window.onresize fires twice - javascript

I'm new to js. Please, don't kick painfully.
I have this code
window.onresize=function() {alert(1);};
When I resize any browser`s window, this function fires twice. Why? And how to rewrite this code that code will fire once.
Thanx in advance.

You need a timeout to bundle the resize events.
var res;
window.onresize=function() {
if (res){clearTimeout(res)};
res = setTimeout(function(){console.log("resize triggered");},100);
};
live Example

This event will fire multiple times in different browsers (some once you've finished the the resize, others during).
One way to get around this is to wait a certain amount of time (say half a second) after the event fires, to see if there are further updates. If not, you can proceed with the alert.
e.g.
var resizeTimer;
window.onresize = function(){
if (resizeTimer){
clearTimeout(resizeTimer);
}
resizeTimer = setTimeout(function(){
alert(1);
}, 500);
};
See it work on this fiddle.

To prevent function from "firing" the same result more than once when user resize
var doc = document; //To access the dom only once
var cWidth = doc.body.clientWidth;
var newWidth = cWidth; //If you want a log to show at startup, change to: newWidth = 0
window.onresize = function (){
newWidth = doc.body.clientWidth;
if(cWidth != newWidth){
cWidth = newWidth;
console.log("clientWidth:", cWidth); //instead of alert(cWidth);
};
};

I propose other solution because I don't like the timeouts,
`var resized;
window.onresize = function () {
if(resized){
resized = false;
}
else{
resized = true;
alert('resize');
}
};`

Related

Recall JS function on window resize

I am extremely new to JS, any help with this question is greatly appreciated.
I have the following bit of JS:
var isMobile = false;
if(Modernizr.mq('only all and (max-width: 1024px)') ) {
isMobile = true;
}
if (isMobile === false)
/* desired function: */
slider.ev.on('rsAfterSlideChange', playSlideVideo);
playSlideVideo();
}
Which indeed works as intended if the browser window loads below or above max-width: 1024px. The problem is that I would like my functions to run or stop if the user changes the size of their window after the page loads.
How can I go about setting that up?
This is amazing, thank you! Specially for explaining commenting your code along the way. Im 80% there. the script works when going from small window to big, but does not work from big to small. any thoughts on how I can fix? This is all of my code:
var slider = $(".royalSlider").data('royalSlider'),
prevSlideVideo,
playSlideVideo = function() {
if(prevSlideVideo) {
prevSlideVideo.pause();
}
var video = slider.currSlide.content.find('video');
if(video.length) {
prevSlideVideo = video[0];
prevSlideVideo.play();
} else {
prevSlideVideo = null;
}
};
var $window = $(window); // have a reference to window
var isMobile = false; // boolean to check for mobile
var timer = 0;
function updateSlider() {
if (!isMobile) {
/* desired shenanigans: */
slider.ev.on('rsAfterSlideChange', playSlideVideo);
playSlideVideo();
}
}
$window.on("resize.slider", function() {
// delay execution to 300ms after the last resize event
timer = setTimeout(function() {
clearTimeout(timer);
isMobile = Modernizr.mq('only all and (max-width: 1024px)'); // update isMobile with mq value
updateSlider(); // run function on resize
}, 300);
}).trigger("resize.slider"); // trigger this event so you dont have to explictly call updateSlider();
update
I would doubt the isMobile = Modernizr.mq('only all and (max-width: 1024px)'); part (even though it seems fine)
Also, it appears that you're assigning events to slider widget. There could be a case where multiple resize events would end up attaching multiple events 'rsAfterSlideChange' to the slider.
Looking at the api there doesn't seem to be an off method.
So, keeping above in mind. could you try something like below:
var $window = $(window); // have a reference to window
var isMobile = false; // boolean to check for mobile
var timer = 0;
var slider = $(".royalSlider").data('royalSlider'); // slider instance
var prevSlideVideo;
var playSlideVideo = function() {
if(prevSlideVideo) {
prevSlideVideo.pause();
}
var video = slider.currSlide.content.find('video');
if(video.length) {
prevSlideVideo = video[0];
prevSlideVideo.play();
} else {
prevSlideVideo = null;
}
};
// Looking at the [api](http://dimsemenov.com/plugins/royal-slider/documentation/#api) there doesn't seem to be an ```off``` method.
// So it is probably safe to attach event only once.
slider.ev.on('rsAfterSlideChange', playSlideVideo);
$window.on("resize.slider", function() {
// delay execution to 300ms after the last resize event
timer = setTimeout(function() {
clearTimeout(timer);
// quick and dirty check of window width instead of match media, this is unreliable but should do the job for now
if ($window.width() < 1024) {
playSlideVideo();
}
// updateSlider(); // dont need this anymore as you're calling ```playSlideVideo()``` straight away
}, 300);
}).trigger("resize.slider"); // trigger this event so you dont have to explictly call updateSlider();
There are many ways to do it.
Heres a quick way:
var $window = $(window); // have a reference to window
var isMobile = false; // boolean to check for mobile
function updateSlider() {
if (!isMobile) {
/* desired shenanigans: */
slider.ev.on('rsAfterSlideChange', playSlideVideo);
playSlideVideo();
}
}
$window.on("resize.slider", function() {
isMobile = Modernizr.mq('only all and (max-width: 1024px)'); // update isMobile with mq value
updateSlider(); // run function on resize
}).trigger("resize.slider"); // trigger this event so you don't have to explicitly call updateSlider();
Interesting thing with resize events is that they will fire many times when window is resized, there are many ways to throttle this event, below is one way
var $window = $(window); // have a reference to window
var isMobile = false; // boolean to check for mobile
var timer = 0;
function updateSlider() {
if (!isMobile) {
/* desired shenanigans: */
slider.ev.on('rsAfterSlideChange', playSlideVideo);
playSlideVideo();
}
}
$window.on("resize.slider", function() {
// delay execution to 300ms after the last resize event
timer = setTimeout(function() {
clearTimeout(timer);
isMobile = Modernizr.mq('only all and (max-width: 1024px)'); // update isMobile with mq value
updateSlider(); // run funtion on resize
}, 300);
}).trigger("resize.slider"); // trigger this event so you dont have to explictly call updateSlider();
I haven't tested above code (maybe provide a fiddle?) but should put you in right direction. Let me know if anything is unclear.
Good luck

Why jQuery doing unwanted multiple actions of single command?

When i resize browser the it gives multiple alerts. I used "return false" not working.
If I used unbind()/unbind('resize') then it works but it creates an other problem- the resize() function stops working from second time browser/window resize.
My code-
<script src="jquery.min.js"></script>
<script type="text/javascript">
$(document).ready(function(e) {
alert($(".myclass").parent().width());
$(window).bind('resize',function() {
alert($(".myclass").parent().width());
});
});
</script>
<section class="myclass"></section>
This is not an issue with jQuery, but on the browser's implementation of resize.
Depending which browser you use it may trigger intermediate resizes, or a resize when your mouse is released only.
Because the resize triggers everytime the browser changes.
If you are resizing 100 pixels it can trigger up to 100 times.
Something like this should work and trigger only once you stopped resizing the window:
var resizing = false, stopedResizing = true;
$(window).bind('resize',function() {
if(!resizing){
console.log("started resizing. Width = " + $(".myclass").parent().width());
resizing = true;
}
stopedResizing = false;
setTimeout(function(){
if(!stopedResizing){
stopedResizing = true;
setTimeout(function(){
if(stopedResizing && resizing){
resizing = false;
console.log('Stoped resizing. Width = ' + $(".myclass").parent().width());
}
}, 500);
}
}, 500);
});
You could do something like:
$(document).ready(function(e) {
alert($(".myclass").parent().width());
var lastTime = 0;
$(window).bind('resize',function() {
var currentTime = new Date().time();
if(currentTime > lastTime + 5000)
alert($(".myclass").parent().width());
lastTime = currentTime;
});
});
...so that it will only fire on resizes at least 5 seconds apart. Normally though, you'd want to act when resizing stops, not when it starts.
This code fires ones on mouseover of the window after the a resize event as occurred.
$(document).ready(function() {
var windowResized = false;
function callFunction() {
console.log("I am called once after window resize");
}
$(window).mouseover(function() {
if (windowResized == true) {
callFunction();
windowResized = false;
}
})
$(window).resize(function() {
windowResized = true;
});
})

How to wait for the 'end' of 'resize' event and only then perform an action?

So I currently use something like:
$(window).resize(function(){resizedw();});
But this gets called many times while resizing process goes on. Is it possible to catch an event when it ends?
You can use setTimeout() and clearTimeout()
function resizedw(){
// Haven't resized in 100ms!
}
var doit;
window.onresize = function(){
clearTimeout(doit);
doit = setTimeout(resizedw, 100);
};
Code example on jsfiddle.
I had luck with the following recommendation: http://forum.jquery.com/topic/the-resizeend-event
Here's the code so you don't have to dig through his post's link & source:
var rtime;
var timeout = false;
var delta = 200;
$(window).resize(function() {
rtime = new Date();
if (timeout === false) {
timeout = true;
setTimeout(resizeend, delta);
}
});
function resizeend() {
if (new Date() - rtime < delta) {
setTimeout(resizeend, delta);
} else {
timeout = false;
alert('Done resizing');
}
}
Thanks sime.vidas for the code!
This is the code that I write according to #Mark Coleman answer:
$(window).resize(function() {
clearTimeout(window.resizedFinished);
window.resizedFinished = setTimeout(function(){
console.log('Resized finished.');
}, 250);
});
Thanks Mark!
Internet Explorer provides a resizeEnd event. Other browsers will trigger the resize event many times while you're resizing.
There are other great answers here that show how to use setTimeout and the .throttle, .debounce methods from lodash and underscore, so I will mention Ben Alman's throttle-debounce jQuery plugin which accomplishes what you're after.
Suppose you have this function that you want to trigger after a resize:
function onResize() {
console.log("Resize just happened!");
};
Throttle Example
In the following example, onResize() will only be called once every 250 milliseconds during a window resize.
$(window).resize( $.throttle( 250, onResize) );
Debounce Example
In the following example, onResize() will only be called once at the end of a window resizing action. This achieves the same result that #Mark presents in his answer.
$(window).resize( $.debounce( 250, onResize) );
There is an elegant solution using the Underscore.js So, if you are using it in your project you can do the following -
$( window ).resize( _.debounce( resizedw, 500 ) );
This should be enough :) But, If you are interested to read more on that, you can check my blog post - http://rifatnabi.com/post/detect-end-of-jquery-resize-event-using-underscore-debounce(deadlink)
There is a much simpler method to execute a function at the end of the resize than calculate the delta time between two calls, simply do it like this :
var resizeId;
$(window).resize(function() {
clearTimeout(resizeId);
resizeId = setTimeout(resizedEnded, 500);
});
function resizedEnded(){
...
}
And the equivalent for Angular2 :
private resizeId;
#HostListener('window:resize', ['$event'])
onResized(event: Event) {
clearTimeout(this.resizeId);
this.resizeId = setTimeout(() => {
// Your callback method here.
}, 500);
}
For the angular method, use the () => { } notation in the setTimeout to preserve the scope, otherwise you will not be able to make any function calls or use this.
One solution is extend jQuery with a function, e.g.: resized
$.fn.resized = function (callback, timeout) {
$(this).resize(function () {
var $this = $(this);
if ($this.data('resizeTimeout')) {
clearTimeout($this.data('resizeTimeout'));
}
$this.data('resizeTimeout', setTimeout(callback, timeout));
});
};
Sample usage:
$(window).resized(myHandler, 300);
You can store a reference id to any setInterval or setTimeout. Like this:
var loop = setInterval(func, 30);
// some time later clear the interval
clearInterval(loop);
To do this without a "global" variable you can add a local variable to the function itself. Ex:
$(window).resize(function() {
clearTimeout(this.id);
this.id = setTimeout(doneResizing, 500);
});
function doneResizing(){
$("body").append("<br/>done!");
}
You can use setTimeout() and clearTimeout() in conjunction with jQuery.data:
$(window).resize(function() {
clearTimeout($.data(this, 'resizeTimer'));
$.data(this, 'resizeTimer', setTimeout(function() {
//do something
alert("Haven't resized in 200ms!");
}, 200));
});
Update
I wrote an extension to enhance jQuery's default on (& bind)-event-handler. It attaches an event handler function for one or more events to the selected elements if the event was not triggered for a given interval. This is useful if you want to fire a callback only after a delay, like the resize event, or else.
https://github.com/yckart/jquery.unevent.js
;(function ($) {
var methods = { on: $.fn.on, bind: $.fn.bind };
$.each(methods, function(k){
$.fn[k] = function () {
var args = [].slice.call(arguments),
delay = args.pop(),
fn = args.pop(),
timer;
args.push(function () {
var self = this,
arg = arguments;
clearTimeout(timer);
timer = setTimeout(function(){
fn.apply(self, [].slice.call(arg));
}, delay);
});
return methods[k].apply(this, isNaN(delay) ? arguments : args);
};
});
}(jQuery));
Use it like any other on or bind-event handler, except that you can pass an extra parameter as a last:
$(window).on('resize', function(e) {
console.log(e.type + '-event was 200ms not triggered');
}, 200);
http://jsfiddle.net/ARTsinn/EqqHx/
Mark Coleman's answer is certainly far better than the selected answer, but if you want to avoid the global variable for the timeout ID (the doit variable in Mark's answer), you could do one of the following:
(1) Use a an immediately invoked function expression (IIFE) to create a closure.
$(window).resize((function() { // This function is immediately invoked
// and returns the closure function.
var timeoutId;
return function() {
clearTimeout(timeoutId);
timeoutId = setTimeout(function() {
timeoutId = null; // You could leave this line out.
// Code to execute on resize goes here.
}, 100);
};
})());
(2) Use a property of the event handler function.
$(window).resize(function() {
var thisFunction = arguments.callee;
clearTimeout(thisFunction.timeoutId);
thisFunction.timeoutId = setTimeout(function() {
thisFunction.timeoutId = null; // You could leave this line out.
// Code to execute on resize goes here.
}, 100);
});
This is what I use for delaying repeated actions, it can be called in multiple places in your code:
function debounce(func, wait, immediate) {
var timeout;
return function() {
var context = this, args = arguments;
var later = function() {
timeout = null;
if (!immediate) func.apply(context, args);
};
var callNow = immediate && !timeout;
clearTimeout(timeout);
timeout = setTimeout(later, wait);
if (callNow) func.apply(context, args);
};
};
Usage:
$(window).resize(function () {
debounce(function() {
//...
}, 500);
});
ResizeStart and ResizeEnd events for window
http://jsfiddle.net/04fLy8t4/
I implemented a function which trigs two events on the user DOM element:
resizestart
resizeend
Code:
var resizeEventsTrigger = (function () {
function triggerResizeStart($el) {
$el.trigger('resizestart');
isStart = !isStart;
}
function triggerResizeEnd($el) {
clearTimeout(timeoutId);
timeoutId = setTimeout(function () {
$el.trigger('resizeend');
isStart = !isStart;
}, delay);
}
var isStart = true;
var delay = 200;
var timeoutId;
return function ($el) {
isStart ? triggerResizeStart($el) : triggerResizeEnd($el);
};
})();
$("#my").on('resizestart', function () {
console.log('resize start');
});
$("#my").on('resizeend', function () {
console.log('resize end');
});
window.onresize = function () {
resizeEventsTrigger( $("#my") );
};
This is a modification to Dolan's code above, I've added a feature which checks the window size at the start of the resize and compares it to the size at the end of the resize, if size is either bigger or smaller than the margin (eg. 1000) then it reloads.
var rtime = new Date(1, 1, 2000, 12,00,00);
var timeout = false;
var delta = 200;
var windowsize = $window.width();
var windowsizeInitial = $window.width();
$(window).on('resize',function() {
windowsize = $window.width();
rtime = new Date();
if (timeout === false) {
timeout = true;
setTimeout(resizeend, delta);
}
});
function resizeend() {
if (new Date() - rtime < delta) {
setTimeout(resizeend, delta);
return false;
} else {
if (windowsizeInitial > 1000 && windowsize > 1000 ) {
setTimeout(resizeend, delta);
return false;
}
if (windowsizeInitial < 1001 && windowsize < 1001 ) {
setTimeout(resizeend, delta);
return false;
} else {
timeout = false;
location.reload();
}
}
windowsizeInitial = $window.width();
return false;
}
Here is VERY simple script to trigger both a 'resizestart' and 'resizeend' event on the window object.
There is no need to muck around with dates and times.
The d variable represents the number of milliseconds between resize events before triggering the resize end event, you can play with this to change how sensitive the end event is.
To listen to these events all you need to do is:
resizestart: $(window).on('resizestart', function(event){console.log('Resize Start!');});
resizeend:
$(window).on('resizeend', function(event){console.log('Resize End!');});
(function ($) {
var d = 250, t = null, e = null, h, r = false;
h = function () {
r = false;
$(window).trigger('resizeend', e);
};
$(window).on('resize', function (event) {
e = event || e;
clearTimeout(t);
if (!r) {
$(window).trigger('resizestart', e);
r = true;
}
t = setTimeout(h, d);
});
}(jQuery));
i wrote a litte wrapper function on my own...
onResize = function(fn) {
if(!fn || typeof fn != 'function')
return 0;
var args = Array.prototype.slice.call(arguments, 1);
onResize.fnArr = onResize.fnArr || [];
onResize.fnArr.push([fn, args]);
onResize.loop = function() {
$.each(onResize.fnArr, function(index, fnWithArgs) {
fnWithArgs[0].apply(undefined, fnWithArgs[1]);
});
};
$(window).on('resize', function(e) {
window.clearTimeout(onResize.timeout);
onResize.timeout = window.setTimeout("onResize.loop();", 300);
});
};
Here is the usage:
var testFn = function(arg1, arg2) {
console.log('[testFn] arg1: '+arg1);
console.log('[testFn] arg2: '+arg2);
};
// document ready
$(function() {
onResize(testFn, 'argument1', 'argument2');
});
(function(){
var special = jQuery.event.special,
uid1 = 'D' + (+new Date()),
uid2 = 'D' + (+new Date() + 1);
special.resizestart = {
setup: function() {
var timer,
handler = function(evt) {
var _self = this,
_args = arguments;
if (timer) {
clearTimeout(timer);
} else {
evt.type = 'resizestart';
jQuery.event.handle.apply(_self, _args);
}
timer = setTimeout( function(){
timer = null;
}, special.resizestop.latency);
};
jQuery(this).bind('resize', handler).data(uid1, handler);
},
teardown: function(){
jQuery(this).unbind( 'resize', jQuery(this).data(uid1) );
}
};
special.resizestop = {
latency: 200,
setup: function() {
var timer,
handler = function(evt) {
var _self = this,
_args = arguments;
if (timer) {
clearTimeout(timer);
}
timer = setTimeout( function(){
timer = null;
evt.type = 'resizestop';
jQuery.event.handle.apply(_self, _args);
}, special.resizestop.latency);
};
jQuery(this).bind('resize', handler).data(uid2, handler);
},
teardown: function() {
jQuery(this).unbind( 'resize', jQuery(this).data(uid2) );
}
};
})();
$(window).bind('resizestop',function(){
//...
});
Well, as far as the window manager is concerned, each resize event is its own message, with a distinct beginning and end, so technically, every time the window is resized, it is the end.
Having said that, maybe you want to set a delay to your continuation? Here's an example.
var t = -1;
function doResize()
{
document.write('resize');
}
$(document).ready(function(){
$(window).resize(function(){
clearTimeout(t);
t = setTimeout(doResize, 1000);
});
});
I guess my case might be different from some others but I had a problem only with orientation change on iOS but wanted the resize event to run immediately. I used the ScreenOrientation API:
screen.orientation.addEventListener('change', (e) => {});
I took a slightly different tack and relied on mouseUp as the end of the resize event. trackSize is called on documentReady and the initial value of wide is set then, too.
var THRESHOLD = 784;
var TALL = 125, SHORT = 50;
var wide = (window.document.body.clientWidth >= THRESHOLD );
function trackSize() {
if( !wide ) {
setHeight( TALL );
} else {
setHeight( SHORT );
}
parent.window.addEventListener('resize', onResize);
}
function onResize(e) {
parent.window.removeEventListener('resize', onResize);
parent.window.addEventListener('mouseup', onMouseUp) ;
}
function onMouseUp(e) {
parent.window.removeEventListener('mouseup', onMouseUp);
wide = (window.document.body.clientWidth >= THRESHOLD);
trackSize();
}
After having set our window's initial height, we begin listening for a resize event. When it starts, we stop listening and start listening for the mouseUp event. Thus, we know that mouseUp will end the resizing. In mouseUp, we stop listening and set a toggle based on the window's width, then loop back to trackSize.
trackSize starts by setting the window's height based on the toggle -- if below the threshold, we increase height (because Bootstrap columns stack at small widths), otherwise set to standard. And then we listen again for the next resize event.
CAVEAT: This solution doesn't really work for resizing instantly using the maximize or restore window buttons. Maybe adding a test like isMouseDown and bypassing the mouse listener would suffice - I haven't yet tested that.
since the selected answer didn't actually work .. and if you're not using jquery here is a simple throttle function with an example of how to use it with window resizing
function throttle(end,delta) {
var base = this;
base.wait = false;
base.delta = 200;
base.end = end;
base.trigger = function(context) {
//only allow if we aren't waiting for another event
if ( !base.wait ) {
//signal we already have a resize event
base.wait = true;
//if we are trying to resize and we
setTimeout(function() {
//call the end function
if(base.end) base.end.call(context);
//reset the resize trigger
base.wait = false;
}, base.delta);
}
}
};
var windowResize = new throttle(function() {console.log('throttle resize');},200);
window.onresize = function(event) {
windowResize.trigger();
}
this worked for me as I did not want to use any plugins.
$(window).resize(function() {
var originalWindowSize = 0;
var currentWidth = 0;
var setFn = function () {
originalWindowSize = $(window).width();
};
var checkFn = function () {
setTimeout(function () {
currentWidth = $(window).width();
if (currentWidth === originalWindowSize) {
console.info("same? = yes")
// execute code
} else {
console.info("same? = no");
// do nothing
}
}, 500)
};
setFn();
checkFn();
});
On window re-size invoke "setFn" which gets width of window and save as "originalWindowSize". Then invoke "checkFn" which after 500ms (or your preference) gets the current window size, and compares the original to the current, if they are not the same, then the window is still being re-sized. Don't forget to remove console messages in production, and (optional) can make "setFn" self executing.
var resizeTimer;
$( window ).resize(function() {
if(resizeTimer){
clearTimeout(resizeTimer);
}
resizeTimer = setTimeout(function() {
//your code here
resizeTimer = null;
}, 200);
});
This worked for what I was trying to do in chrome. This won't fire the callback until 200ms after last resize event.
UPDATE!
Better alternative also created by me is here:
https://stackoverflow.com/a/23692008/2829600
(supports "delete functions")
ORIGINAL POST:
I wrote this simple function for handling delay in execution, useful inside jQuery .scroll() and .resize() So callback_f will run only once for specific id string.
function delay_exec( id, wait_time, callback_f ){
// IF WAIT TIME IS NOT ENTERED IN FUNCTION CALL,
// SET IT TO DEFAULT VALUE: 0.5 SECOND
if( typeof wait_time === "undefined" )
wait_time = 500;
// CREATE GLOBAL ARRAY(IF ITS NOT ALREADY CREATED)
// WHERE WE STORE CURRENTLY RUNNING setTimeout() FUNCTION FOR THIS ID
if( typeof window['delay_exec'] === "undefined" )
window['delay_exec'] = [];
// RESET CURRENTLY RUNNING setTimeout() FUNCTION FOR THIS ID,
// SO IN THAT WAY WE ARE SURE THAT callback_f WILL RUN ONLY ONE TIME
// ( ON LATEST CALL ON delay_exec FUNCTION WITH SAME ID )
if( typeof window['delay_exec'][id] !== "undefined" )
clearTimeout( window['delay_exec'][id] );
// SET NEW TIMEOUT AND EXECUTE callback_f WHEN wait_time EXPIRES,
// BUT ONLY IF THERE ISNT ANY MORE FUTURE CALLS ( IN wait_time PERIOD )
// TO delay_exec FUNCTION WITH SAME ID AS CURRENT ONE
window['delay_exec'][id] = setTimeout( callback_f , wait_time );
}
// USAGE
jQuery(window).resize(function() {
delay_exec('test1', 1000, function(){
console.log('1st call to delay "test1" successfully executed!');
});
delay_exec('test1', 1000, function(){
console.log('2nd call to delay "test1" successfully executed!');
});
delay_exec('test1', 1000, function(){
console.log('3rd call to delay "test1" successfully executed!');
});
delay_exec('test2', 1000, function(){
console.log('1st call to delay "test2" successfully executed!');
});
delay_exec('test3', 1000, function(){
console.log('1st call to delay "test3" successfully executed!');
});
});
/* RESULT
3rd call to delay "test1" successfully executed!
1st call to delay "test2" successfully executed!
1st call to delay "test3" successfully executed!
*/
var flag=true;
var timeloop;
$(window).resize(function(){
rtime=new Date();
if(flag){
flag=false;
timeloop=setInterval(function(){
if(new Date()-rtime>100)
myAction();
},100);
}
})
function myAction(){
clearInterval(timeloop);
flag=true;
//any other code...
}
I don't know is my code work for other but it's really do a great job for me. I got this idea by analyzing Dolan Antenucci code because his version is not work for me and I really hope it'll be helpful to someone.
var tranStatus = false;
$(window).resizeend(200, function(){
$(".cat-name, .category").removeAttr("style");
//clearTimeout(homeResize);
$("*").one("webkitTransitionEnd otransitionend oTransitionEnd msTransitionEnd transitionend",function(event) {
tranStatus = true;
});
processResize();
});
function processResize(){
homeResize = setInterval(function(){
if(tranStatus===false){
console.log("not yet");
$("*").one("webkitTransitionEnd otransitionend oTransitionEnd msTransitionEnd transitionend",function(event) {
tranStatus = true;
});
}else{
text_height();
clearInterval(homeResize);
}
},200);
}
I wrote a function that passes a function when wrapped in any resize event. It uses an interval so that the resize even isn't constantly creating timeout events. This allows it to perform independently of the resize event other than a log entry that should be removed in production.
https://github.com/UniWrighte/resizeOnEnd/blob/master/resizeOnEnd.js
$(window).resize(function(){
//call to resizeEnd function to execute function on resize end.
//can be passed as function name or anonymous function
resizeEnd(function(){
});
});
//global variables for reference outside of interval
var interval = null;
var width = $(window).width();
var numi = 0; //can be removed in production
function resizeEnd(functionCall){
//check for null interval
if(!interval){
//set to new interval
interval = setInterval(function(){
//get width to compare
width2 = $(window).width();
//if stored width equals new width
if(width === width2){
//clear interval, set to null, and call passed function
clearInterval(interval);
interval = null; //precaution
functionCall();
}
//set width to compare on next interval after half a second
width = $(window).width();
}, 500);
}else{
//logging that should be removed in production
console.log("function call " + numi++ + " and inteval set skipped");
}
}

Event when user stops scrolling

I'd like to do some fancy jQuery stuff when the user scrolls the page. But I have no idea how to tackle this problem, since there is only the scroll() method.
Any ideas?
You can make the scroll() have a time-out that gets overwritten each times the user scrolls. That way, when he stops after a certain amount of milliseconds your script is run, but if he scrolls in the meantime the counter will start over again and the script will wait until he is done scrolling again.
Update:
Because this question got some action again I figured I might as well update it with a jQuery extension that adds a scrollEnd event
// extension:
$.fn.scrollEnd = function(callback, timeout) {
$(this).on('scroll', function(){
var $this = $(this);
if ($this.data('scrollTimeout')) {
clearTimeout($this.data('scrollTimeout'));
}
$this.data('scrollTimeout', setTimeout(callback,timeout));
});
};
// how to call it (with a 1000ms timeout):
$(window).scrollEnd(function(){
alert('stopped scrolling');
}, 1000);
<script src="https://code.jquery.com/jquery-3.5.1.min.js" integrity="sha256-9/aliU8dGd2tb6OSsuzixeV4y/faTqgFtohetphbbj0=" crossorigin="anonymous"></script>
<div style="height: 200vh">
Long div
</div>
Here is a simple example using setTimeout to fire a function when the user stops scrolling:
(function() {
var timer;
$(window).bind('scroll',function () {
clearTimeout(timer);
timer = setTimeout( refresh , 150 );
});
var refresh = function () {
// do stuff
console.log('Stopped Scrolling');
};
})();
The timer is cleared while the scroll event is firing. Once scrolling stops, the refresh function is fired.
Or as a plugin:
$.fn.afterwards = function (event, callback, timeout) {
var self = $(this), delay = timeout || 16;
self.each(function () {
var $t = $(this);
$t.on(event, function(){
if ($t.data(event+'-timeout')) {
clearTimeout($t.data(event+'-timeout'));
}
$t.data(event + '-timeout', setTimeout(function () { callback.apply($t); },delay));
})
});
return this;
};
To fire callback after 100ms of the last scroll event on a div (with namespace):
$('div.mydiv').afterwards('scroll.mynamespace', function(e) {
// do stuff when stops scrolling
$(this).addClass('stopped');
}, 100
);
I use this for scroll and resize.
Here is another more generic solution based on the same ideas mentioned:
var delayedExec = function(after, fn) {
var timer;
return function() {
timer && clearTimeout(timer);
timer = setTimeout(fn, after);
};
};
var scrollStopper = delayedExec(500, function() {
console.log('stopped it');
});
document.getElementById('box').addEventListener('scroll', scrollStopper);
I had the need to implement onScrollEnd event discussed hear as well.
The idea of using timer works for me.
I implement this using JavaScript Module Pattern:
var WindowCustomEventsModule = (function(){
var _scrollEndTimeout = 30;
var _delayedExec = function(callback){
var timer;
return function(){
timer && clearTimeout(timer);
timer = setTimeout(callback, _scrollEndTimeout);
}
};
var onScrollEnd = function(callback) {
window.addEventListener('scroll', _delayedExec(callback), false);
};
return {
onScrollEnd: onScrollEnd
}
})();
// usage example
WindowCustomEventsModule.onScrollEnd(function(){
//
// do stuff
//
});
Hope this will help / inspire someone
Why so complicated? As the documentation points out, this http://jsfiddle.net/x3s7F/9/ works!
$('.frame').scroll(function() {
$('.back').hide().fadeIn(100);
}
http://api.jquery.com/scroll/.
Note: The scroll event on Windows Chrome is differently to all others. You need to scroll fast to get the same as result as in e.g. FF. Look at https://liebdich.biz/back.min.js the "X" function.
Some findings from my how many ms a scroll event test:
Safari, Mac FF, Mac Chrome: ~16ms an event.
Windows FF: ~19ms an event.
Windows Chrome: up to ~130ms an event, when scrolling slow.
Internet Explorer: up to ~110ms an event.
http://jsfiddle.net/TRNCFRMCN/1Lygop32/4/.
There is no such event as 'scrollEnd'. I recommend that you check the value returned by scroll() every once in a while (say, 200ms) using setInterval, and record the delta between the current and the previous value. If the delta becomes zero, you can use it as your event.
There are scrollstart and scrollstop functions that are part of jquery mobile.
Example using scrollstop:
$(document).on("scrollstop",function(){
alert("Stopped scrolling!");
});
Hope this helps someone.
The scrollEnd event is coming. It's currently experimental and is only supported by Firefox. See the Mozilla documentation here - https://developer.mozilla.org/en-US/docs/Web/API/Document/scrollend_event
Once it's supported by more browsers, you can use it like this...
document.onscrollend = (event) => {
console.log('Document scrollend event fired!');
};
I pulled some code out of a quick piece I cobbled together that does this as an example (note that scroll.chain is an object containing two arrays start and end that are containers for the callback functions). Also note that I am using jQuery and underscore here.
$('body').on('scroll', scrollCall);
scrollBind('end', callbackFunction);
scrollBind('start', callbackFunction);
var scrollCall = function(e) {
if (scroll.last === false || (Date.now() - scroll.last) <= 500) {
scroll.last = Date.now();
if (scroll.timeout !== false) {
window.clearTimeout(scroll.timeout);
} else {
_(scroll.chain.start).each(function(f){
f.call(window, {type: 'start'}, e.event);
});
}
scroll.timeout = window.setTimeout(self.scrollCall, 550, {callback: true, event: e});
return;
}
if (e.callback !== undefined) {
_(scroll.chain.end).each(function(f){
f.call(window, {type: 'end'}, e.event);
});
scroll.last = false;
scroll.timeout = false;
}
};
var scrollBind = function(type, func) {
type = type.toLowerCase();
if (_(scroll.chain).has(type)) {
if (_(scroll.chain[type]).indexOf(func) === -1) {
scroll.chain[type].push(func);
return true;
}
return false;
}
return false;
}

How to use both onclick and ondblclick on an element?

I have an element on my page that I need to attach onclick and ondblclick event handlers to. When a single click happens, it should do something different than a double-click. When I first started trying to make this work, my head started spinning. Obviously, onclick will always fire when you double-click. So I tried using a timeout-based structure like this...
window.onload = function() {
var timer;
var el = document.getElementById('testButton');
el.onclick = function() {
timer = setTimeout(function() { alert('Single'); }, 150);
}
el.ondblclick = function() {
clearTimeout(timer);
alert('Double');
}
}
But I got inconsistent results (using IE8). It would work properly alot of times, but sometimes I would get the "Single" alert two times.
Has anybody done this before? Is there a more effective way?
Like Matt, I had a much better experience when I increased the timeout value slightly. Also, to mitigate the problem of single click firing twice (which I was unable to reproduce with the higher timer anyway), I added a line to the single click handler:
el.onclick = function() {
if (timer) clearTimeout(timer);
timer = setTimeout(function() { alert('Single'); }, 250);
}
This way, if click is already set to fire, it will clear itself to avoid duplicate 'Single' alerts.
If you're getting 2 alerts, it would seem your threshold for detecing a double click is too small. Try increasing 150 to 300ms.
Also - I'm not sure that you are guaranteed the order in which click and dblclick are fired. So, when your dblclick gets fired, it clears out the first click event, but if it fires before the second 'click' event, this second event will still fire on its own, and you'll end up with both a double click event firing and a single click event firing.
I see two possible solutions to this potential problem:
1) Set another timeout for actually firing the double-click event. Mark in your code that the double click event is about to fire. Then, when the 2nd 'single click' event fires, it can check on this state, and say "oops, dbl click pending, so I'll do nothing"
2) The second option is to swap your target functions out based on click events. It might look something like this:
window.onload = function() {
var timer;
var el = document.getElementById('testButton');
var firing = false;
var singleClick = function(){
alert('Single');
};
var doubleClick = function(){
alert('Double');
};
var firingFunc = singleClick;
el.onclick = function() {
// Detect the 2nd single click event, so we can stop it
if(firing)
return;
firing = true;
timer = setTimeout(function() {
firingFunc();
// Always revert back to singleClick firing function
firingFunc = singleClick;
firing = false;
}, 150);
}
el.ondblclick = function() {
firingFunc = doubleClick;
// Now, when the original timeout of your single click finishes,
// firingFunc will be pointing to your doubleClick handler
}
}
Basically what is happening here is you let the original timeout you set continue. It will always call firingFunc(); The only thing that changes is what firingFunc() is actually pointing to. Once the double click is detected, it sets it to doubleClick. And then we always revert back to singleClick once the timeout expires.
We also have a "firing" variable in there so we know to intercept the 2nd single click event.
Another alternative is to ignore dblclick events entirely, and just detect it with the single clicks and the timer:
window.onload = function() {
var timer;
var el = document.getElementById('testButton');
var firing = false;
var singleClick = function(){
alert('Single');
};
var doubleClick = function(){
alert('Double');
};
var firingFunc = singleClick;
el.onclick = function() {
// Detect the 2nd single click event, so we can set it to doubleClick
if(firing){
firingFunc = doubleClick;
return;
}
firing = true;
timer = setTimeout(function() {
firingFunc();
// Always revert back to singleClick firing function
firingFunc = singleClick;
firing = false;
}, 150);
}
}
This is untested :)
Simple:
obj.onclick=function(e){
if(obj.timerID){
clearTimeout(obj.timerID);
obj.timerID=null;
console.log("double")
}
else{
obj.timerID=setTimeout(function(){
obj.timerID=null;
console.log("single")
},250)}
}//onclick
Small fix
if(typeof dbtimer != "undefined"){
dbclearTimeout(timer);
timer = undefined;
//double click
}else{
dbtimer = setTimeout(function() {
dbtimer = undefined;
//single click
}, 250);
}
, cellclick :
function(){
setTimeout(function(){
if (this.dblclickchk) return;
setTimeout(function(){
click event......
},100);
},500);
}
, celldblclick :
function(){
setTimeout(function(){
this.dblclickchk = true;
setTimeout(function(){
dblclick event.....
},100);
setTimeout(function(){
this.dblclickchk = false;
},3000);
},1);
}
I found by accident that this works (it's a case with Bing Maps):
pushpin.clickTimer = -1;
Microsoft.Maps.Events.addHandler(pushpin, 'click', (pushpin) {
return function () {
if (pushpin.clickTimer == -1) {
pushpin.clickTimer = setTimeout((function (pushpin) {
return function () {
alert('Single Clic!');
pushpin.clickTimer = -1;
// single click handle code here
}
}(pushpin)), 300);
}
}
}(pushpin)));
Microsoft.Maps.Events.addHandler(pushpin, 'dblclick', (function (pushpin) {
return function () {
alert('Double Click!');
clearTimeout(pushpin.clickTimer);
pushpin.clickTimer = -1;
// double click handle here
}
}(pushpin)));
It looks like the click event masks the dblclick event, and this usage is clearing it when we add a timeout. So, hopefully, this will work also with non Bing Maps cases, after a slight adaptation, but I didn't try it.

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