code: public void setSliderTransformDuration(int period,Interpolator interpolator){
          try{
              Field mScroller = ViewPagerEx.class.getDeclaredField("mScroller");
              mScroller.setAccessible(true);
              FixedSpeedScroller scroller = new FixedSpeedScroller(mViewPager.getContext(),interpolator, period);
              mScroller.set(mViewPager,scroller);
          }catch (Exception e){
  
          }
      }
docs: set the duration between two slider changes.
  @param period
  @param interpolator