Fluidly stop a CSS3 Animation halted mid-animation? [duplicate] - html

This question already has answers here:
css3 animation on :hover; force entire animation
(7 answers)
Closed 8 years ago.
I'm running into a small problem attempting to have an animation stopped mid-animation gracefully returning to the default state. I'm applying an animation to a child element using the :hover pseudoclass on a parent element, but would like the animation to gracefully return to the default state when I stop hovering on the element. I'm getting the feeling that I shouldn't be using the :hover pseudoclass here and there's another method of approaching it, but I can't seem to figure out how to get it to transition off. It just instantly reverts to the base state, which of course makes sense because the animation is being stripped - but that's not the desired effect. This is the current HTML:
<div id="el1">
<div class="child"></div>
</div>
and the current CSS
#el1 {
margin-top: 100px;
position: relative;
background: transparent url(./image.png) no-repeat;
height: 100px;
width: 100px;
}
#el1 .child {
height: 100%;
width: 100%;
background-color: white;
opacity: 0;
}
#el1:hover .child {
-webkit-animation-name: semiopacity;
-webkit-animation-iteration-count: infinite;
-webkit-animation-duration: 0.5s;
-webkit-animation-direction: alternate;
-webkit-animation-timing-function: linear;
-webkit-animation-fill-mode: forwards;
}
#-webkit-keyframes semiopacity {
from { opacity: 0; }
to { opacity: 0.4; }
}
To recap: There's a flashing white effect over the image when hovering. I want it to animate back to the original keyframe when I stop hovering instead of snapping back to "off". I can change either the HTML or CSS; no restrictions on how to make it work.

css3 animation on :hover; force entire animation
Something similar asked a couple days ago. This person also wanted their entire animation to show after hover was removed. Check it out.

Related

How does the #keyframes example know what information of how to generate the square?

div {
width: 100px;
height: 100px;
background-color: red;
animation-name: example;
animation-duration: 4s;
}
#keyframes example {
from {background-color: red;}
to {background-color: yellow;}
}
</style>
When put into a standard .html file layout it creates a 100x100 color-changing square. I'm confused, how is "#keyframes example" is getting the animation information from Div? I think the div becomes used by #keyframes to generate the square.
The CSS #keyframes syntax is a way to define generic stepped animations by providing a start and end point, and the browser smoothly animates from your starting value(s) to your ending value(s). Keyframe animations can be applied to HTML elements using the animation-name property. animation-duration defines how long the animation should take to run from start to end.
In your example, all <div> elements in the document will have the example animation applied to them because you applied it with the animation-name property:
animation-name: example;
After the animation is complete, the animated element(s) will revert back to their original state by default. If you're looking to preserve the ending state of the animation after it's complete, you can accomplish this with the animation-fill-mode property.

Transition to default class upon removal of CSS class with animation

I am animating a button. A class is assigned depending on my app state. This is actually implemented in Svelte as follows:
<div class="default"
class:run-animation="{$animate === true}">
But the equivalent in vanilla javascript without Svelte is:
let element = document... (find element)
element.classList.add("run-animation")
... later ...
element.classList.remove("run-animation)
For the sake of a minimum reproducible example, the classes I'm trying to animate/transition between look like this:
.default {
top: 20px;
color: white;
}
#keyframes button-animation {
from {
top: 20px;
color: white;
}
20% {
top: 23px;
color: white;
}
25% {
color: red;
}
100% {
top: 23px;
color: red;
}
}
.run-animation {
animation-name: button-animation;
animation-duration: 2s;
/* Preserve the effect of the animation at ending */
animation-fill-mode: forwards;
}
I add the class to the element, and the button animates just like I want it to. My problem arises when I remove the class. I want the button to transition smoothly back to the default CSS. I have tried adding the animation to the run-animate class:
.run-animation {
animation-name: ... ;
top: 23px;
color: red;
}
I have come across many people stating the transition upon class removal will apply if I add a transition property to the default class. I have tried this as follows:
.default {
...
transition: all 3s linear;
}
But it isn't working. The animation runs smoothly when it is added but the styling immediately reverts to the default when the class is removed (no smooth transition).
MY GOAL: I want to smoothly transition away from the end-state of the animation to the default class when the animate class is removed. Is this possible?
Ideally, I'm adding the class with the Svelte logic at the top so the animation should not be triggered in javascript but rather naturally occur as a result of class assignment.
(My code in practice is a little more complicated than shown, the button has another class with styles not being animated at all and the animation includes more styles such as box-shadow and text-shadow. Still, I don't see why this should be more problematic than just color and top included above)
// JS only toggles '.animation'
document.querySelector("button").addEventListener("click", () => {
document.querySelector("div.default").classList.toggle("animation");
});
body {display: flex}
button {position: absolute; left: 120px}
div.default {
position: absolute;
width: 100px;
height: 100px;
background: darkgreen;
}
/* Above code to make a visible working example */
div.default {
top: 20px;
color: white;
transition: top 0.4s, color 0.1s 0.4s;
}
#keyframes define-animation {
from {
top: 20px;
color: white;
}
}
div.default.animation {
animation-name: define-animation;
animation-duration: 2s;
top: 24px;
color: red;
}
<div class="default">I'm colourful</div>
<button>Toggle ".animation"-class</button>
Above is a working snippet with an animation running on class addition and no reverse transition on class removal. I have tried setting animation direction to opposite values in .default and .animation. I have tried defining the .animate end state properties in the class and/or in the keyframes to attributes.
EDIT: It works now! How?
You cannot apply:
animation-fill-mode: forwards;
The end-attributes need to be defined in the animate class not in the keyframe.
The animation plays when the class is added. Transition timings are used when the class is removed (if the animation has completed).
To get a transition effect, you can use the transition-property.
The transition-property can be used here, since every property you want to animate only has a start- and end-value.
Translating animation-percentages to seconds
To translate the percentages of your CSS Animation button-animation to seconds, you just calculate 'percentage' * 'animation-duration'.
This works for both the transition-duration-property as well as for the transition-delay-property.
Example:
color is being animated from 20% to 25%, which is a duration of 5% with a delay of 20%.
All in all, the animation should take 2 seconds.
So we calculate for:
transition-duration: 5% * 2s = 0.1s
transition-delay: 20% * 2s = 0.4s
With that, we can add transition: color 0.1s 0.4s to the .default-class.
Why add it to .default, and not to .animation?
If we were to add the transition-property to .animation, the following would happen:
When adding .animation, there will be a transition-effect, since the element now has a transition-property defined.
But when removing .animation, the element would no longer have a transition-property defined, meaning there would be no transition.
Now, we want to transition on both adding and removing .animation, meaning we want to have a transition-property defined both when .animation is present and when it is not. That means, transition should not be defined in .animation.
// JS only toggles '.animation'
document.querySelector("button").addEventListener("click", () => {
document.querySelector("div.default").classList.toggle("animation");
});
body {display: flex}
button {align-self: center}
div.default {
position: relative;
border: 2px solid black;
width: 100px;
height: 100px;
background: darkgreen;
}
/* Above code to make a visible working example */
div.default {
top: 20px;
color: white;
transition: top 0.4s, color 0.1s 0.4s;
}
div.default.animation {
top: 23px;
color: red;
}
<div class="default">Some text to see the "color"-property</div>
<button>Toggle ".animation"-class</button>
Why does it behave differently...
...when placing the properties inside the to-section of the animation, than when placing them inside .animation itself?
That is, because the properties are not directly applied to the element itself, but rather the element is stopped in its animation (right at the very end), giving only the appearance of the properties being actually applied.
Removing animation-fill-mode: forwards shows the actually applied properties after the animation has played. Those actually applied properties will be the start-values for transition after .animation is removed.
When defining these properties in .animation, they will inherently be the to-values for the animation (if not defined otherwise in animation itself), and be the applied properties of the element.
That means, when removing .animation, the transition will start from there.

How can I reverse an animation after hover like a transition?

CSS transitions animate back to the previous state, following the transition rules in reverse. But animations don't. They just go back to the original state abruptly (eg., when :hover or the class is removed). Is there a way to make animations behave like transitions (like the code below).
.box {
width: 50px;
height: 50px;
}
.box.transition {
background-color: green;
transition: 500ms linear all;
}
.box.transition:hover {
width: 100px;
height: 100px;
}
.box.animation {
background-color: red;
animation-duration: 500ms;
animation-fill-mode: both;
animation-timing-function: linear;
}
.box.animation:hover {
animation-name: zoom;
}
#keyframes zoom {
to {
width: 100px;
height: 100px;
}
}
<!-- If I "unhover" .box.animation, it goes back to the original state abruptly -->
<div class="box transition"></div>
<div class="box animation"></div>
Animation like transitions
Yes and no you can make them behave similarly but not identical, but not with :hover.
The hover state ends when you stop hovering an element. So when you stop hovering it, the css rule that targets :hover will instantly be removed.
Transition define what to do when there are changes to different states.
Animation go from one state to another defined by an animation.
Setting the animation direction will make it look closer to a transition.
animation-direction: alternate; will loop over an animation from start to finish and backagain.

Change slowly z-index value after hover has ended on image

I have blog post with set of images that are enlarged on hover. My problem is that when i enlarge element and it overlaps with other image that is later in page render order then the next image is on top of the enlarged one.
The easy way to stop this is to give some kind of z-index on :hover pseudo selector. But then i have very pesky problem when just after I stop hovering my image then next one is on top of it for fraction of second.
You can see behaviour in this imgur album or on jsfiddle(hover first image)
In short i have following css for hovering effect:
.photo-exp
{
position: relative;
transition: all .4s ease-in-out;
/* some properties deleted which have no connection to hovering effect */
}
.photo-exp:hover
{
transform: scale(1.7);
z-index : 10;
}
It would be very easy to have same effect with javascript and setTimeout function.
But i would like to avoid javascript solution and have some CSS workaround which will change slowly z-index in time after hovering ends.
I tried CSS transition but it is not working
I tried to eddit this snippet but i could not get it working in the way that i wanted.
You need to assign a new transition-delay property, and remove it as soon as the hover begins. That way the z-index can persist for some time even after the mouse is gone. It's a little counter-intuitive; I would expect that the delay should be added on hover and removed off-hover but the opposite works on chrome:
.expander {
position: absolute;
left: 50%; top: 50%;
width: 100px; height: 100px;
margin-top: -50px; margin-left: -50px;
z-index: 1;
transition: transform 400ms 0ms, z-index 0ms 400ms; /* That final "400ms" delays the z-index transition! */
}
.expander:hover {
transform: scale(1.8);
z-index: 2; /* A hovered expander is always on top */
transition: transform 400ms 0ms, z-index 0ms 0ms; /* Remove the z-index transition delay on hover. This is counter-intuitive but works. */
}
.expander:nth-child(1) {
margin-left: -105px;
background-color: #a00000;
}
.expander:nth-child(2) {
margin-left: 5px;
background-color: #00af00;
}
<div class="expander"></div>
<div class="expander"></div>
Note that (unless you try to mouse around really quickly in order to break it) neither square bleeds through the other, not even for a frame, when they expand.
I've also finally managed to solve by myself my problem.
It's more intuitive than #Gershom Maes answer in my opinion.
Fiddle
I have used animation system to achieve the result.
#keyframes nohovering {
0% { z-index: 9; }
100% { z-index: 1; }
}
#keyframes hovering {
0% { z-index: 10; }
100% { z-index: 10; }
}
First one will be by default fired on selector without :hover like this
animation: nohovering 0.9s;
It will guarantee that after i complete my hovering it will go smoothly down from z-index 9 to z-index 1. After hovering my image will be on top of other images. When i tested it for z-index 10 for 0% i had a little glitch when i tried to hovered 2 images at same time and then hover only 1 of them.
For my hovering selector I used:
animation: hovering 0.1s infinite;
It will just loop my image on z-index 10. On hover it will always be on top of the other images. Short animation time guarantee that it will go off after hovering stopped in maximum time of 0.1s.
After deleting normal static z-indexes it works.

Create Background Color CSS3 Animations after Background Image Animation

I am trying to create background-color CSS3 Keyframe animations after the first animation which is a background image. I am not able to create another animation after the text animation fades. After the text animation fades, I would like the background's opacity to turn to 0.3 and once again fade in text. Below is what I have.
Please see full code here: codepen:https://codepen.io/imdaone/pen/JJrYyV
.background {
width: 80%;
height: 220px;
margin: auto;
background: url(imgs/ad-ex.png) no-repeat top left;
background-size: 100%;
animation: move 5s 1 linear;
animation-iteration-count: 1;
animation-fill-mode: forwards;
}
Looks like you are trying to attempt to do animations with sequences. If I am not wrong, you cannot do it with pure css. You might want to venture into using some javascript animation library where it can handle sequencial animation.
You can still use vanilla js but i think its more tedious just to achieve what you want