[javascript] 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?

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!

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();
}

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...
}

(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(){
    //...
});

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));

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.

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);
    });
});

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!
*/

ResizeStart and ResizeEnd events for window

http://jsfiddle.net/04fLy8t4/

I implemented function which trig two events on user DOM element:

1. resizestart
2. 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") );
};

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)

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.

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.

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);
});

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');
});

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);
}

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);

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;
}

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) );

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/

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);
});

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 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");

            }

}