code: public void setPagerTransformer(boolean reverseDrawingOrder,BaseTransformer transformer){
          mViewPagerTransformer = transformer;
          mViewPagerTransformer.setCustomAnimationInterface(mCustomAnimation);
          mViewPager.setPageTransformer(reverseDrawingOrder,mViewPagerTransformer);
      }
docs: set ViewPager transformer.
  @param reverseDrawingOrder
  @param transformer