ObjectAnimator in API Level < 11
I suggest using http://nineoldandroids.com/ , its from the same maker of the ActionBarSherlock project, it introduces a support ObjectAnimator that works from API 1 onwards.
Property Animation Introduced in Android 3.0 (API level 11)
For support lower android version, (I didn't try it, but you can use)
Android library for using the Honeycomb (Android 3.0) animation API on all versions of the platform back to 1.0!.
Also Look at this blog Fragment Transactions Reference
and this SO question Android Fragment standard transition not animating