scroller.js

/**
 * This file is writen by Georgi Naumov
 * [email protected] for contacts and
 * suggestions.
 **/

/**
 * I try to made a
 * scroller 'object'.
 */
var scroller = (function(){
      var intervalId = null;
      var divToScroll = null;
      var maxScroll = null;

      return {

          startScroll : function() {
              /**
               * Protect from several scroll startups
               */
              if(intervalId != null) {
                  return false;
              }
              divToScroll = document.getElementById("scroller");
              /**
               * 4 - size ot borders for every side.
               **/
              maxScroll = divToScroll.scrollWidth - divToScroll.offsetWidth + 8;
              intervalId = setInterval(function() {
                  if(divToScroll.scrollLeft == maxScroll) {
                      divToScroll.scrollLeft = 0;
                  }
                  divToScroll.scrollLeft += 20;
              }, 500);
          },

          stopScroll : function() {
              /**
               * If intervalId is null we don't
               * need to clear it.
               */
              if(intervalId == null) {
                  return false;
              }
              clearInterval(intervalId);
              intervalId = null;
          }
      }
})();

scroller.startScroll();