java.lang.IllegalStateException: Fragment no longer exists for key f1: index 3

Question

I want to understand this exception in order to implement a proper fix.

There\'s a ViewPager and it uses a FragmentStatePagerAdapter to instantiate 2 fragments via g

Answer 1

Use Activity lifeCycle instead of Fragment.

public class MyAdapter extends FragmentStateAdapter {

    public MyAdapter (@NonNull Fragment fragment) {
        super(fragment.getFragmentManager(), fragment.getActivity().getLifecycle());
    }
}

Or as others mentioned disable the ViewPager2 save state.

• in Layout: android:saveEnabled="false"
• in code:
  • viewPager.setSaveEnabled(false);
  • viewPager.setSaveFromParentEnabled(false);