视图在返回选项卡片段时不会膨胀

View is not inflated on returning to the tab fragment

我有一个 activity 名为 rootActivity ,其中我有一个 rootContainer,我在其中替换片段。

现在,我替换的第一个片段是 DashboardFragment。

我现在点击十字打开一个像这样的新片段... 现在,当我按下后退按钮时,仪表板片段的内容丢失了。

谁能帮帮我

这里有一段视频展示了真实情况。 https://youtu.be/NobqYUCEZKY

DashboardFragment(包含选项卡内的片段)的代码

public class DashboardFragment extends Fragment {
    private Toolbar toolbar;
    private TabLayout tabLayout;
    private ViewPager viewPager;
    private View rootView;

    /**
     *
     * @param config : For setting up stuff by the given config
     * @return
     */
    public static DashboardFragment newInstance(Bundle config) {

        DashboardFragment fragment = new DashboardFragment();
        fragment.setArguments(config);
        return fragment;
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        rootView = inflater.inflate(R.layout.activity_dashboard, container, false);
        toolbar = (Toolbar) rootView.findViewById(R.id.toolbar);
        ((RootActivity)getActivity()).setSupportActionBar(toolbar);

        viewPager = (ViewPager) rootView.findViewById(R.id.viewpager);
        setupViewPager(viewPager);

        tabLayout = (TabLayout) rootView.findViewById(R.id.tabs);
        tabLayout.setupWithViewPager(viewPager);
        setupTabIcons();

        return rootView;
    }

    private void setupTabIcons() {
        tabLayout.getTabAt(0).setIcon(android.R.drawable.btn_star_big_off);
        tabLayout.getTabAt(1).setIcon(android.R.drawable.btn_star_big_on);
    }

    private void setupViewPager(ViewPager viewPager) {
        ViewPagerAdapter adapter = new ViewPagerAdapter(getActivity().getSupportFragmentManager());
        adapter.addFragment(new TrackeesFragment(), "Trackee");
        adapter.addFragment(new TrackersFragment(), "Trackers");
        viewPager.setAdapter(adapter);
    }

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

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

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

        @Override
        public int getCount() {
            return mFragmentList.size();
        }

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

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            return super.instantiateItem(container, position);
        }

        @Override
        public CharSequence getPageTitle(int position) {
            return null;
        }
    }
}

尝试更改

中的以下行
setupViewPager(ViewPager viewPager) {}

改变

ViewPagerAdapter adapter = new ViewPagerAdapter(getActivity().getSupportFragmentManager());

ViewPagerAdapter adapter = new ViewPagerAdapter(getChildFragmentManager());