is there a way with javascript/jquery to prevent images from loading? I am building a slideshow from a html list with images. So I would like to collect all the src data and then prevent the images from loading. So later when the user really needs the image I would load it then.
I found some lazy loading script on google but couldn't find the way they prevent images from loading.
Thanks in advance.
Edit1:
It seems from the answers that it's not possible to use javascript to prevent images from loading.
Here is a script that does lazy loading. Could anybody explain how it works? It seems when javascript is off it just loads the images normaly and when it's on it will load them when you scroll to their location.
You can wrap the image in a noscript tag:
<noscript>
<img src="foo.jpg"/>
</noscript>
All browsers that has JavaScript enabled will ignore the image tag so the image won't load.
If you render the HTML on the page, even if it's hidden, it's going to load. If you want images to load only when they're needed, you're going to have to dynamically set the source (src) on the image tag in javascript.
Edit 1: The script you referenced merely checks to see how far you've scrolled the page down and then determines which images are visible (or almost visible) by checking their top -- see the $.belowthefold and $.rightoffold extensions.
The example works great when the images are all the same size because their containers can also be the same size and you won't get any odd page resizing behavior when you lazy load them. If your images' heights and widths vary, you may get some odd results.
Edit 2:
<script type="text/javascript" charset="utf-8">
$(document).ready( function() { $("img").removeAttr("src"); } );
</script>
<img src="Chrysanthemum.jpg" />
<img src="Desert.jpg" />
<img src="Hydrangeas.jpg" />
<img src="Jellyfish.jpg" />
<img src="Koala.jpg" />
<img src="Lighthouse.jpg" />
<img src="Penguins.jpg" />
<img src="Tulips.jpg" />
Store the URLs somewhere else, then set all image URLs to some dummy image (empty, transparent, "loading data...", whatever). When an image should be displayed, use JS to set the src attribute and the browser will fetch it.
Well with Prototype you can do something like this I guess:
var unloaded = [];
$$('img.noload').each(function (image) {
unloaded.push(image);
image._src = image.src;
image.src = '';
});
To load all of them:
unloaded.each(function (image) {
image.src = image._src;
});
To load the first one:
function loadImage (image) {
image.src = image._src;
}
loadImage(unloaded.shift());
Well I hope you got the idea.
Just do not include the img tag in your original HTML, generate it on the fly using DHTML as you need it. You can also put a fake url to image in the img tag and replace it with the real one dynamically.
On the side note - what's the point. All you are trying to do here is to build another caching mechanism over the existing one. Leave caching to browsers, they are pretty good at this
You can use the portion below to replace all image tags with a dummy file (for example, an 1x1 transparent gif). The url's are stored in a array for later reference.
$(document).ready(function(){
var images = new Array();
$("img").each(function(i){
images[i] = this.src;
this.src='blank.gif';
});
});
I don't recommend this solution, for many reasons (like it ruins your page if you don't have Javascript enabled, screen-readers etc), but its a possibility...
You could change the IMG tag so that it hijacks a different attribute, like ALT (LONGDESC, or TITLE too):
Then use Javascript to update the SRC attribute with the ALT value as you need to.
So thats one way, and not a good one. I think the only real approach is to dynamically generate the proper IMG tag as needed via Javascript and not publish it with the HTML (this too has implications for non-JS browsers etc)
This article shows some tests using both css background and img tags on a set of standard browsers.
In my personal experience the PictureFill by Scott Jehl is the best solution I've ever used to deal with image resolutions and sizes for mobile devices.
I know this is an old question, but it took me a while to figure out how to accomplish what I wanted to. This is the top result on DuckDuckGo so I think it's worth posting here.
This little snippet will prevent imgs, embeds and iframes from being loaded and will manually load them later when needed.
One caveat: objects that are loaded too fast for JQuery/JavaScript to catch them are still loaded, and the script still removes them.
Since this is intended to decrease load time this should not be a problem though.
Fiddle
loadObjects = function() {
/* LOAD OBJECTS */
$("img, embed, iframe").each(function() {
var obj = $(this);
obj.attr("src", obj.data("objsrc")).ready(function() {
obj.fadeIn(1000, "linear").prev(".loading").fadeOut(750, "linear", function() {
$(this).remove();
});
});
});
}
$(document).ready(function() {
/* *** PREVENT OBJECTS FROM LOADING *** */
$("img, embed, iframe").each(function() {
var obj = $(this);
obj.data("objsrc", obj.attr("src"));
obj.hide().attr("src", "").before("<span class=\"loading\"></span>");
});
});
You can also wrap the image in a template tag:
<template>
<img src="foo.jpg"/>
</template>
Browsers will not try to load it.
The answer to this problem is very easy via insertAdjacentHTML() which lets you add HTML when you like, in this case on button click:
function LoadImages(){
document.body.insertAdjacentHTML('afterEnd','<img src="one.jpg" alt="" height="100" width="100"> <img src="two.jpg" alt="" height="100" width="100">');
}
The HTML...
<button onclick="LoadImages();">Click to load images</button>
I have included the page page loader script into my project with cakephp.I can see that it is loading as in body tag I can see the 'pace-running' and 'pace-done' class names.
As soon as I add this
$(function() {
Pace.on("done", function(){
alert('done');
// $("#pageToLoad").fadeIn(1000);
});
});
I get the alert and I can see that the div added from pace is active:
<div class="pace pace-active">
<div class="pace-progress" style="transform: translate3d(100%, 0px, 0px);" data-progress-text="100%" data-progress="99">
<div class="pace-progress-inner"></div>
</div>
<div class="pace-activity"></div>
</div>
which shoes me, everything is included well and works well.
But for some reason, I can't see the loading animation on my page.
I changed the z-index within the css template file of pace to '99999999' but the progress bar will not display :-(
There is a bug report regarding this. The recommended solution is:
$(document).ajaxStart(function() { Pace.restart(); });
I need something along these lines in one of my projects, but not in another, and I'm not sure what the difference is. :-(
I'm trying desperately to make the link on a linked image work but whenever I click on the link, my browsers (Chrome & Firefox) just tell me they are connecting to the page and I get a continuous spinning image as if the browser were doing something. The link works perfectly if I open in another tab.
The div in question is coded and styled in a Wordpress page. I am making changes to another developer's work for a customer.
Here's the div:
<div style="position: absolute; top: 645px; left: 80px; width: 150px;">
<a href="http://themoneycouple.com/?p=4681" target="_top" style="display:inline-block">
<img src="http://themoneycouple.com/wp-content/uploads/2013/10/kit-history.png" alt="Toolkit History Link" width="150" height="170" style="position:relative; display:block; z-index:999999999999;" />
</a>
</div>
And here's the page it's on: http://themoneycouple.com/resources/love-and-money-kit/
I've tried changing the z-index on every element in multiple ways, tried changing the link target in every way possible, changed display settings, etc.
One last note, there are lots of iframes on this page and I'm not sure if those are messing things up somehow. Massive thanks for any help.
It looks like the URL for that HREF is trying to load a page as a modal using the fancybox protocol. Is this what is expected?
Does that page ID exist? It looks URL looks different from the other page URLs on the site.
There is a jQuery function that targets every IMG tag w/ an A tag and applies a class of "fancybox". Modify the specificity of this function to exclude the last item in the gallery. Better yet, create a new class and add it to the elements that should have the fancybox functionality. The same issue happens on other pages where the HREF goes to a page instead of opening an image.
Current jQuery function:
var thumbnails = jQuery("a:has(img)").not(".nolightbox").filter( function() { return /\.(jpe?g|png|gif|bmp)$/i.test(jQuery(this).attr('href')) });
thumbnails.addClass("fancybox").attr("rel","fancybox").getTitle();
I think I found the link you mean and it has a fancybox class on it, so I presume it is trying to open a fancybox javascript plugin popout for your link.. which is a redirect and failing to do so, since I can right click the link and go to open in new tab and it works.
We have some embedded Spotify play buttons in a paged quiz style wizard/carousel (using jQuery Tools -yuk- to provide the paging functionality); the issue I'm having is that because each question is on a div that is initially hidden, the content of each Spotify iframe is unable to work out which player to render (small vs large).
It would be possible to force a refresh of these iframes when the user scrolls to each panel, but this feels like a hack and a bunch of extra HTTP requests.
Has anyone had any experience with this? Any workarounds that don't require me to multiply requests to Spotify?
Thanks in advance
S
The team in charge of the Spotify Play Button has recently released an update that fixes this issue. You don't need to make any change in your embed code.
Here I attach some sample code, together with its jsFiddle.
In example, being this the HTML:
<button id="show-play">Show Play Button</button>
<div id="container" style="display:none">
<iframe src="https://embed.spotify.com/?uri=spotify:track:4bz7uB4edifWKJXSDxwHcs" width="300" height="380" frameborder="0" allowtransparency="true">
</iframe>
</div>
you change its style CSS property:
(function() {
var button = document.getElementById('show-play'),
container = document.getElementById('container');
button.addEventListener(
'click',
function() {
container.style.display = 'block';
},
false
);
})();
You can see it in action in this jsFiddle.
Disclaimer: I'm a Spotify employee.
In my facebook iframe application, my home page is little long (about 1500px) but the secondary pages are smaller in height.
I see there is a lot of white space between my footer and the facebook's footer in the secondary pages.
I checked the iframe source and found the height property is set correctly, but there is another height value inside style tag which is retaining the homepage height.
<iframe class="canvas_iframe_util noresize" frameborder="0" scrolling="no" id="iframe_canvas" name="iframe_canvas" src='javascript:""' height="600px" style="height: 1566px; overflow-y: hidden; "></iframe>
Below is the code I am using to resize the frame (which is in the master page)
<script src="http://connect.facebook.net/en_US/all.js"></script>
<script>
FB.init({
appId: 'my app',
status: true, // check login status
cookie: true, // enable cookies to allow the server to access the session
xfbml: true// parse XFBML
});
FB.Canvas.setAutoResize(7);
</script>
My secondary pages are dynamic in size, so I can not use a fixed height.
Any help to get ride the extra white space on my secondary pages are highly appreciated.
Thanks
I did a Facebook Canvas App the other day and I wrote this little code to take care of the height issue.
<script>
FB.Canvas.setSize({ height: document.getElementById('wrapper').offsetHeight });
</script>
Of course this code demands a <div id="wrapper"></div> to wrap the whole page.
You have to make sure all the things in the DOM has loaded before you fire it tho. That's why I put it just before the </body>. But there can sometimes be a bit of a problem with images with unspecified height. So either you specify the height of all your images or you could fire it with the help of jQuery and document.ready().
You could/should switch to using FB.Canvas.setAutoGrow(), since FB.Canvas.setAutoResize() will be deprecated shortly.
Then set the canvas height option in the app settings to: Settable (Default: 800px)
In your app, you can use FB.Canvas.setAutoGrow() without any parameters. I know this is essentially what you're doing already, but in my experience this has served me well. This also solves any problems when the height of your page changes after the initial page load.