shrukul

        getSupportFragmentManager().addOnBackStackChangedListener(new FragmentManager.OnBackStackChangedListener() {

            ValueAnimator anim;

            @Override
            public void onBackStackChanged() {
                if (getSupportFragmentManager().getBackStackEntryCount() > 0) {
//                    getSupportActionBar().setDisplayHomeAsUpEnabled(true); // show back button

                    anim = ValueAnimator.ofFloat(0, 1);