fix footer position

I am trying to fix footer at bottom开发者_JS百科 in iPad using the code

$(window).scroll(function(){
   var offsetY = window.pageYOffset;
   var winHeight = $(window).height();
   $('#footer').css({top: (winHeight+offsetY-60)+'px'});   
});

where 60 is the height of footer. Its working fine but while scrolling (untill not finished) the footer's top position does not change, is there any way I can now that scroll has started? so that I can move the footer immediately or hide it while scrolling.

---

you can do this by using only CSS don't use jQuery for that

#footer{
    position:fixed;
    left:0px;
    bottom:0px;
    height:20px;
    width:100%;
    background:#999;
}
/* For ie 6*/
* html #footer{
    position:absolute;
    top:expression((0-(footer.offsetHeight)+(document.documentElement.clientHeight ? document.documentElement.clientHeight : document.body.clientHeight)+(ignoreMe = document.documentElement.scrollTop ? document.documentElement.scrollTop : document.body.scrollTop))+'px');
}