How to save data when fragment in BottomNavigationView is changed?

Question

In my app, I use BottomNavigationView and on each fragment I have some elements. On changing fragments my data that download is lost. How can I solve it?

Answer 1

You can use ViewPager.setOffscreenPageLimit() like this:

ViewPager pager = (ViewPager) findViewById(R.id.viewPager);
pager.setOffscreenPageLimit(2); //2 is number of pages that you want keep in memory and don't load again on click at its item.