CSS animation-fill-mode
We're always super excited to get into CSS animations because, quite frankly, they're incredibly awesome. One overlooked animation property, however, is the animation-fill-mode property. This CSS property sets the state of the end animation when the animation is not running. Here's a quick example:
@keyframes fadeIn{
0% { opacity: 0 }
100% { opacity: 1 }
}
.fadeIn {
animation-name: fadeIn;
animation-duration: 1s;
animation-fill-mode: forwards;
}
In the case of my fadeIn animation, I want the element to stay at an opacity of 1 when the animation is complete. If I don't set the value to forwards, the element would go back to an opacity of 0 after the animation runs. In most cases, you'll likely want the the value of animation-fill-mode to be forwards, so don't forget to add it!
![Write Better JavaScript with Promises]()
You've probably heard the talk around the water cooler about how promises are the future. All of the cool kids are using them, but you don't see what makes them so special. Can't you just use a callback? What's the big deal? In this article, we'll...
![Designing for Simplicity]()
Before we get started, it's worth me spending a brief moment introducing myself to you. My name is Mark (or @integralist if Twitter happens to be your communication tool of choice) and I currently work for BBC News in London England as a principal engineer/tech...
![Add Site Screenshots for External Links Using MooTools Tooltips]()
Before you send your user to an unknown external website, why not provide them a screenshot of the site via a tooltip so they may preview the upcoming page? Here's how you can do just that using MooTools.
The MooTools JavaScript
The first step is to grab...
![Spatial Navigation]()
Spatial navigation is the ability to navigate to focusable elements based on their position in a given space. Spatial navigation is a must when your site or app must respond to arrow keys, a perfect example being a television with directional pad remote. Firefox OS TV apps are simply...
Indeed, animation-fill-mode defaults to “none”, which means no animation style is applied when the animation starts or ends. You could expect “forwards” to be the default one, but… nope.
The other values are “backwards” and “both”. Cue to MDN page:
https://developer.mozilla.org/en-US/docs/Web/CSS/animation-fill-mode
> You could expect “forwards” to be the default one, but… nope.
This is why Max: http://www.w3.org/TR/css3-animations/
> The keyframes specify the behavior of one cycle of the animation… If a 0% or “from” keyframe is not specified, then the user agent constructs a 0% keyframe using the computed values of the properties being animated. If a 100% or “to” keyframe is not specified, then the user agent constructs a 100% keyframe using the computed values of the properties being animated.
> …by default an animation does not affect property values after the animation ends. The ‘animation-fill-mode’ property can override this behavior.
So, it is assumed that the non-animated state is the ‘default’ resting state for the animation.
This definitely helped me out a few times. I also like the “animation-direction” property, it can lead to interesting effects: http://cdpn.io/Kdslg