滚动固定元素的内容以及父级

Question

Question title might be bit confusing, but please have a look at this fiddle for more info.

I have a container with scrollbar and one element fixed left to it. When I am scrolling I would like to make fixed element content also scrolling. Here is the code

 $('.parent').on('scroll', function(){
   var top = $(this).scrollTop(), _top = $('.right').offset().top;
   $('.left').animate({
      scrollTop : top - _top
   },0)
 });

Please refer to fiddle for demo.

This is working but there is some non uniform scrolling and I am unable to fix it.

Answer 1

I think the extra subtraction of _top is causing the uniformity issue, since it is recalculating the offset top each time, and continually subtracting it.

$('.parent').on('scroll', function(){
    var top = $(this).scrollTop(), _top = $('.right').offset().top;
    $('.left').animate({
        scrollTop : top
    },0)
});

Appears to let the scrolling be more uniform, minus some padding issues.