css3 transition animation on load?

StackOverflow https://stackoverflow.com/questions/6805482

سؤال

Is it possible to use CSS3 transition animation on page load without using Javascript?

This is kind of what I want, but on page load:

http://rilwis.googlecode.com/svn/trunk/demo/image-slider.html

What I found so far

هل كانت مفيدة؟

المحلول

You can run a CSS animation on page load without using any JavaScript; you just have to use CSS3 Keyframes.

Let's Look at an Example...

Here's a demonstration of a navigation menu sliding into place using CSS3 only:

@keyframes slideInFromLeft {
  0% {
    transform: translateX(-100%);
  }
  100% {
    transform: translateX(0);
  }
}

header {  
  /* This section calls the slideInFromLeft animation we defined above */
  animation: 1s ease-out 0s 1 slideInFromLeft;
  
  background: #333;
  padding: 30px;
}

/* Added for aesthetics */ body {margin: 0;font-family: "Segoe UI", Arial, Helvetica, Sans Serif;} a {text-decoration: none; display: inline-block; margin-right: 10px; color:#fff;}
<header>
  <a href="#">Home</a>
  <a href="#">About</a>
  <a href="#">Products</a>
  <a href="#">Contact</a>
</header>

Break it down...

The important parts here are the keyframe animation which we call slideInFromLeft...

@keyframes slideInFromLeft {
    0% {
        transform: translateX(-100%);
    }
    100% {
        transform: translateX(0);
    }
}

...which basically says "at the start, the header will be off the left hand edge of the screen by its full width and at the end will be in place".

The second part is calling that slideInFromLeft animation:

animation: 1s ease-out 0s 1 slideInFromLeft;

Above is the shorthand version but here is the verbose version for clarity:

animation-duration: 1s; /* the duration of the animation */
animation-timing-function: ease-out; /* how the animation will behave */
animation-delay: 0s; /* how long to delay the animation from starting */
animation-iteration-count: 1; /* how many times the animation will play */
animation-name: slideInFromLeft; /* the name of the animation we defined above */

You can do all sorts of interesting things, like sliding in content, or drawing attention to areas.

Here's what W3C has to say.

نصائح أخرى

Very little Javascript is necessary:

window.onload = function() {
    document.body.className += " loaded";
}

Now the CSS:

.fadein {
    opacity: 0;
    -moz-transition: opacity 1.5s;
    -webkit-transition: opacity 1.5s;
    -o-transition: opacity 1.5s;
    transition: opacity 1.5s;
}

body.loaded .fadein {
    opacity: 1;
}

I know the question said "without Javascript", but I think it's worth pointing out that there is an easy solution involving one line of Javascript.

It could even be inline Javascript, something like that:

<body onload="document.body.className += ' loaded';" class="fadein">

That's all the JavaScript that's needed.

I think I have found a sort of work around for the OP question - instead of a transition beginning 'on.load' of the page - I found that using an animation for an opacity fade in had the same effect, (I was looking for the same thing as OP).

So I wanted to have the body text fade in from white(same as site background) to black text colour on page load - and I've only been coding since Monday so I was looking for an 'on.load' style thing code, but don't know JS yet - so here is my code that worked well for me. 

#main p {
  animation: fadein 2s;
}
@keyframes fadein {
  from { opacity: 0}
  to   { opacity: 1}
}

And for whatever reason, this doesn't work for .class only #id's(at least not on mine)

Hope this helps - as I know this site helps me a lot!

Well, this is a tricky one.

The answer is "not really".

CSS isn't a functional layer. It doesn't have any awareness of what happens or when. It's used simply to add a presentational layer to different "flags" (classes, ids, states).

By default, CSS/DOM does not provide any kind of "on load" state for CSS to use. If you wanted/were able to use JavaScript, you'd allocate a class to body or something to activate some CSS.

That being said, you can create a hack for that. I'll give an example here, but it may or may not be applicable to your situation.

We're operating on the assumption that "close" is "good enough":

<html>
<head>
<!-- Reference your CSS here... -->
</head>
<body>
    <!-- A whole bunch of HTML here... -->
    <div class="onLoad">OMG, I've loaded !</div>
</body>
</html>

Here's an excerpt of our CSS stylesheet:

.onLoad
{
    -webkit-animation:bounceIn 2s;
}

We're also on the assumption that modern browsers render progressively, so our last element will render last, and so this CSS will be activated last.

Similar to @Rolf's solution, but skip reference to external functions or playing with class. If opacity is to remain fixed to 1 once loaded, simply use inline script to directly change opacity via style. For example

<body class="fadein" onload="this.style.opacity=1">

where CSS sytle "fadein" is defined per @Rolf,defining transition and setting opacity to initial state (i.e. 0)

the only catch is that this does not work with SPAN or DIV elements, since they do not have working onload event

start it with hover of body than It will start when the mouse first moves on the screen, which is mostly within a second after arrival, the problem here is that it will reverse when out of the screen.

html:hover #animateelementid, body:hover #animateelementid {rotate ....}

thats the best thing I can think of: http://jsfiddle.net/faVLX/

fullscreen: http://jsfiddle.net/faVLX/embedded/result/

Edit see comments below:
This will not work on any touchscreen device because there is no hover, so the user won't see the content unless they tap it. – Rich Bradshaw

Ok I have managed to achieve an animation when the page loads using only css transitions (sort of!):

I have created 2 css style sheets: the first is how I want the html styled before the animation... and the second is how I want the page to look after the animation has been carried out.

I don't fully understand how I have accomplished this but it only works when the two css files (both in the head of my document) are separated by some javascript as follows.

I have tested this with Firefox, safari and opera. Sometimes the animation works, sometimes it skips straight to the second css file and sometimes the page appears to be loading but nothing is displayed (perhaps it is just me?)

<link media="screen,projection" type="text/css" href="first-css-file.css"  rel="stylesheet" />

<script language="javascript" type="text/javascript" src="../js/jQuery JavaScript Library v1.3.2.js"></script>

<script type='text/javascript'>
$(document).ready(function(){

// iOS Hover Event Class Fix
if((navigator.userAgent.match(/iPhone/i)) || (navigator.userAgent.match(/iPod/i)) ||
(navigator.userAgent.match(/iPad/i))) {
$(".container .menu-text").click(function(){  // Update class to point at the head of the list
});
}
});
</script>

<link media="screen,projection" type="text/css" href="second-css-file.css"  rel="stylesheet" />

Here is a link to my work-in-progress website: http://www.hankins-design.co.uk/beta2/test/index.html

Maybe I'm wrong but I thought browsers that do not support css transitions should not have any issues as they should skip straight to the second css file without delay or duration.

I am interested to know views on how search engine friendly this method is. With my black hat on I suppose I could fill a page with keywords and apply a 9999s delay on its opacity.

I would be interested to know how search engines deal with the transition-delay attribute and whether, using the method above, they would even see the links and information on the page.

More importantly I would really like to know why this is not consistent each time the page loads and how I can rectify this!

I hope this can generate some views and opinions if nothing else!

If anyone else had problems doing two transitions at once, here's what I did. I needed text to come from top to bottom on page load.

HTML 

<body class="existing-class-name" onload="document.body.classList.add('loaded')">

HTML 

<div class="image-wrapper">
    <img src="db-image.jpg" alt="db-image-name">
    <span class="text-over-image">DB text</span>
</div>

CSS 

.text-over-image {
    position: absolute;
    background-color: rgba(110, 186, 115, 0.8);
    color: #eee;
    left: 0;
    width: 100%;
    padding: 10px;
    opacity: 0;
    bottom: 100%;
    -webkit-transition: opacity 2s, bottom 2s;
    -moz-transition: opacity 2s, bottom 2s;
    -o-transition: opacity 2s, bottom 2s;
    transition: opacity 2s, bottom 2s;
}

body.loaded .text-over-image {
    bottom: 0;
    opacity: 1;
}

Don't know why I kept trying to use 2 transition declarations in 1 selector and (not really) thinking it would use both.

CSS only with a delay of 3s

a few points to take here:

  • multiple animations in one call
  • we create a wait animation that just delays the actual one (the second one in our case).

Code:

header {
    animation: 3s ease-out 0s 1 wait, 0.21s ease-out 3s 1 slideInFromBottom;
}

@keyframes wait {
    from { transform: translateY(20px); }
    to { transform: translateY(20px); }
}

@keyframes slideInFromBottom {
  from { transform: translateY(20px); opacity: 0; }
  to { transform: translateY(0); opacity: 1; }
}

Not really, as CSS is applied as soon as possible, but the elements might not be drawn yet. You could guess a delay of 1 or 2 seconds, but this won't look right for most people, depending on the speed of their internet.

In addition, if you want to fade something in for instance, it would require CSS that hides the content to be delivered. If the user doesn't have CSS3 transitions then they would never see it.

I'd recommend using jQuery (for ease of use + you may wish to add animation for other UAs) and some JS like this: 

$(document).ready(function() {
    $('#id_to_fade_in')
        .css({"opacity":0})   // Set to 0 as soon as possible – may result in flicker, but it's not hidden for users with no JS (Googlebot for instance!)
        .delay(200)           // Wait for a bit so the user notices it fade in
        .css({"opacity":1});  // Fade it back in. Swap css for animate in legacy browsers if required.
});

Along with the transitions added in the CSS. This has the advantage of easily allowing the use of animate instead of the second CSS in legacy browsers if required.

مرخصة بموجب: CC-BY-SA مع الإسناد
لا تنتمي إلى StackOverflow
scroll top