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Method runs multiple times [duplicate]

I want to trigger an ajax request when the user has finished typing in a text box. I don't want it to run the function on every time the user types a letter because that would result in A LOT of ajax requests, however I don't want them to have to hit the enter button either.
Is there a way so I can detect when the user has finished typing and then do the ajax request?
Using jQuery here!

So, I'm going to guess finish typing means you just stop for a while, say 5 seconds. So with that in mind, let's start a timer when the user releases a key and clear it when they press one. I decided the input in question will be #myInput.
Making a few assumptions...
//setup before functions
var typingTimer; //timer identifier
var doneTypingInterval = 5000; //time in ms, 5 seconds for example
var $input = $('#myInput');
//on keyup, start the countdown
$input.on('keyup', function () {
clearTimeout(typingTimer);
typingTimer = setTimeout(doneTyping, doneTypingInterval);
});
//on keydown, clear the countdown
$input.on('keydown', function () {
clearTimeout(typingTimer);
});
//user is "finished typing," do something
function doneTyping () {
//do something
}

The chosen answer above does not work.
Because typingTimer is occassionaly set multiple times (keyup pressed twice before keydown is triggered for fast typers etc.) then it doesn't clear properly.
The solution below solves this problem and will call X seconds after finished as the OP requested. It also no longer requires the redundant keydown function. I have also added a check so that your function call won't happen if your input is empty.
//setup before functions
var typingTimer; //timer identifier
var doneTypingInterval = 5000; //time in ms (5 seconds)
//on keyup, start the countdown
$('#myInput').keyup(function(){
clearTimeout(typingTimer);
if ($('#myInput').val()) {
typingTimer = setTimeout(doneTyping, doneTypingInterval);
}
});
//user is "finished typing," do something
function doneTyping () {
//do something
}
And the same code in vanilla JavaScript solution:
//setup before functions
let typingTimer; //timer identifier
let doneTypingInterval = 5000; //time in ms (5 seconds)
let myInput = document.getElementById('myInput');
//on keyup, start the countdown
myInput.addEventListener('keyup', () => {
clearTimeout(typingTimer);
if (myInput.value) {
typingTimer = setTimeout(doneTyping, doneTypingInterval);
}
});
//user is "finished typing," do something
function doneTyping () {
//do something
}
This solution does use ES6 but it's not necessary here. Just replace let with var and the arrow function with a regular function.

It's just one line with underscore.js debounce function:
$('#my-input-box').keyup(_.debounce(doSomething , 500));
This basically says doSomething 500 milliseconds after I stop typing.
For more info: http://underscorejs.org/#debounce

Late answer but I'm adding it because it's 2019 and this is entirely achievable using pretty ES6, no third party libraries, and I find most of the highly rated answers are bulky and weighed down with too many variables.
Elegant solution taken from this excellent blog post.
function debounce(callback, wait) {
let timeout;
return (...args) => {
clearTimeout(timeout);
timeout = setTimeout(function () { callback.apply(this, args); }, wait);
};
}
window.addEventListener('keyup', debounce( () => {
// code you would like to run 1000ms after the keyup event has stopped firing
// further keyup events reset the timer, as expected
}, 1000))

Yes, you can set a timeout of say 2 seconds on each and every key up event which will fire an ajax request. You can also store the XHR method and abort it on subsequent key press events so that you save bandwith even more. Here's something I've written for an autocomplete script of mine.
var timer;
var x;
$(".some-input").keyup(function () {
if (x) { x.abort() } // If there is an existing XHR, abort it.
clearTimeout(timer); // Clear the timer so we don't end up with dupes.
timer = setTimeout(function() { // assign timer a new timeout
x = $.getJSON(...); // run ajax request and store in x variable (so we can cancel)
}, 2000); // 2000ms delay, tweak for faster/slower
});
Hope this helps,
Marko

var timer;
var timeout = 1000;
$('#in').keyup(function(){
clearTimeout(timer);
if ($('#in').val) {
timer = setTimeout(function(){
//do stuff here e.g ajax call etc....
var v = $("#in").val();
$("#out").html(v);
}, timeout);
}
});
full example here: http://jsfiddle.net/ZYXp4/8/

Both top 2 answers doesn't work for me. So, here is my solution:
var timeout = null;
$('#myInput').keyup(function() {
clearTimeout(timeout);
timeout = setTimeout(function() {
//do stuff here
}, 500);
});

Declare the following delay function:
var delay = (function () {
var timer = 0;
return function (callback, ms) {
clearTimeout(timer);
timer = setTimeout(callback, ms);
};
})()
and then use it:
let $filter = $('#item-filter');
$filter.on('keydown', function () {
delay(function () {
console.log('this will hit, once user has not typed for 1 second');
}, 1000);
});

Modifying the accepted answer to handle additional cases such as paste:
//setup before functions
var typingTimer; //timer identifier
var doneTypingInterval = 2000; //time in ms, 2 second for example
var $input = $('#myInput');
// updated events
$input.on('input propertychange paste', function () {
clearTimeout(typingTimer);
typingTimer = setTimeout(doneTyping, doneTypingInterval);
});
//user is "finished typing," do something
function doneTyping () {
//do something
}

I like Surreal Dream's answer but I found that my "doneTyping" function would fire for every keypress, i.e. if you type "Hello" really quickly; instead of firing just once when you stop typing, the function would fire 5 times.
The problem was that the javascript setTimeout function doesn't appear to overwrite or kill the any old timeouts that have been set, but if you do it yourself it works! So I just added a clearTimeout call just before the setTimeout if the typingTimer is set. See below:
//setup before functions
var typingTimer; //timer identifier
var doneTypingInterval = 5000; //time in ms, 5 second for example
//on keyup, start the countdown
$('#myInput').on("keyup", function(){
if (typingTimer) clearTimeout(typingTimer); // Clear if already set
typingTimer = setTimeout(doneTyping, doneTypingInterval);
});
//on keydown, clear the countdown
$('#myInput').on("keydown", function(){
clearTimeout(typingTimer);
});
//user is "finished typing," do something
function doneTyping () {
//do something
}
N.B. I would have liked to have just added this as a comment to Surreal Dream's answer but I'm a new user and don't have enough reputation. Sorry!

I don't think keyDown event is necessary in this case (please tell me why if I'm wrong). In my (non-jquery) script similar solution looks like that:
var _timer, _timeOut = 2000;
function _onKeyUp(e) {
clearTimeout(_timer);
if (e.keyCode == 13) { // close on ENTER key
_onCloseClick();
} else { // send xhr requests
_timer = window.setTimeout(function() {
_onInputChange();
}, _timeOut)
}
}
It's my first reply on Stack Overflow, so I hope this helps someone, someday:)

const inText = document.getElementById('inText')
const outText = document.getElementById('outText')
const delay = 1000
let timer
inText.addEventListener('input', code => {
clearTimeout(timer);
timer = setTimeout(x => {
outText.innerHTML = inText.value
}, delay, code)
})
<textarea id='inText'>edit this and...</textarea>
<pre id='outText'>see the results after you stop typing for one second</pre>

Well, strictly speaking no, as the computer cannot guess when the user has finished typing. You could of course fire a timer on key up, and reset it on every subsequent key up. If the timer expires, the user hasn't typed for the timer duration - you could call that "finished typing".
If you expect users to make pauses while typing, there's no way to know when they are done.
(Unless of course you can tell from the data when they are done)

agree with the #going 's answer. Another similar solution that worked for me is the one below. The only difference is that I am using .on("input"...) instead of keyup. This only captures changes in the input. other keys like Ctrl, Shift etc. are ignored
var typingTimer; //timer identifier
var doneTypingInterval = 5000; //time in ms (5 seconds)
//on input change, start the countdown
$('#myInput').on("input", function() {
clearTimeout(typingTimer);
typingTimer = setTimeout(function(){
// doSomething...
}, doneTypingInterval);
});

I was implementing the search at my listing and needed it to be ajax based. That means that on every key change, searched results should be updated and displayed. This results in so many ajax calls sent to server, which is not a good thing.
After some working, I made an approach to ping the server when the user stops typing.
This solution worked for me:
$(document).ready(function() {
$('#yourtextfield').keyup(function() {
s = $('#yourtextfield').val();
setTimeout(function() {
if($('#yourtextfield').val() == s){ // Check the value searched is the latest one or not. This will help in making the ajax call work when client stops writing.
$.ajax({
type: "POST",
url: "yoururl",
data: 'search=' + s,
cache: false,
beforeSend: function() {
// loading image
},
success: function(data) {
// Your response will come here
}
})
}
}, 1000); // 1 sec delay to check.
}); // End of keyup function
}); // End of document.ready
You will notice that there is no need to use any timer while implementing this.

I feel like the solution is somewhat a bit simpler with the input event:
var typingTimer;
var doneTypingInterval = 500;
$("#myInput").on("input", function () {
window.clearTimeout(typingTimer);
typingTimer = window.setTimeout(doneTyping, doneTypingInterval);
});
function doneTyping () {
// code here
}

I just figured out a simple code to wait for user to finish typing:
step 1.set time out to null then clear the current timeout when the user is typing.
step 2.trigger clear timeout to the variable define before keyup event is triggered.
step 3.define timeout to the variable declared above;
<input type="text" id="input" placeholder="please type" style="padding-left:20px;"/>
<div class="data"></div>
javascript code
var textInput = document.getElementById('input');
var textdata = document.querySelector('.data');
// Init a timeout variable to be used below
var timefired = null;
// Listen for keystroke events
// Init a timeout variable to be used below
var timefired = null;// Listen for keystroke events
textInput.onkeyup = function (event) {
clearTimeout(timefired);
timefired = setTimeout(function () {
textdata.innerHTML = 'Input Value:'+ textInput.value;
}, 600);
};

This is the a simple JS code I wrote:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="pt-br" lang="pt-br">
<head><title>Submit after typing finished</title>
<script language="javascript" type="text/javascript">
function DelayedSubmission() {
var date = new Date();
initial_time = date.getTime();
if (typeof setInverval_Variable == 'undefined') {
setInverval_Variable = setInterval(DelayedSubmission_Check, 50);
}
}
function DelayedSubmission_Check() {
var date = new Date();
check_time = date.getTime();
var limit_ms=check_time-initial_time;
if (limit_ms > 800) { //Change value in milliseconds
alert("insert your function"); //Insert your function
clearInterval(setInverval_Variable);
delete setInverval_Variable;
}
}
</script>
</head>
<body>
<input type="search" onkeyup="DelayedSubmission()" id="field_id" style="WIDTH: 100px; HEIGHT: 25px;" />
</body>
</html>

Why not just use onfocusout?
https://www.w3schools.com/jsreF/event_onfocusout.asp
If it's a form, they will always leave focus of every input field in order to click the submit button so you know no input will miss out on getting its onfocusout event handler called.

Multiple timers per page
All the other answers only work for one control (my other answer included).
If you have multiple controls per page (e.g. in a shopping cart) only the last control where the user typed something will get called. In my case this is certainly not the wished behaviour - each control should have its own timer.
To solve this, you simply have to pass an ID to the function and maintain a timeoutHandles dictionary as in the following code:
Function Declaration:
var delayUserInput = (function () {
var timeoutHandles = {};
return function (id, callback, ms) {
if (timeoutHandles[id]) {
clearTimeout(timeoutHandles[id]);
}
timeoutHandles[id] = setTimeout(callback, ms);
};
})();
Function Usage:
delayUserInput('yourID', function () {
//do some stuff
}, 1000);

Here is a solution that fires after 1 second of not typing, but also fires instantly when the input is blank. This is useful when clearing search results after the user deletes the input query. This solution also supports copying and pasting into the search box. The $(() => { ... }); wrapping the top portion of code simply means "do this when the page is loaded" in simple Jquery terms.
var searchTimer;
var searchInterval = 1000;
$(() => {
$('#search-box').on('input', (event) => {
clearTimeout(searchTimer);
searchTimer = setTimeout(() => {
searchContacts(event.target.value);
}, (event.target.value.length > 0) ? searchInterval : 0);
});
});
function searchContacts(val) {
console.log('searching: ' + val);
}

You can use the onblur event to detect when the textbox loses focus:
https://developer.mozilla.org/en/DOM/element.onblur
That's not the same as "stops typing", if you care about the case where the user types a bunch of stuff and then sits there with the textbox still focused.
For that I would suggest tying a setTimeout to the onclick event, and assuming that after x amount of time with no keystrokes, the user has stopped typing.

If there is necessity for the user to move away from the field, we can use "onBlur" instead of Onchange in Javascript
<TextField id="outlined-basic" variant="outlined" defaultValue={CardValue} onBlur={cardTitleFn} />
If that is not necessary setting timer would be the good option.

for alpine.js users <input #input.debounce.500ms="fn()">

Once you detect focus on the text box, on key up do a timeout check, and reset it each time it's triggered.
When the timeout completes, do your ajax request.

If you are looking for a specific length (such as a zipcode field):
$("input").live("keyup", function( event ){
if(this.value.length == this.getAttribute('maxlength')) {
//make ajax request here after.
}
});

Not sure if my needs are just kind of weird, but I needed something similar to this and this is what I ended up using:
$('input.update').bind('sync', function() {
clearTimeout($(this).data('timer'));
$.post($(this).attr('data-url'), {value: $(this).val()}, function(x) {
if(x.success != true) {
triggerError(x.message);
}
}, 'json');
}).keyup(function() {
clearTimeout($(this).data('timer'));
var val = $.trim($(this).val());
if(val) {
var $this = $(this);
var timer = setTimeout(function() {
$this.trigger('sync');
}, 2000);
$(this).data('timer', timer);
}
}).blur(function() {
clearTimeout($(this).data('timer'));
$(this).trigger('sync');
});
Which allows me to have elements like this in my application:
<input type="text" data-url="/controller/action/" class="update">
Which get updated when the user is "done typing" (no action for 2 seconds) or goes to another field (blurs out of the element)

If you need wait until user is finished with typing use simple this:
$(document).on('change','#PageSize', function () {
//Do something after new value in #PageSize
});
Complete Example with ajax call - this working for my pager - count of item per list:
$(document).ready(function () {
$(document).on('change','#PageSize', function (e) {
e.preventDefault();
var page = 1;
var pagesize = $("#PageSize").val();
var q = $("#q").val();
$.ajax({
url: '#Url.Action("IndexAjax", "Materials", new { Area = "TenantManage" })',
data: { q: q, pagesize: pagesize, page: page },
type: 'post',
datatype: "json",
success: function (data) {
$('#tablecontainer').html(data);
// toastr.success('Pager has been changed', "Success!");
},
error: function (jqXHR, exception) {
ShowErrorMessage(jqXHR, exception);
}
});
});
});

Simple and easy to understand.
var mySearchTimeout;
$('#ctl00_mainContent_CaseSearch').keyup(function () {
clearTimeout(mySearchTimeout);
var filter = $(this).val();
mySearchTimeout = setTimeout(function () { myAjaxCall(filter); }, 700);
return true;
});

For passing parameters to your function along with ES6 syntax.
$(document).ready(() => {
let timer = null;
$('.classSelector').keydown(() => {
clearTimeout(timer);
timer = setTimeout(() => foo('params'), 500);
});
});
const foo = (params) => {
console.log(`In foo ${params}`);
}

Continue function until mouse is released

I want to be able to run the below function continuously while the mouse is down. At the moment the function excecutes once per click. I want to be able to continue running the function while mousedown and stop when the mouse is released.
$('#md').mousedown(function(e){
var pCords = e.pageY +e.pageY;
var max = $(document).height()+$(document).width();
var dg = 2*( pCords / max );
$('#div').css({ 'transform':'rotate('+dg+'deg) '});
});

This issue has been addressed in: jQuery continuous mousedown
It will involve setting up a flag that you can set to true when the first mousedown event occurs, and calling a function that only finishes once the flag is set back to false when the mouseup event occurs.

Easy way to do with time delay between execution of event handler:
var timerId = 0;
$('#md').mousedown(function(e){
timerId = setInterval(function() {
var pCords = e.pageY +e.pageY;
var max = $(document).height()+$(document).width();
var dg = 2*( pCords / max );
$('#div').css({ 'transform':'rotate('+dg+'deg) '});
}, 20); // specify the required time delay here
});
$('#md').mouseup(function(e){
clearInterval(timerId);
});

You can do it using a simple semaphore. Here's an example:
var lock = true;
$('#md').mousedown(function() {
lock = false;
setTimeout(function() {
while(!lock) {
// Do your stuff here
}
}, 0);
});
$(document).mouseup(function() {
lock = true;
});
I hope this does the trick.
The setTimeout function detaches the execution of the function and creates an asynchronous process - this makes your code non-blocking.
I'm sure there are more sophisticated ways to solve this problem. It's just that I haven't had my coffee yet. :)

like this? making a global boolean variable to track if mouse is up, then looping your function while mouse is down on that element.
var ismouseup = false;
$(document).ready(function(){
$('#md').mousedown(function(e){
ismouseup = false;
while(!ismouseup)
{
//do your thing
}
});
$('#md').mouseup(function(e){
ismouseup = true;
}
});
--edit: set ismouseup to true when mouseup. sorry.

You can use setTimeout. This will run every 1 sec when mousedown
$('#md').on({
mousedown: function () {
$(this).data('clicked', true);
var process = function() {
if ($(this).data('clicked')) {
// Do your stuff
setTimeout(process, 100);
}
};
process();
},
mouseup: function () {
$(this).data('clicked', false);
}
});

As an option you can set the handler for mousemove in mousedown and remove in mouseup as in code
function movehandler(e) {
var pCords = e.pageY + e.pageY;
var max = $('#md').height();
var dg = 20 * (pCords / max);
$('#md').css({
'transform': 'rotate(' + dg + 'deg) '
});
}
$('#md').mousedown(function (e) {
$('body').on('mousemove', movehandler);
});
$('#md').mouseup(function (e) {
$('body').off('mousemove');
});
$('body').mouseleave(function (e) {
$('body').off('mousemove');
});
Jsfiffle Example is not ideally written but you can get the idea
EDIT: Note that $('body').on('mousemove', might not be sufficient dependent on your markup.

Repeat code every x seconds but not if [insert check here]

This is a followup to this question, where I found out how to make code be repeated every x seconds. Is it possible to make an event that can change this? I.e. I have a checkbox which is meant to control whether this is repeated or not, so I figured I'd need something like this:
$(checkbox).bind("change", function() {
switch(whether if it is ticked or not) {
case [ticked]:
// Make the code repeat, while preserving the ability to stop it repeating
case [unticked]:
// Make the code stop repeating, while preserving the ability to start again
}
});
I have no idea what I could put in the cases.

You can do it by assigning your setInterval function to a variable.
var interval = setInterval(function() { }, 1000);
and then you can stop setInterval by
clearInterval(interval);
p.s.
to start your interval you need to call var interval = setInterval(function() { }, 1000); again

You can either stop and start the interval:
var timer;
function start() {
timer = window.setInterval(function(){
// do something
}, 1000);
}
function stop() {
window.clearInterval(timer);
}
start();
$(checkbox).bind("change", function() {
if ($(this).is(':checked')) {
start();
} else {
stop();
}
});
Or you can have a flag causing the interval to skip the code:
var enabled = true;
var timer = window.setInterval(function(){
if (!enabled) {
// do something
}
}, 1000);
$(checkbox).bind("change", function() {
enabled = $(this).is(':checked');
});

function fooFunc() {
$('#foo').text(+new Date());
}
var id;
var shouldBeStopped = false;
$('input').change(function() {
if (shouldBeStopped)
clearInterval(id);
else
id = setInterval(fooFunc, 200);
shouldBeStopped = !shouldBeStopped;
});​
Live DEMO

jQuery scroll() detect when user stops scrolling

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.

$(window).scroll(function() {
clearTimeout($.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?!)

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));

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) );
}
};
})();

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

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
}))

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.

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

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.
}

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()
)

please check the jquery mobile scrollstop event
$(document).on("scrollstop",function(){
alert("Stopped scrolling!");
});

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 */
}
});

This should work:
var Timer;
$('.Scroll_Table_Div').on("scroll",function()
{
// do somethings
clearTimeout(Timer);
Timer = setTimeout(function()
{
console.log('scrolling is stop');
},50);
});

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>

Javascript "while hovered" loop

Can anybody help me on this one...I have a button which when is hovered, triggers an action. But I'd like it to repeat it for as long as the button is hovered.
I'd appreciate any solution, be it in jquery or pure javascript - here is how my code looks at this moment (in jquery):
var scrollingposition = 0;
$('#button').hover(function(){
++scrollingposition;
$('#object').css("right", scrollingposition);
});
Now how can i put this into some kind of while loop, so that #object is moving px by px for as #button is hovered, not just when the mouse enters it?

OK... another stab at the answer:
$('myselector').each(function () {
var hovered = false;
var loop = window.setInterval(function () {
if (hovered) {
// ...
}
}, 250);
$(this).hover(
function () {
hovered = true;
},
function () {
hovered = false;
}
);
});
The 250 means the task repeats every quarter of a second. You can decrease this number to make it faster or increase it to make it slower.

Nathan's answer is a good start, but you should also use window.clearInterval when the mouse leaves the element (mouseleave event) to cancel the repeated action which was set up using setInterval(), because this way the "loop" is running only when the mouse pointer enters the element (mouseover event).
Here is a sample code:
function doSomethingRepeatedly(){
// do this repeatedly when hovering the element
}
var intervalId;
$(document).ready(function () {
$('#myelement').hover(function () {
var intervalDelay = 10;
// call doSomethingRepeatedly() function repeatedly with 10ms delay between the function calls
intervalId = setInterval(doSomethingRepeatedly, intervalDelay);
}, function () {
// cancel calling doSomethingRepeatedly() function repeatedly
clearInterval(intervalId);
});
});
I created a sample code on jsFiddle which demonstrates how to scroll the background-image of an element left-to-right and then backwards on hover with the code shown above:
http://jsfiddle.net/Sk8erPeter/HLT3J/15/

If its an animation you can "stop" an animation half way through. So it looks like you're moving something to the left so you could do:
var maxScroll = 9999;
$('#button').hover(
function(){ $('#object').animate({ "right":maxScroll+"px" }, 10000); },
function(){ $('#object').stop(); } );

var buttonHovered = false;
$('#button').hover(function () {
buttonHovered = true;
while (buttonHovered) {
...
}
},
function () {
buttonHovered = false;
});
If you want to do this for multiple objects, it might be better to make it a bit more object oriented than a global variable though.
Edit:
Think the best way of dealing with multiple objects is to put it in an .each() block:
$('myselector').each(function () {
var hovered = false;
$(this).hover(function () {
hovered = true;
while (hovered) {
...
}
},
function () {
hovered = false;
});
});
Edit2:
Or you could do it by adding a class:
$('selector').hover(function () {
$(this).addClass('hovered');
while ($(this).hasClass('hovered')) {
...
}
}, function () {
$(this).removeClass('hovered');
});

var scrollingposition = 0;
$('#button').hover(function(){
var $this = $(this);
var $obj = $("#object");
while ( $this.is(":hover") ) {
scrollingposition += 1;
$obj.css("right", scrollingposition);
}
});