SectionsPagerAdapter.java

 public class SectionsPagerAdapter extends FragmentPagerAdapter {

        private final List<Fragment> mFragmentList = new ArrayList<>();
        private final List<String> mFragmentTitleList = new ArrayList<>();

        public SectionsPagerAdapter(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, int position) {
            mFragmentList.add(position, fragment);
            mFragmentTitleList.add(position, title);
        }

        public void removeFragment(Fragment fragment, int position) {
            mFragmentList.remove(position);
            mFragmentTitleList.remove(position);
        }

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


    }