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Start javascript after lazy load images

I have a problem with a javascript. The script causes three elements on my website to be the same size. I would like to load my pictures by lazy load. This makes the rendering incorrect because the size of the elements is calculated by the script without the images. Is it possible to give the javascript a function that it will start only after the images have been loaded successfully by lazy load?
<script type="text/javascript">
jQuery(document).ready(function($){
function kb_equal_height() {
var highest_element = 0;
// Delete the height
$('.navigation-left,.site-content,.widget-area').each(function() {
$(this).removeAttr('style');
});
// Check which element is highest
$('.navigation-left,.site-content,.widget-area').each(function() {
if ($(this).height() > highest_element) {
highest_element = $(this).height();
}
});
// Assign this height to all elements
$('.navigation-left,.site-content,.widget-area').each(function() {
$(this).height(highest_element);
});
};
window.onload = kb_equal_height;
var resizeTimer;
$(window).resize(function() {
clearTimeout(resizeTimer);
resizeTimer = setTimeout(kb_equal_height, 100);
});
});
</script>

You can use image.onload to call the function when the image finished to load
You might not really see it in action here as the images probably won't take long enough to load for you to see intermediate state but it works
you'll need to clean your cache if you want to see it in action a second time as your browser will load the images from cache the second, third... times
let nbCat = 0
let div = document.getElementById("nbImg")
Array.from(document.getElementsByClassName("doAction")).forEach(img => {
img.onload = imgLoaded // your function here
})
function imgLoaded(e) {
nbCat++
div.textContent = nbCat + " cat" + (nbCat > 1? "s":"") + " loaded"
}
img {
max-height: 50vh
}
<img class="doAction" src="https://r.hswstatic.com/w_907/gif/tesla-cat.jpg">
<img class="doAction" src="https://upload.wikimedia.org/wikipedia/commons/thumb/3/3a/Cat03.jpg/1200px-Cat03.jpg">
<img class="doAction" src="https://pre00.deviantart.net/5d96/th/pre/f/2012/103/d/d/dd0d35acf8ea1817dffe7677f018b5a4-d4vzsbg.jpg">
<img class="doAction" src="https://pre00.deviantart.net/758d/th/pre/f/2018/006/2/7/tigerfieldadjusted_by_mssylviarose-dbz65qt.jpg">
<div id="nbImg">no cat loaded</div>

Execute js after all image loaded not working

(not duplicate, because not find exactly/easy solution)
I'm trying to execute JS after all images completely loaded. My goal is, when all images finish load completely, then removeClass my-loader and addClass visible to main-slider div.
HTML:
<div class='main-slider my-loader'>
<img src="https://unsplash.it/200/300/">
<img src="https://unsplash.it/200/300/">
<img src="https://unsplash.it/200/300/">
</div>
Execute below js when all images completely loaded
$(".main-slider").removeClass("my-loader").addClass("visible");
Tried this js :
But not works properly on my site, problem is when i clear browser cache, then it works/execute! when i reload page then next time it's not works/execute! It only works when i clear browser cache.
var img = $('.main-slider img')
var count = 0
img.each(function(){
$(this).load(function(){
count = count + 1
if(count === img.length) {
$('.main-slider').removeClass('my-loader').addClass('visible')
}
});
});
Any simple solution? Thanks in advance.

jQuery provides a way to register a callback for the window load event which will fire when the entire page, including images and iframes, are loaded.
Reference: https://learn.jquery.com/using-jquery-core/document-ready/
Your code should look something like:
$( window ).load(function () {
var img = $('.main-slider img')
var count = 0
img.each(function(){
$(this).load(function(){
count = count + 1
if(count === img.length) {
$('.main-slider').removeClass('my-loader').addClass('visible')
}
});
});
});

Here's how to do this, using Deferreds and native handlers, and calling the onload handler if the image is cached in older browsers etc.
var img = $('.main-slider img');
var defs = img.map(function(){
var def = new Deferred();
this.onload = def.resolve;
this.onerror = def.reject;
if (this.complete) this.onload();
return def.promise();
});
$.when.apply($, defs).then(function() {
$('.main-slider').removeClass('my-loader').addClass('visible')
});

jQuery document ready buggyness with social sharing services

I have a strange issue that might have to do with jQuery document ready. Below is an html and script block that contains the usual social networking scripts. The Javascript block below displays the dd_outer div on the left edge of the body div, and when the browser window is shrunk, the div is faded out and the dd_footer div is faded in. The fadein and fadeout between the two divs works OK.
The problem is two fold: one issue is when the browser window is full width (1200px+), the Facebook script will not load and display consistently; it sometimes appears and sometimes doesn't, sometimes after a page reload and sometimes doesn't. (No browser or .htaccess caching is involved). Only the Facebook share fails to show consistently; all other services show OK.
The second problem that when the browser window is narrow - 650 px or so, when the dd_outer div is not displayed and the dd_footer div is - the footer div will not show on a page reload until the browser window is moved the smallest amount. Then the the div will display, Facebook share and all. For a mobile device, this is a problem because the browser window will be narrow to begin with and shouldn't need to be "nudged" to make the dd_footer div display.
This problem may have come into play because I have adapted this code from a WordPress plugin that used options to set the position of the dd_outer div and scroll height. That's the reason for the variables above the document ready call.
Is this the issue with what seems to be a document ready issue?
How can the variables be integrated into the script itself? It doesn't matter if they are hardcoded; I can change them when needed.
I'd throw this in a jsfiddle to demo but the divs won't realistically float with the window resizing.
I haven't included the CSS for clarity.
This is the html and social script block:
<div class='dd_outer'><div class='dd_inner'><div id='dd_ajax_float'>
<div class="sbutton"><script src="http://connect.facebook.net/en_US/all.js#xfbml=1"></script><fb:like layout="box_count" show_faces="false" font=""></fb:like></div>
<div class="sbutton">
Tweet<script type="text/javascript" src="http://platform.twitter.com/widgets.js"></script></div>
<div class="sbutton"><script type="text/javascript" src="https://apis.google.com/js/plusone.js"></script><g:plusone size="tall"></g:plusone></div>
<div class="sbutton"><script src="http://platform.linkedin.com/in.js" type="text/javascript"></script>
<script type="IN/Share" data-counter="top"></script></div>
</div></div></div>
In the footer is <div id="dd_footer">that contains the same social scripts as above</div> and are faded in and out by the script below:
This is the jQuery that positions the dd_outer social services to the left and fades it out and fades in the dd_footer div.
<script type="text/javascript">
var dd_top = 0;
var dd_left = 0;
var dd_offset_from_content = 70; var dd_top_offset_from_content = 10;
jQuery(document).ready(function(){
var $floating_bar = jQuery('#dd_ajax_float');
var $dd_start = jQuery('#dd_start');
var $dd_end = jQuery('#dd_end');
var $dd_outer = jQuery('.dd_outer');
// first, move the floating bar out of the content to avoid position: relative issues
$dd_outer.appendTo('body');
dd_top = parseInt($dd_start.offset().top) + dd_top_offset_from_content;
if($dd_end.length){
dd_end = parseInt($dd_end.offset().top);
}
dd_left = -(dd_offset_from_content + 55);
dd_adjust_inner_width();
dd_position_floating_bar(dd_top, dd_left);
$floating_bar.fadeIn('slow');
if($floating_bar.length > 0){
var pullX = $floating_bar.css('margin-left');
jQuery(window).scroll(function () {
var scroll_from_top = jQuery(window).scrollTop() + 30;
var is_fixed = $dd_outer.css('position') == 'fixed';
if($dd_end.length){
var dd_ajax_float_bottom = dd_end - ($floating_bar.height() + 30);
}
if($floating_bar.length > 0)
{
if(scroll_from_top > dd_ajax_float_bottom && $dd_end.length){
dd_position_floating_bar(dd_ajax_float_bottom, dd_left);
$dd_outer.css('position', 'absolute');
}
else if ( scroll_from_top > dd_top && !is_fixed )
{
dd_position_floating_bar(30, dd_left);
$dd_outer.css('position', 'fixed');
}
else if ( scroll_from_top < dd_top && is_fixed )
{
dd_position_floating_bar(dd_top, dd_left);
$dd_outer.css('position', 'absolute');
}
}
});
}
});
jQuery(window).resize(function() {
dd_adjust_inner_width();
});
var dd_is_hidden = false;
var dd_resize_timer;
function dd_adjust_inner_width() {
var $dd_inner = jQuery('.dd_inner');
var $dd_floating_bar = jQuery('#dd_ajax_float')
var width = parseInt(jQuery(window).width() - (jQuery('#dd_start').offset().left * 2));
$dd_inner.width(width);
var dd_should_be_hidden = (((jQuery(window).width() - width)/2) < -dd_left);
var dd_is_hidden = $dd_floating_bar.is(':hidden');
if(dd_should_be_hidden && !dd_is_hidden)
{
clearTimeout(dd_resize_timer);
dd_resize_timer = setTimeout(function(){ jQuery('#dd_ajax_float').fadeOut(); }, -dd_left);
jQuery('#dd_footer').fadeIn();
}
else if(!dd_should_be_hidden && dd_is_hidden)
{
clearTimeout(dd_resize_timer);
dd_resize_timer = setTimeout(function(){ jQuery('#dd_ajax_float').fadeIn(); }, -dd_left);
jQuery('#dd_footer').fadeOut();
}
}
function dd_position_floating_bar(top, left, position) {
var $floating_bar = jQuery('#dd_ajax_float');
if(top == undefined) top = 0 + dd_top_offset_from_content;;
if(left == undefined) left = 0;
if(position == undefined) position = 'absolute';
$floating_bar.css({
position: position,
top: top + 'px',
left: left + 'px'
});
}
</script>

jQuery .ready() does not wait for iframes and other external media to load. These social buttons tend to work by inserting an iframe. The load event does wait for iframes etc, so you could try using that event instead, i.e.
jQuery(window).load(function () {
/* put the code you had inside .ready() here */
});

The problem comes with your idea: $(document).ready() fires when the DOM is ready, not when all scripts are ready!
an idea would be to search for trigger of that social-APIs you are using or just delay your calculations (e.g. via setTimeout).
Keep in mind that they are asyncron, even if you specify "async" on the script-tag to be false, you still dont know when they will activate or are finished.

I suggest to use the standard DOM event window.onload if you want to make sure that all the external assets, scripts, images, etc. are loaded first before you do something:
window.onload = function () {
// your script that needs to run after all the external assets are loaded
}
Reference: https://developer.mozilla.org/en-US/docs/DOM/window.onload

I just ran into similar problems with the facebook script... I just used the integration in the HEAD-section with javascript and added an "asynchronous"-attribute to the javascript-embedding script which then fires an asynchronous "heeey, facebook is ready now, too"-event to my jQuery-eventqueue...
I can't help you in detail, because I don't totally understand what you WANT to do and would reorganize the whole code A LOT... so - contact me private (email/skype) or try figuring out... I used that lines of code: pastie.org/private/9m4b9eet1dzzkl6duqpkrg

Cycle through a list of html files with button

I have a list of products say:
laptops/prod1.html
laptops/prod2.html
laptops/prod3.html
monitors/prod1.html
monitors/prod2.html
monitors/prod3.html
I would like a button on my page that 'cycles' through the available items.
No idea how to do this. Is this possible with javascript?

function nextProduct(incr) {
var href = window.location.href
, offset = (typeof(incr)==='undefined' ? 1 : incr);
window.location = href.replace(/(\d+)\.html/, function(m, g1) {
return (Number(g1) + offset) + '.html'
});
}
Then you can do something like:
var button;
button = document.getElementByID('next-button');
button.addEventListener('click', function() { nextProduct(1); });
button = document.getElementByID('prev-button');
button.addEventListener('click', function() { nextProduct(-1); });

Setup a main page, this should not be a static html page but in your server side language of choice.
Include jquery to a main page using a script tag (you can get jquery from http://jquery.com/).
Your html could look like this:
<div id='content'></div>
<div>
<a href='javascript:void(0)' id='prev' class='btn'>Previous</a>
<a href='javascript:void(0)' id='next' class='btn'>Next</a>
</div>
In your js file you would have something like this:
var currPage = 0;
var pageList = ["laptops/prod1.html","laptops/prod2.html", "laptops/prod3.html"];
var totalPages = pageList.length;
$(".btn").on("click",function(){
//if we are at the last page set currpage = 0 else increment currPage.
currPage = currPage < (totalPages - 1) ? ++currPage : 0;
var page = pageList[currPage];
$('#content').load(currPage);
});
Some points to consider:
You will want to decide if the first page gets loaded on the main page load or on click
You will need to set a js variable to keep track of the currently loaded page
You will need to add some method of storing all the possible pages (think an array). This can get printed out to a script tag on the page on page load.
You need to decide what happens when you hit the end of the line. You can either cycle around or grey out the appropriate link.
jquery on
jquery load

Displaying the content of an external file within jQuery modal

I work with a simple modal to understand how jQuery modal works. With this process
var load = 'alert.html'; // THE PURPOSE OF THIS QUESTION IS TO CHANGE "alert.html" to "image.jpg"
$(this).click(function(e) {
e.preventDefault();
$('body').append('<div id="overlay" />');
$('#overlay').fadeIn(300, function() {
$('body').append('<div id="alertModalOuter"><div id="alertModal"></div></div>');
var outer = $('#alertModalOuter');
var modal = $('#alertModal');
var defWidth = outer.outerWidth();
var defHeight = outer.outerHeight();
modal.load(load + ' #alert', function() {
var alertBoxContent = $('#alert');
var alertWidth = alertBoxContent.outerWidth();
var alertHeight = alertBoxContent.outerHeight();
var widthCombine = -((defWidth + alertWidth) / 2);
var heightCombine = -((defHeight + alertHeight) / 2);
modal.animate({width: alertWidth, height: alertHeight}, 200);
outer.animate({marginLeft: widthCombine, marginTop: heightCombine}, 200, function() {
alertBoxContent.fadeIn(200, function() {
});
});
});
This appends the content of an external file come (from load) to the modal windows; but this only works for the content within tag of id="alert". How can I remove the role of "alert" to display the entire content of external file. For example, I want to load an external image (which is an image file and not between "alert" tag).

You don't have to specify the #alert selector and it'll load the whole page. It's worth noting that if you don't specify a selector, then load calls .html() and processes all the scripts before removing them. You may have some scripts running giving you unexpected results. The .load() docs