How do I re-trigger a WebKit CSS animation via Jav

Question

So, I've got this -webkit-animation rule:

@-webkit-keyframes shake {
    0% {
        left: 0;
    }
    25% {
        left: 12px;
    }
    50% {
        left: 0;
    }
    75% {
        left: -12px;
    }
    100% {
        left:0;
    }
}

And some CSS defining some of the animation rules on my box:

#box{
    -webkit-animation-duration: .02s;
    -webkit-animation-iteration-count: 10;
    -webkit-animation-timing-function: linear;
}

I can shake the #box like this:

document.getElementById("box").style.webkitAnimationName = "shake";

But I can't shake it again later.

This only shakes the box once:

someElem.onclick = function(){
    document.getElementById("box").style.webkitAnimationName = "shake";
}

How can I re-trigger a CSS animation via JavaScript without using timeouts or multiple animations?

Answer 1

Clone works pretty good on paused Karaoke: On IE11 had to force a reflow (R. Krupiński's shorter version).

$('#lyrics').text("Why does it hurt when I pee?");
changeLyrics('3s');  

function changeLyrics(sec) {
  str = 'lyrics '+ sec + ' linear 1';
  $('#lyrics').css( 'animation', str);
  $('#lyrics').css( 'animation-play-state', 'running' );
  $('#lyrics').replaceWith($('#lyrics').clone(true)); 
}

or you can use the following:

function resetAnimation(elm) {
  $('#'+elm).replaceWith($('#'+elm).clone(true)); 
}

Answer 2

Is there an issue with using setTimeout() to remove the class and then read it 5ms later?

svg.classList.remove('animate');
setTimeout(function() {
  svg.classList.add('animate');
}, 10);

Answer 3

Following the suggestion from https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Animations/Tips, remove and then add the animation class, using requestAnimationFrame to ensure that the rendering engine processes both changes. I think this is cleaner than using setTimeout, and handles replaying an animation before the previous play has completed.

$('#shake-the-box').click(function(){   
  $('#box').removeClass("trigger");
  window.requestAnimationFrame(function(time) {
  window.requestAnimationFrame(function(time) {
      $('#box').addClass("trigger");
    });
    });    

});

http://jsfiddle.net/gcmwyr14/5/

Answer 4

Reset the value first. Use reflow to apply the change without using timeout:

function shake() {
  var box = document.getElementById("box");
  box.style.animationName = null;
  box.offsetHeight; /* trigger reflow */
  box.style.animationName = "shake";
}

@keyframes shake {
    0% { left: 0; }
   25% { left: 12px; }
   50% { left: 0; }
   75% { left: -12px; }
  100% { left: 0; }
}

#box {
    position: absolute;
    width: 75px; height: 75px;
    background-color: black;
    animation-duration: .02s;
    animation-iteration-count: 10;
    animation-timing-function: linear;
}

button {
    position: absolute;
    top: 100px;
}

<div id="box"></div>
<button onclick="shake()">Shake</button>

In contrast to the accepted answer that recommends animationEnd, this method resets the animation even when it's still in progress. This might be or might be not what you want.

---

An alternative would be to create a duplicate @keyframes animation and switch between the two:

function shake() {
  var box = document.getElementById("box");
  if (box.style.animationName === "shake")
      box.style.animationName = "shake2";
  else
      box.style.animationName = "shake";
}

@keyframes shake {
    0% { left: 0; }
   25% { left: 12px; }
   50% { left: 0; }
   75% { left: -12px; }
  100% { left: 0; }
}

@keyframes shake2 {
    0% { left: 0; }
   25% { left: 12px; }
   50% { left: 0; }
   75% { left: -12px; }
  100% { left: 0; }
}

#box {
    position: absolute;
    width: 75px; height: 75px;
    background-color: black;
    animation-duration: .02s;
    animation-iteration-count: 10;
    animation-timing-function: linear;
}

button {
    position: absolute;
    top: 100px;
}

<div id="box"></div>
<button onclick="shake()">Shake</button>

Answer 5

You have to first remove the animation, then add it again. Eg:

document.getElementById("box").style.webkitAnimationName = "";
setTimeout(function ()
{
    document.getElementById("box").style.webkitAnimationName = "shake";
}, 0);

To do this without setTimeout remove the animation during onmousedown, and add it during onclick:

someElem.onmousedown = function()
{
    document.getElementById("box").style.webkitAnimationName = "";
}
someElem.onclick = function()
{
    document.getElementById("box").style.webkitAnimationName = "shake";
}

Answer 6

A simple but effective alternative:

HTML:

<div id="box"></div>
<button id="shake-the-box">Shake it!</button>​

css:

#box{
    background: blue;
    margin:30px;
    height:50px;
    width:50px;
    position:relative;
    -moz-animation:shake .2s 0 linear 1; 
    -webkit-animation:shake .2s 0 linear 1; 
}
#box.trigger{
    display:table;
}
@-webkit-keyframes shake {
    0% {
        left: 0;
    }
    25% {
        left: 12px;
    }
    50% {
        left: 0;
    }
    75% {
        left: -12px;
    }
    100% {
        left:0;
    }
}
@-moz-keyframes shake {
    0% {
        left: 0;
    }
    25% {
        left: 12px;
    }
    50% {
        left: 0;
    }
    75% {
        left: -12px;
    }
    100% {
        left:0;
    }
}​

jQuery:

$('#shake-the-box').click(function(){

  $('#box').toggleClass('trigger');

});​

Demo:
http://jsfiddle.net/5832R/2/

Issues:
I don't know if it works on Firefox, because the animation doesn't seem to work there...