/*
* 
* 指定ブロックの高さを同一に保つスクリプト
*
* Copyright: (c) 2009 dmp.co.jp
**************************************/
var sameHeightGroup = function(){
	var nowHeight = 0;
	var watchElements = [];
	function checkHeight(){
		var groupMaxHeight = 0;
		for (var i = 0; i < watchElements.length; i++) {
			var defHeight = watchElements[i].style.height;
			watchElements[i].style.height = 'auto';
			var tmpHeight = watchElements[i].offsetHeight;
			watchElements[i].style.height = defHeight;
			if (groupMaxHeight < tmpHeight) 
				groupMaxHeight = tmpHeight;
		}
		for (var i = 0; i < watchElements.length; i++) {
			watchElements[i].style.height = groupMaxHeight + "px";
		}
	}
	var functions = {
	addTargetByClass:function (className){
		var elements = document.getElementsByClassName(className);
		for (var i = 0; i < elements.length; i++) {
			watchElements.push(elements[i]);
		}
		checkHeight();
	},
	checkHeight: checkHeight
	}
	setTimeout(
		function(){
			setInterval(functions.checkHeight,1000);
		},
		Math.random()*1000
	);
	
	return functions;
}