This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The transitionrun
event is fired when a CSS transition is first created, i.e. before any transition-delay
has begun.
Bubbles | Yes |
Cancelable | No |
Target objects |
document , element
|
Interface | TransitionEvent |
Property | Type | Description |
---|---|---|
target Read only
| EventTarget | The event target (the topmost target in the DOM tree). |
type Read only
| DOMString | The type of event. |
bubbles Read only
| Boolean | Whether the event normally bubbles or not |
cancelable Read only
| Boolean | Whether the event is cancellable or not? |
propertyName Read only
| DOMString | The name of the CSS property associated with the transition. |
elapsedTime Read only
| Float | The amount of time the transition has been running, in seconds, as of the time the event was generated. This value is not affected by the value of transition-delay . |
pseudoElement Read only
| DOMString | The name (beginning with two colons) of the CSS pseudo-element on which the transition occured (in which case the target of the event is that pseudo-element's corresponding element), or the empty string if the transition occurred on an element (which means the target of the event is that element). |
In the following example, we have a simple <div>
element, styled with a transition that includes a delay:
<div></div>
div { width: 200px; height: 200px; background: rgba(255,0,0,1); transition-property: transform background; transition-duration: 2s; transition-delay: 2s; } div:hover { transform: rotate(90deg); background: rgba(255,0,0,0); }
To this, we'll add some JavaScript to indicate where the transitionstart
and transitionrun
events fire.
var divElem = document.querySelector('div'); divElem.addEventListener('transitionrun', function() { console.log('transitionrun fired'); }); divElem.addEventListener('transitionstart', function() { console.log('transitionstart fired'); });
The difference is that:
transitionrun
fires when the transition is created (i.e. at the start of any delay).transitionstart
fires when the actual animation has begun (i.e. at the end of any delay).Specification | Status | Comment |
---|---|---|
CSS Transitions Level 2 The definition of 'transitionstart' in that specification. | Editor's Draft | Initial definition. |
We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!
Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|---|
Basic support | ? | No support | 53 (53) | No support | ? | ? |
Feature | Android | Edge | Firefox Mobile (Gecko) | IE Phone | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | ? | No support | 53.0 (53) | No support | ? | ? |
TransitionEvent
interfacetransitionstart
, transitionend
, transitioncancel
transition
, transition-delay
, transition-duration
, transition-property
, transition-timing-function
.
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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/Events/transitionrun