jQuery scroll() detect when user stops scrolling
JavascriptJqueryScrollJquery EventsJavascript Problem Overview
Ok with this..
$(window).scroll(function()
{
$('.slides_layover').removeClass('showing_layover');
$('#slides_effect').show();
});
I can tell when someone is scrolling from what I understand. So with that I am trying to figure out how to catch when someone has stopped. From the above example you can see I am removing a class from a set of elements while the scrolling is occurring. However, I want to put that class back on when the user stops scrolling.
The reason for this is I am intent on having a layover show while the page is scrolling to give the page a special effect I am attempting to work on. But the one class I am trying to remove while scrolling conflicts with that effect as its a transparency effect to some nature.
Javascript Solutions
Solution 1 - Javascript
$(window).scroll(function() {
clearTimeout($.data(this, 'scrollTimer'));
$.data(this, 'scrollTimer', setTimeout(function() {
// do something
console.log("Haven't scrolled in 250ms!");
}, 250));
});
Update
I wrote an extension to enhance jQuery's default on
-event-handler. It attaches an event handler function for one or more events to the selected elements and calls the handler function if the event was not triggered for a given interval. This is useful if you want to fire a callback only after a delay, like the resize event, or such.
It is important to check the github-repo for updates!
https://github.com/yckart/jquery.unevent.js
;(function ($) {
var on = $.fn.on, timer;
$.fn.on = function () {
var args = Array.apply(null, arguments);
var last = args[args.length - 1];
if (isNaN(last) || (last === 1 && args.pop())) return on.apply(this, args);
var delay = args.pop();
var fn = args.pop();
args.push(function () {
var self = this, params = arguments;
clearTimeout(timer);
timer = setTimeout(function () {
fn.apply(self, params);
}, delay);
});
return on.apply(this, args);
};
}(this.jQuery || this.Zepto));
Use it like any other on
or bind
-event handler, except that you can pass an extra parameter as a last:
$(window).on('scroll', function(e) {
console.log(e.type + '-event was 250ms not triggered');
}, 250);
http://yckart.github.com/jquery.unevent.js/
(this demo uses resize
instead of scroll
, but who cares?!)
Solution 2 - Javascript
Using jQuery throttle / debounce
jQuery debounce is a nice one for problems like this. jsFidlle
$(window).scroll($.debounce( 250, true, function(){
$('#scrollMsg').html('SCROLLING!');
}));
$(window).scroll($.debounce( 250, function(){
$('#scrollMsg').html('DONE!');
}));
The second parameter is the "at_begin" flag. Here I've shown how to execute code both at "scroll start" and "scroll finish".
Using Lodash
As suggested by Barry P, jsFiddle, underscore or lodash also have a debounce, each with slightly different apis.
$(window).scroll(_.debounce(function(){
$('#scrollMsg').html('SCROLLING!');
}, 150, { 'leading': true, 'trailing': false }));
$(window).scroll(_.debounce(function(){
$('#scrollMsg').html('STOPPED!');
}, 150));
Solution 3 - Javascript
Rob W suggected I check out another post here on stack that was essentially a similar post to my original one. Which reading through that I found a link to a site:
http://james.padolsey.com/javascript/special-scroll-events-for-jquery/
This actually ended up helping solve my problem very nicely after a little tweaking for my own needs, but over all helped get a lot of the guff out of the way and saved me about 4 hours of figuring it out on my own.
Seeing as this post seems to have some merit, I figured I would come back and provide the code found originally on the link mentioned, just in case the author ever decided to go a different direction with the site and ended up taking down the link.
(function(){
var special = jQuery.event.special,
uid1 = 'D' + (+new Date()),
uid2 = 'D' + (+new Date() + 1);
special.scrollstart = {
setup: function() {
var timer,
handler = function(evt) {
var _self = this,
_args = arguments;
if (timer) {
clearTimeout(timer);
} else {
evt.type = 'scrollstart';
jQuery.event.handle.apply(_self, _args);
}
timer = setTimeout( function(){
timer = null;
}, special.scrollstop.latency);
};
jQuery(this).bind('scroll', handler).data(uid1, handler);
},
teardown: function(){
jQuery(this).unbind( 'scroll', jQuery(this).data(uid1) );
}
};
special.scrollstop = {
latency: 300,
setup: function() {
var timer,
handler = function(evt) {
var _self = this,
_args = arguments;
if (timer) {
clearTimeout(timer);
}
timer = setTimeout( function(){
timer = null;
evt.type = 'scrollstop';
jQuery.event.handle.apply(_self, _args);
}, special.scrollstop.latency);
};
jQuery(this).bind('scroll', handler).data(uid2, handler);
},
teardown: function() {
jQuery(this).unbind( 'scroll', jQuery(this).data(uid2) );
}
};
})();
Solution 4 - Javascript
I agreed with some of the comments above that listening for a timeout wasn't accurate enough as that will trigger when you stop moving the scroll bar for long enough instead of when you stop scrolling. I think a better solution is to listen for the user letting go of the mouse (mouseup) as soon as they start scrolling:
$(window).scroll(function(){
$('#scrollMsg').html('SCROLLING!');
var stopListener = $(window).mouseup(function(){ // listen to mouse up
$('#scrollMsg').html('STOPPED SCROLLING!');
stopListner(); // Stop listening to mouse up after heard for the first time
});
});
and an example of it working can be seen in this JSFiddle
Solution 5 - Javascript
ES6 style with checking scrolling start also.
function onScrollHandler(params: {
onStart: () => void,
onStop: () => void,
timeout: number
}) {
const {onStart, onStop, timeout = 200} = params
let timer = null
return (event) => {
if (timer) {
clearTimeout(timer)
} else {
onStart && onStart(event)
}
timer = setTimeout(() => {
timer = null
onStop && onStop(event)
}, timeout)
}
}
Usage:
yourScrollableElement.addEventListener('scroll', onScrollHandler({
onStart: (event) => {
console.log('Scrolling has started')
},
onStop: (event) => {
console.log('Scrolling has stopped')
},
timeout: 123 // Remove to use default value
}))
Solution 6 - Javascript
You could set an interval that runs every 500 ms or so, along the lines of the following:
var curOffset, oldOffset;
oldOffset = $(window).scrollTop();
var $el = $('.slides_layover'); // cache jquery ref
setInterval(function() {
curOffset = $(window).scrollTop();
if(curOffset != oldOffset) {
// they're scrolling, remove your class here if it exists
if($el.hasClass('showing_layover')) $el.removeClass('showing_layover');
} else {
// they've stopped, add the class if it doesn't exist
if(!$el.hasClass('showing_layover')) $el.addClass('showing_layover');
}
oldOffset = curOffset;
}, 500);
I haven't tested this code, but the principle should work.
Solution 7 - Javascript
function scrolled() {
//do by scroll start
$(this).off('scroll')[0].setTimeout(function(){
//do by scroll end
$(this).on('scroll',scrolled);
}, 500)
}
$(window).on('scroll',scrolled);
very small Version with start and end ability
Solution 8 - Javascript
This detects the scroll stop after 1 milisecond (or change it) using a global timer:
var scrollTimer;
$(window).on("scroll",function(){
clearTimeout(scrollTimer);
//Do what you want whilst scrolling
scrollTimer=setTimeout(function(){afterScroll()},1);
})
function afterScroll(){
//I catched scroll stop.
}
Solution 9 - Javascript
Ok this is something that I've used before.
Basically you look a hold a ref to the last scrollTop()
.
Once your timeout clears, you check the current scrollTop()
and if they are the same, you are done scrolling.
$(window).scroll((e) ->
clearTimeout(scrollTimer)
$('header').addClass('hidden')
scrollTimer = setTimeout((() ->
if $(this).scrollTop() is currentScrollTop
$('header').removeClass('hidden')
), animationDuration)
currentScrollTop = $(this).scrollTop()
)
Solution 10 - Javascript
please check the jquery mobile scrollstop event
$(document).on("scrollstop",function(){
alert("Stopped scrolling!");
});
Solution 11 - Javascript
For those Who Still Need This Here Is The Solution
$(function(){
var t;
document.addEventListener('scroll',function(e){
clearTimeout(t);
checkScroll();
});
function checkScroll(){
t = setTimeout(function(){
alert('Done Scrolling');
},500); /* You can increase or reduse timer */
}
});
Solution 12 - Javascript
This should work:
var Timer;
$('.Scroll_Table_Div').on("scroll",function()
{
// do somethings
clearTimeout(Timer);
Timer = setTimeout(function()
{
console.log('scrolling is stop');
},50);
});
Solution 13 - Javascript
Here is how you can handle this:
var scrollStop = function (callback) {
if (!callback || typeof callback !== 'function') return;
var isScrolling;
window.addEventListener('scroll', function (event) {
window.clearTimeout(isScrolling);
isScrolling = setTimeout(function() {
callback();
}, 66);
}, false);
};
scrollStop(function () {
console.log('Scrolling has stopped.');
});
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>.<br>
</body>
</html>