@Override
        public CharSequence getPageTitle(int position) {
            switch (position) {
                case 0:
                    return "SECTION 1";
                case 1:
                    return "SECTION 2";
                case 2:
                    return "SECTION 3";
            }
            return null;
        }
A {@link FragmentPagerAdapter} that returns a fragment corresponding to
one of the sections/tabs/pages.
app/src/main/java/home/smart/fly/animations/ui/activity/ViewPagerNestedActivity.java