/*-----------------------------------------------------------
 Original
 http://archiva.jp/web/javascript/tab-menu.html

 Customized by WWW WATCH
 http://hyper-text.org/archives/2007/09/javascript_tab.shtml
------------------------------------------------------------*/
var tid;

/*--setup--*/
window.onload=function() {
	tabmenu.setup = {
		tabs: document.getElementById('mainNav').getElementsByTagName('li'),

		pages: [
			document.getElementById('home'),
			document.getElementById('about'),
			document.getElementById('join'),
			document.getElementById('activity'),
			document.getElementById('material')
		]
	}

tabmenu.init();

//

}
/*--setup end--*/
var tabmenu = {
	init: function(){
		var tabs = this.setup.tabs;
		var pages = this.setup.pages;
		for(i=0; i<pages.length; i++) {
		if(i !== 0) pages[i].style.display = 'none';         
			tabs[i].onmouseover = function(){ tabmenu.showpage(this); return false; };
			tabs[i].onmouseout = function(){ clearTimeout(tid); return false; };
			tabs[i].onclick = function(){ tabmenu.showpage(this); return false; };
		}
	},

	showpage: function(obj){
		var tabs = this.setup.tabs;
		var pages = this.setup.pages;
		var num;
		for(num=0; num<tabs.length; num++) {
			if(tabs[num] === obj) break;
		}
		tid=setTimeout(function(){afterShow(pages,tabs,num)},200);
	}
}

function afterShow(pages_obj,tabs_obj,num){
	for(var i=0; i<pages_obj.length; i++) {
		if(i == num) {
			pages_obj[num].style.display = 'block';
			tabs_obj[num].className = 'selected';
		}else{
			pages_obj[i].style.display = 'none';
			tabs_obj[i].className = null;
		}
	}
}