我在Fragment中有TabLayout，然后使用FragmentTransaction从Main Activity到Fragment

Question

我在Fragment中有TabLayout，然后使用FragmentTransaction从Main Activity到Fragment，但是当从Activity到Fragment的事务显示出这个问题时。

    toolbar = (Toolbar) view.findViewById(R.id.Toolbar);
    ((AppCompatActivity)getActivity()).setSupportActionBar(toolbar);
    // setSupportActionBar(toolbar);

// getSupportActionBar（）。setDisplayHomeAsUpEnabled（true）;

    viewPager = (ViewPager)view. findViewById(R.id.viewpager1);
    setupViewPager(viewPager);

    tabLayout = (TabLayout) view.findViewById(R.id.tabs);
    tabLayout.setupWithViewPager(viewPager);
    //  setupTabIcons();
   return view;
}

// Add Fragments to Tabs
private void setupViewPager(ViewPager viewPager) {
    ViewPagerAdapter adapter = new ViewPagerAdapter(getChildFragmentManager());
 // ViewPagerAdapter adapter = new ViewPagerAdapter(getActivity().getFragmentManager());
    adapter.addFrag(new AllFragment() ,"All");
    adapter.addFrag(new ManFragment(),"Man");
    adapter.addFrag(new WomenFragment(),"Women");
    adapter.addFrag( new KidsFragment(),"Kids");
    viewPager.setAdapter(adapter);
}

class ViewPagerAdapter extends FragmentPagerAdapter {
    private final List<Fragment> mFragmentList = new ArrayList<>();
    private final List<String> mFragmentTitleList = new ArrayList<>();

    public ViewPagerAdapter(FragmentManager manager) {
        super(manager);
    }

    @Override
    public android.support.v4.app.Fragment getItem(int position) {
        return mFragmentList.get(position);
    }

    @Override
    public int getCount() {

        return mFragmentList.size();
    }

    public void addFrag(Fragment fragment, String title) {
        mFragmentList.add(fragment);
        mFragmentTitleList.add(title);
    }

    @Override
    public CharSequence getPageTitle(int position) {

        return mFragmentTitleList.get(position);
    }
}

MainActivivty：