jquery - 在某个点停止固定位置滚动？

Question

我有一个 position:fixed 元素，因此它会随页面滚动，但我希望它按照我想要的方式滚动。当用户向上滚动时我希望元素在某个点停止滚动，比如当它距离页面顶部 250px 时，这可能吗？任何帮助或建议都会有所帮助，谢谢!

我觉得我需要使用 jquery 来做到这一点。我尝试获取用户所在位置的滚动或位置，但真的很困惑，是否有任何 jquery 解决方案？

Answer 1

你是说有点像这样吗？

http://jsfiddle.net/b43hj/

$(window).scroll(function(){
    $("#theFixed").css("top", Math.max(0, 250 - $(this).scrollTop()));
});

$(window).scroll(function(){
    $("#theFixed").css("top", Math.max(0, 100 - $(this).scrollTop()));
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>

<div id="theFixed" style="position:fixed;top:100px;background-color:red">SOMETHING</div>

<!-- random filler to allow for scrolling -->
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