:active pseudo-class doesn't work in mobile safari
In Webkit on iPhone/iPad/iPod, specifying styling for an :active pseudo-class for an <a> tag doesn't trigger when you tap on the element. How can I get this to trigger? Example code:
<style>
a:active {开发者_如何转开发
background-color: red;
}
</style>
<!-- snip -->
<a href="#">Click me</a>
<body ontouchstart="">
...
</body>
Applied just once, as opposed to every button element seemed to fix all buttons on the page. Alternatively you could use this small JS library called 'Fastclick'. It speed up click events on touch devices and takes care of this issue too.
As other answers have stated, iOS Safari doesn't trigger the :active pseudo-class unless a touch event is attached to the element, but so far this behaviour has been "magical". I came across this little blurb on the Safari Developer Library that explains it (emphasis mine):
You can also use the
-webkit-tap-highlight-colorCSS property in combination with setting a touch event to configure buttons to behave similar to the desktop. On iOS, mouse events are sent so quickly that the down or active state is never received. Therefore, the:activepseudo state is triggered only when there is a touch event set on the HTML element—for example, when ontouchstart is set on the element as follows:<button class="action" ontouchstart="" style="-webkit-tap-highlight-color: rgba(0,0,0,0);"> Testing Touch on iOS </button>Now when the button is tapped and held on iOS, the button changes to the specified color without the surrounding transparent gray color appearing.
In other words, setting an ontouchstart event (even if it's empty) is explicitly telling the browser to react to touch events.
In my opinion, this is flawed behaviour, and probably dates back to the time when the "mobile" web was basically nonexistent (take a look at those screenshots on the linked page to see what I mean), and everything was mouse oriented. It is interesting to note that other, newer mobile browsers, such as on Android, display `:active' pseudo-state on touch just fine, without any hacks like what is needed for iOS.
(Side-note: If you want to use your own custom styles on iOS, you can also disable the default grey translucent box that iOS uses in place of the :active pseudo-state by using the -webkit-tap-highlight-color CSS property, as explained in the same linked page above.)
After some experimentation, the expected solution of setting an ontouchstart event on the <body> element that all touch events then bubble to does not work fully. If the element is visible in the viewport when the page loads, then it works fine, but scrolling down and tapping an element that was out of the viewport does not trigger the :active pseudo-state like it should. So, instead of
<!DOCTYPE html>
<html><body ontouchstart></body></html>
attach the event to all elements instead of relying on the event bubbling up to the body (using jQuery):
$('body *').on('touchstart', function (){});
However, I am not aware of the performance implications of this, so beware.
EDIT: There is one serious flaw with this solution: even touching an element while scrolling the page will activate the :active pseudo state. The sensitivity is too strong. Android solves this by introducing a very small delay before the state is shown, which is cancelled if the page is scrolled. In light of this, I suggest using this only on select elements. In my case, I am developing a web-app for use out in the field which is basically a list of buttons to navigate pages and submit actions. Because the whole page is pretty much buttons in some cases, this won't work for me. You can, however, set the :hover pseudo-state to fill in for this instead. After disabling the default grey box, this works perfectly.
Add an event handler for ontouchstart in your <a> tag. This causes the CSS to magically work.
<a ontouchstart="">Click me</a>
This works for me:
document.addEventListener("touchstart", function() {},false);
Note: if you do this trick it is also worth removing the default tap–highlight colour Mobile Safari applies using the following CSS rule.
html {
-webkit-tap-highlight-color: rgba(0,0,0,0);
}
As of Dec 8, 2016, the accepted answer (<body ontouchstart="">...</body>) does not work for me on Safari 10 (iPhone 5s): That hack only works for those elements that were visible on page load.
However, adding:
<script type='application/javascript'>
document.addEventListener("touchstart", function() {}, false);
</script>
to the head does work the way I want, with the downside that now all touch events during scrolling also trigger the :active pseudo-state on the touched elements. (If this is a problem for you, you might consider FighterJet's :hover workaround.)
//hover for ios
-webkit-tap-highlight-color: #ccc;
This works for me, add to your CSS on the element that you want to highlight
Are you using all of the pseudo-classes or just the one? If you're using at least two, make sure they're in the right order or they all break:
a:link
a:visited
a:hover
a:active
..in that order. Also, If you're just using :active, add a:link, even if you're not styling it.
For those who don't want to use the ontouchstart, you can use this code
<script>
document.addEventListener("touchstart", function(){}, true);
</script>
I've published a tool that should solve this issue for you.
On the surface the problem looks simple, but in reality the touch & click behaviour needs to be customized quite extensively, including timeout functions and things like "what happens when you scroll a list of links" or "what happens when you press link and then move mouse/finger away from active area"
This should solve it all at once: https://www.npmjs.com/package/active-touch
You'll need to either have your :active styles assigned to .active class or choose your own class name. By default the script will work with all link elements, but you can overwrite it with your own array of selectors.
Honest, helpful feedback and contributions much appreciated!
I tried this answer and its variants, but none seemed to work reliably (and I dislike relying on 'magic' for stuff like this). So I did the following instead, which works perfectly on all platforms, not just Apple:
- Renamed css declarations that used
:activeto.active. Made a list of all the affected elements and added
pointerdown/mousedown/touchstartevent handlers to apply the.activeclass andpointerup/mouseup/touchendevent handlers to remove it. Using jQuery:let controlActivationEvents = window.PointerEvent ? "pointerdown" : "touchstart mousedown"; let controlDeactivationEvents = window.PointerEvent ? "pointerup pointerleave" : "touchend mouseup mouseleave"; let clickableThings = '<comma separated list of selectors>'; $(clickableThings).on(controlActivationEvents,function (e) { $(this).addClass('active'); }).on(controlDeactivationEvents, function (e) { $(this).removeClass('active'); });
This was a bit tedious, but now I have a solution that is less vulnerable to breakage between Apple OS versions. (And who needs something like this breaking?)
A solution is to rely on :target instead of :active:
<style>
a:target {
background-color: red;
}
</style>
<!-- snip -->
<a id="click-me" href="#click-me">Click me</a>
The style will be triggered when the anchor is targeted by the current url, which is robust even on mobile. The drawback is you need an other link to clear the anchor in the url. Complete example:
a:target {
background-color: red;
}<a id="click-me" href="#click-me">Click me</a>
<a id="clear" href="#">Clear</a>No 100% related to this question, but you can use css sibling hack to achieve this as well
HTML
<input tabindex="0" type="checkbox" id="145"/>
<label for="145"> info</label>
<span> sea</span>
SCSS
input {
&:checked + label {
background-color: red;
}
}
If you would like to use pure html/css tooltip
span {
display: none;
}
input {
&:checked ~ span {
display: block;
}
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title></title>
<style>
a{color: red;}
a:hover{color: blue;}
</style>
</head>
<body>
<div class="main" role="main">
<a href="#">Hover</a>
</div>
</body>
</html>
加载中,请稍侯......
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