[javascript] CSS3 transition events

Are there any events fired by an element to check whether a css3 transition has started or end?

All modern browsers now support the unprefixed event:

element.addEventListener('transitionend', callback, false);

Works in the latest versions of Chrome, Firefox and Safari. Even IE10+.

If you simply want to detect only a single transition end, without using any JS framework here's a little convenient utility function:

function once = function(object,event,callback){
    var handle={};

    var eventNames=event.split(" ");

    var cbWrapper=function(){
        eventNames.forEach(function(e){
            object.removeEventListener(e,cbWrapper, false );
        });
        callback.apply(this,arguments);
    };

    eventNames.forEach(function(e){
        object.addEventListener(e,cbWrapper,false);
    });

    handle.cancel=function(){
        eventNames.forEach(function(e){
            object.removeEventListener(e,cbWrapper, false );
        });
    };

    return handle;
};

Usage:

var handler = once(document.querySelector('#myElement'), 'transitionend', function(){
   //do something
});

then if you wish to cancel at some point you can still do it with

handler.cancel();

It's good for other event usages as well :)

In Opera 12 when you bind using the plain JavaScript, 'oTransitionEnd' will work:

document.addEventListener("oTransitionEnd", function(){
    alert("Transition Ended");
});

however if you bind through jQuery, you need to use 'otransitionend'

$(document).bind("otransitionend", function(){
    alert("Transition Ended");
});

In case you are using Modernizr or bootstrap-transition.js you can simply do a change:

var transEndEventNames = {
    'WebkitTransition' : 'webkitTransitionEnd',
    'MozTransition'    : 'transitionend',
    'OTransition'      : 'oTransitionEnd otransitionend',
    'msTransition'     : 'MSTransitionEnd',
    'transition'       : 'transitionend'
},
transEndEventName = transEndEventNames[ Modernizr.prefixed('transition') ];

You can find some info here as well http://www.ianlunn.co.uk/blog/articles/opera-12-otransitionend-bugs-and-workarounds/

Just for fun, don't do this!

$.fn.transitiondone = function () {
  return this.each(function () {
    var $this = $(this);
    setTimeout(function () {
      $this.trigger('transitiondone');
    }, (parseFloat($this.css('transitionDelay')) + parseFloat($this.css('transitionDuration'))) * 1000);
  });
};


$('div').on('mousedown', function (e) {
  $(this).addClass('bounce').transitiondone();
});

$('div').on('transitiondone', function () {
  $(this).removeClass('bounce');
});

Update

All modern browsers now support the unprefixed event:

element.addEventListener('transitionend', callback, false);

https://caniuse.com/#feat=css-transitions

I was using the approach given by Pete, however I have now started using the following

$(".myClass").one('transitionend webkitTransitionEnd oTransitionEnd otransitionend MSTransitionEnd', 
function() {
 //do something
});

Alternatively if you use bootstrap then you can simply do

$(".myClass").one($.support.transition.end,
function() {
 //do something
});

This is becuase they include the following in bootstrap.js

+function ($) {
  'use strict';

  // CSS TRANSITION SUPPORT (Shoutout: http://www.modernizr.com/)
  // ============================================================

  function transitionEnd() {
    var el = document.createElement('bootstrap')

    var transEndEventNames = {
      'WebkitTransition' : 'webkitTransitionEnd',
      'MozTransition'    : 'transitionend',
      'OTransition'      : 'oTransitionEnd otransitionend',
      'transition'       : 'transitionend'
    }

    for (var name in transEndEventNames) {
      if (el.style[name] !== undefined) {
        return { end: transEndEventNames[name] }
      }
    }

    return false // explicit for ie8 (  ._.)
  }


  $(function () {
    $.support.transition = transitionEnd()
  })

}(jQuery);

Note they also include an emulateTransitionEnd function which may be needed to ensure a callback always occurs.

  // http://blog.alexmaccaw.com/css-transitions
  $.fn.emulateTransitionEnd = function (duration) {
    var called = false, $el = this
    $(this).one($.support.transition.end, function () { called = true })
    var callback = function () { if (!called) $($el).trigger($.support.transition.end) }
    setTimeout(callback, duration)
    return this
  }

Be aware that sometimes this event doesn’t fire, usually in the case when properties don’t change or a paint isn’t triggered. To ensure we always get a callback, let’s set a timeout that’ll trigger the event manually.

http://blog.alexmaccaw.com/css-transitions