ViewPagerFragment.java

public class ViewPagerFragment extends Fragment {

    public static final String PAGE_TITLE = "Tab1";

    ViewPager viewPager;
    ViewPagerAdapter viewPagerAdapter;

    public ViewPagerFragment() {
        // Required empty public constructor
    }

    /**
     * Use this factory method to create a new instance of
     * this fragment
     * @return A new instance of fragment ViewPagerFragment.
     */
    public static ViewPagerFragment newInstance() {
        ViewPagerFragment fragment = new ViewPagerFragment();
        return fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View view = inflater.inflate(R.layout.fragment_view_pager, container, false);

        viewPager = (ViewPager) view.findViewById(R.id.viewpager);
        viewPagerAdapter = new ViewPagerAdapter(getChildFragmentManager());
        viewPager.setAdapter(viewPagerAdapter);
        return view;
    }


    public static class ViewPagerAdapter extends FragmentStatePagerAdapter {
        private static final int NUM_ITEMS = 2;

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

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

        @Override
        public Fragment getItem(int position) {
            if(position == 0){
                return InnerViewPager.newInstance();
            }
            else {
                return Fragment2.newInstance();
            }
        }

        @Override
        public CharSequence getPageTitle(int position) {

            if(position == 0){
                return ViewPagerFragment.PAGE_TITLE;
            }
            else {
                return Fragment2.PAGE_TITLE;
            }
        }
    }
}