code: public void setCustomAnimation(BaseAnimationInterface animation){
          mCustomAnimation = animation;
          if(mViewPagerTransformer != null){
              mViewPagerTransformer.setCustomAnimationInterface(mCustomAnimation);
          }
      }
docs: Inject your custom animation into PageTransformer, you can know more details in
  {@link com.daimajia.slider.library.Animations.BaseAnimationInterface},
  and you can see a example in {@link com.daimajia.slider.library.Animations.DescriptionAnimation}
  @param animation