//sidebar滚动
var mymovey = new Number();
function floatIM()
{
	var floatLayer=document.getElementById('im');
	if (!floatLayer) return false;
	window.setInterval("heartBeat()",1);
}

function heartBeat(){
	diffY=getPageScrollTop();
	mymovey += Math.floor((diffY-document.getElementById('im').style.top.replace("px","")-50)*0.1);
	document.getElementById('im').style.top = mymovey+"px";
}

function getPageScrollTop(){
	var yScrolltop;
	if (self.pageYOffset) {
		yScrolltop = self.pageYOffset;
	} else if (document.documentElement && document.documentElement.scrollTop){	 // Explorer 6 Strict
		yScrolltop = document.documentElement.scrollTop;
	} else if (document.body) {// all other Explorers
		yScrolltop = document.body.scrollTop;
	}
	arrayPageScroll = yScrolltop;
	return arrayPageScroll;
}

function switchTag(whichId){
	var whichId=document.getElementById(whichId);
	if (!whichId) return false;
	var tag=whichId.getElementsByTagName('h3')[0].getElementsByTagName('span');
	for (var i=0;i<tag.length;i++){
		switchBox(whichId,i);
	}
}

function switchBox(whichId,whichTag){
	if (!whichId) return false;
	var tag=whichId.getElementsByTagName('h3')[0].getElementsByTagName('span');
	var box=whichId.getElementsByTagName('ul');
	tag[whichTag].onmouseover=function(){
		for (var i=0;i<tag.length;i++){
			tag[i].className='';
			if (box[i]){
				box[i].className='hidden';
			}
			tag[i].onclick=function(){
				return false;
			}
		}
		this.className='hover';
		if (box[whichTag]){
			box[whichTag].className='';
		}
	}
}


//监听事件
function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}

addLoadEvent(floatIM);
addLoadEvent(function(){switchTag('linker')});