jquery welches div gerade angezeigt

by Cheffchen

HTML

<div class="span4">xxx</div>
<div class="span4">xxx</div>
<div class="span4">xxx</div>
<div class="span4">xxx</div>
<div class="span4">xxx</div>
<div class="span4">xxx</div>

CSS

.span4 {height:200px;}

JavaScript

$(function() {
  i=0;
  var gruppen = [];
    $('.span4').each(function(e){  
      gruppen.push($(this).offset().top);  
    });

    
//gruppen.reverse();
 var Zahlenkette = gruppen.join(" ");alert(Zahlenkette);
    
function scrollTrackPageview(){
    $.each(gruppen, function(key,value) { 
        if($(window).scrollTop() <= value){
            $('.span4').html(key+' Etage');
            return false;
        }
    return true;
    });    
}   
$(window).on("scroll", scrollTrackPageview);    
});