var doc = document;

function eleId(id) {
	if (doc.getElementById(id)) {
		return doc.getElementById(id);
	}
	return false;
}
function focusOn(id) {
	if (eleId(id)) {
		eleId(id).focus();
	}
}
function getEvent(e) {
	return (!e ? window.event : e);
}
function getEventTarget(e) {
	var targ;
	var e = getEvent(e);
	if (e.target) {
		targ = e.target;
	} else if (e.srcElement) {
		targ = e.srcElement;
	}
	
	// defeat Safari bug
	if (targ.nodeType == 3) {
		targ = targ.parentNode;
	}
	
	return targ;
}
function addEvent(obj, type, fn) {
	if (obj.addEventListener) {
		obj.addEventListener(type, fn, false);
	} else if (obj.attachEvent) {
		obj["e"+type+fn] = fn;
		obj[type+fn] = function() { obj["e"+type+fn]( window.event ); }
		obj.attachEvent( "on"+type, obj[type+fn] );
	}
}
function removeEvent(obj, type, fn) {
	if (obj.removeEventListener) {
		obj.removeEventListener( type, fn, false );
	} else if (obj.detachEvent) {
		obj.detachEvent( "on"+type, obj[type+fn] );
		obj[type+fn] = null;
		obj["e"+type+fn] = null;
	}
}
function setOpacity(ele, val) {
	ele.style.opacity = val/10;
	ele.style.filter = 'alpha(opacity='+val*10+')';
}
function addTransparentPng(ele, id, img) {
	ele = (ele ? ele : eleId(id));
	
	if(typeof ele.style.filter !='undefined' ) {
		ele.style.filter = 'progid:DXImageTransform.Microsoft.AlphaImageLoader(src=\''+img+'\', sizingMethod=\'image\')';
	} else {
		ele.style.backgroundImage = 'url('+img+')';
	}
}