Why the RecyclerView items disappear when the transition animation start from one fragment to another?

I have a recyclerview items inside a fragment when I click on an item from the recyclerview it repleces the olde fragment with a new one. And i have an animation going when the transition happens like this:

FragmentTransaction ft = activity.getSupportFragmentManager().beginTransaction();                   
ft.setCustomAnimations(R.anim.slide_out_top,R.anim.slide_in_top);
ft.replace(R.id.container, AnotherFragment.newInstance());
ft.comit;