Fragment 加入动画
参考:http://blog.csdn.net/flowingflying/article/details/12995519
setTransition
FragmentTransaction ft = getFragmentManager().beginTransaction();
ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
setCustomAnimations
ft.setCustomAnimations(R.animator.slide_in_left,R.animator.slide_out_right);