// JavaScript Document

/*初始化一级菜单背景图片*/
function initMenuBg()
{
	var oLi=document.getElementById("menu").getElementsByTagName("li");
	for(i=0;i<oLi.length;++i)
	{
		//对一级菜单li加背景图片
		if(oLi[i].parentNode.parentNode.nodeName!="LI")
		{
			oLi[i].style.backgroundImage="url(../images/menu1link.gif)";
			oLi[i].style.backgroundRepeat="no-repeat";
		}		
	}
	specialMenu();
}

/*初始化二级菜单背景图片*/
function initMenu2Bg()
{
	var oLi=document.getElementById("menu").getElementsByTagName("li");
	for(i=0;i<oLi.length;++i)
	{
		//对二级菜单li加背景图片
		if(oLi[i].parentNode.parentNode.nodeName=="LI")
		{
			oLi[i].style.backgroundImage="url(../images/menu2link.gif)";
			oLi[i].style.backgroundRepeat="no-repeat";
		}		
	}
	specialMenu();
	special2Menu();
}

function showSubMenu(obj)
{
	if(gobj!=obj)
	{
		gobj.style.backgroundImage="url(../images/menu1link.gif)";
		gobj.style.backgroundRepeat="no-repeat";
		//保存前一个单击对象
		gobj=obj;
		//隐藏所有二级菜单
		var oUl=document.getElementById("menu").getElementsByTagName("ul");
		for(i=0;i<oUl.length;++i)
		{
			oUl[i].style.display="none";
		}
		//打开obj对象二级菜单
		var oTemp=obj.getElementsByTagName("ul")[0];
		oTemp.style.display="block";
	}
}

//改变选中一级菜单的背景图片
function showHover(obj)
{
	initMenuBg();
	obj.style.backgroundImage="url(../images/menu1hover.gif)";
	obj.style.backgroundRepeat="no-repeat";
}

//改变选中二级菜单的背景图片
function show2Hover(obj)
{
	initMenu2Bg();
	obj.style.backgroundImage="url(../images/menu2hover.gif)";
	obj.style.backgroundRepeat="no-repeat";	
}

function showLink(obj)
{
	if(obj!=gobj)
	{	
		obj.style.backgroundImage="url(../images/menu1link.gif)";
		obj.style.backgroundRepeat="no-repeat";
	}
}