatorHelper.java:24) at me.yokeyword.fragmentation.SupportFragmentDelegate.onCreate(SupportFragmentDelegate.java:117) at xxx.BaseFragment.onCreate(BaseFragment.java:69) at xxx.ChannelFragment.onCreate(ChannelFragment.java:80) at android.support.v4.app.Fragment.performCreate(Fragment.java:2246) at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1377) at android.support.v4.app.FragmentTransition.addToFirstInLastOut(FragmentTransition.java:1187) at android.support.v4.app.FragmentTransition.calculateFragments(FragmentTransition.java:1070) at android.support.v4.app.FragmentTransition.startTransitions(FragmentTransition.java:115) at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2374) at android.support.v4.app.FragmentManagerImpl.removeRedundantOperationsAndExecute(FragmentManager.java:2332) at android.support.v4.app.FragmentManagerImpl.execSingleAction(FragmentManager.java:2209) at android.support.v4.app.BackStackRecord.commitNowAllowingStateLoss(BackStackRecord.java:649) at android.support.v4.app.FragmentStatePagerAdapter.finishUpdate(FragmentStatePagerAdapter.java:167) at android.support.v4.view.ViewPager.populate(ViewPager.java:1238) at android.support.v4.view.ViewPager.setCurrentItemInternal(ViewPager.java:663) at android.support.v4.view.ViewPager.setCurrentItemInternal(ViewPager.java:625) at android.support.v4.view.ViewPager.setCurrentItem(ViewPager.java:606) at android.support.design.widget.TabLayout$ViewPagerOnTabSelectedListener.onTabSelected(TabLayout.java:2170) at android.support.design.widget.TabLayout.dispatchTabSelected(TabLayout.java:1165) at android.support.design.widget.TabLayout.selectTab(TabLayout.java:1158) at android.support.design.widget.TabLayout.selectTab(TabLayout.java:1128) at android.support.design.widget.TabLayout$Tab.select(TabLayout.java:1427) at android.support.design.widget.TabLayout$TabView.performClick(TabLayout.java:1537) at android.view.View$PerformClick.run(View.java:23645) at android.os.Handler.handleCallback(Handler.java:751) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:154) at android.app.ActivityThread.main(ActivityThread.java:6646) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1468) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1358)

[timmy008]

问题找到了，我自己的代码问题，我起实现ISupportFragment这个接口，Fragment生命周期方法没有去重写，只重写了你这个接口里面的方法

[timmy008]

` mPagerAdapter = new MyPagerAdapter(mActivity.getSupportFragmentManager()); viewPager.setAdapter(mPagerAdapter); tabLayout.setTabMode(TabLayout.MODE_SCROLLABLE); tabLayout.setupWithViewPager(viewPager);

    mWebApi.channels()
                    .subscribeOn(Schedulers.io())
                    .observeOn(AndroidSchedulers.mainThread())
                    .doOnSubscribe(() -> mStatusLayout.showLoading())
                    .subscribe(this::onSuccess, error -> mStatusLayout.showRetry(), () -> 
                    mStatusLayout.showContent()));

 private void setData(List<ChannelsInfo.ColumnListBean> columnList){
             mPagerAdapter.setNewData(columnList);
}

`

` public class MyPagerAdapter extends FragmentPagerAdapter {

private List<ChannelsInfo.ColumnListBean> mTitles = new ArrayList<>();

public MyPagerAdapter(FragmentManager fm) {
    super(fm);
}

@Override
public Fragment getItem(int position) {
    if (position == 0) {
        return HomeRecommendFragment.newInstance();
    } else {
        return ChannelFragment.getInstance(position);
    }
}

@Override
public CharSequence getPageTitle(int position) {
    return mTitles.get(position).getContent();
}

@Override
public int getCount() {
    return mTitles == null ? 0 : mTitles.size();
}


public void setNewData(List<ChannelsInfo.ColumnListBean> titleList) {
    mTitles.clear();
    mTitles = new ArrayList<>(titleList);
    notifyDataSetChanged();
}

} `

大致逻辑是这样的