Android navigation component: how save fragment state

Question

I use bottomNavigationView and navigation component. Please tell me how I don\'t destroy the fragment after switching to another tab and return to the old one? For example I

Answer 1

Declare fragment on the activity & create fragment instance on onCreate method, then pass the fragment instance in updateFragment method. Create as many fragment instances as required corresponding to bottom navigation listener item id.

Fragment fragmentA;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_home);

fragmentA = new Fragment();
updateFragment(fragmentA);
}

public void updateFragment(Fragment fragment) {
FragmentTransaction transaction = 
getSupportFragmentManager().beginTransaction();
transaction.add(R.id.layoutFragment, fragment);
transaction.commit();
}

Furthermore be sure you are using android.support.v4.app.Fragment and calling getSupportFragmentManager()