Transition detector constructor. Detects when an element had a transition and executes a callback when it ends.

transition.js

var Transition = (function (){
  var transitionEvent = (function whichTransitionEvent(){
    var t, el = document.createElement("fakeelement")
    ,transitions = {
      "WebkitTransition": "webkitTransitionEnd",
      "MozTransition": "transitionend",
      "OTransition": "oTransitionEnd",
      "transition": "transitionend"
    };
 
    for (t in transitions){
      if (el.style[t] !== undefined) return transitions[t];
    }
  })();
 
  function Transition(elem){
    this.elem = elem;
    // this.options = {
    //   autoChangeState: true
    // };
    elem.addEventListener(transitionEvent, function (){
      this.isExecuting = false;
      return this.onTransitionEnd && this.onTransitionEnd();
    }.bind(this));
  }
  Object.defineProperties(Transition.prototype, {
    'start': {
      value: function (){
        if(this.onTransitionStart) this.onTransitionStart(); 
        this.isExecuting = true;
        return this;
      }
    }
    ,'before': { 
      value: function (callback){
        this.onTransitionStart = callback;
        return this;
      }
    }
    // ,'config': {
    //   value: function (options){
    //     this.options.autoChangeState = options.autoChangeState || this.options.autoChangeState;
    //     return this;
    //   }
    // }
    ,'after': {
      value: function (callback){
        this.onTransitionEnd = callback;
        return this;
      }
    }
  });
  return Transition;
})();