gistfile1.js

function CssAnimationClass(element, cssClassName, callback) {
	this.animationEndEventString = userAgent == WEBKIT ? 'webkitAnimationEnd' :
    (goog.userAgent.OPERA ? 'oAnimationEnd' : 'animationend');
	
	this.element = element;
	this.cssClassName = cssClassName;
	this.callback = callback;
}

CssAnimationClass.prototype.play = function() {
	this.element.addEventListener(this.animationEndEventString, this.handleAnimationEnd.bind(this)) //Function.prototype.bind() is supported from Javascript 1.8.5
	this.element.className = this.cssClassName;
}

CssAnimationClass.prototype.handleAnimationEnd = function() {
	this.callback();
}