Breaking Change in FragmentTransaction at Support Library 25.1.0

In support library 25.1.0, Fragment's life cycle has been changed when replacing Fragments.

D/FragmentA: onStart()
D/FragmentA: onResume()
D/FragmentB: onStart()
D/FragmentB: onResume()
D/FragmentA: onPause()
D/FragmentA: onStop()

Issue 230415

This is an intended behavior change. You can use FragmentTransaction#setAllowOptimization(false) if you prefer the past behavior.

getFragmentManager()
        .beginTransaction()
        .setAllowOptimization(false) // opt-out
        .replace(R.id.container, FragmentA.newInstance(), FragmentA.class.getSimpleName())
        .commit();

FragmentTransaction's behavior reverted as of Support Library 25.1.1

As of support library 25.1.1, setAllowOptimization(flag) is default to false.

You can use .setAllowOptimization(true) only when you need optimization.

getFragmentManager()
        .beginTransaction()
        .setAllowOptimization(true) // opt-in
        .replace(R.id.container, FragmentA.newInstance(), FragmentA.class.getSimpleName())
        .commit();