导航抽屉+ ViewPager - 片段不显示

Question

我对我创建的布局有问题.我使用导航抽屉作为主要导航模式.它看起来和我想要的工作,但问题是,在返回到保持的片段后ViewPager- 内部片段未显示.但是,它们会在首次打开应用程序时显示,并默认显示 - ViewPager保留Fragment.

其他导航抽屉Fragments显示正常,所以我不希望我的导航抽屉实现有任何问题

RecordFragment.java(片段持有ViewPager Fragments):

public class RecordFragment extends Fragment {
    private ViewPager mViewPager;

    public RecordFragment() {
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.record_fragment, container, false);
        //getActivity().setTitle(R.string.record);
        return rootView;
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        mViewPager = (ViewPager) view.findViewById(R.id.record_pager);
        FragmentManager manager = getFragmentManager();
        mViewPager.setAdapter(new MyFragmentPagerAdapter(manager));
    }

    class MyFragmentPagerAdapter extends FragmentPagerAdapter {

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

        @Override
        public Fragment getItem(int item) {
            Fragment fragment = null;
            if (item == 0) {

                fragment = new NumbersFragment();
            } else if (item == 1) {

                fragment = new MapFragment();
            }
            return fragment;
        }

        @Override
        public int getCount() {
            return 2;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            String title = new String();
            if (position == 0) {
                title = "Numbers";
            } else if (position == 1) {
                title = "Map";
            }
            return title;
        }

    }
}

NumbersFragment.java(的一个Fragmentsholded者通过RecordFragment)

public class NumbersFragment extends Fragment {
    public NumbersFragment() {
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.numbers_fragment, container, false);
        //getActivity().setTitle(R.string.record);
        return rootView;
    }
}

record_fragment.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">
    <android.support.v4.view.ViewPager
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/record_pager"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <android.support.v4.view.PagerTabStrip
            android:id="@+id/pager_title_strip"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="top"
            android:background="#33b5e5"
            android:textColor="#fff"
            android:paddingTop="4dp"
            android:paddingBottom="4dp" />
    </android.support.v4.view.ViewPager>

</LinearLayout>

Answer 1

你Fragment在另一个中使用s Fragment,在这种情况下你需要使用Fragment#getChildFragmentManager()方法:

FragmentManager manager = getChildFragmentManager();

如果不工作,你可以尝试切换到FragmentStatePagerAdapter替代的FragmentPagerAdapter(但你仍然需要使用儿童片段经理).