I'm working on a project where there's quite a lot of jQuery going on. So when I go to the page, I can see the jQuery running (e.g. $.button() elements on the page still appear as normal html elements before jQueryUI is loaded :S) so initially it looks all ugly THEN, once all the JS is loaded and executed, it looks "nice".
It's not just a case of preloading images or whatever, I want to RUN the jQuery code, but "hide" it from visitors so that once the page is opened, it looks "nice" straight away OR displays a black screen saying "Loading..." until the jQuery has finished running.
Take a look here: http://www.filamentgroup.com/ , though I'm not sure that actually runs the site's javascript before displaying it, but it shows the basic idea of having a dark screen saying "Loading...".. I suspect that's what happens in large web apps such as SlideRocket though it does use flash... :S
You answered the question yourself. Have some kind of loading screen that hides the page until all of the jQuery is run.
Try something like the following.
This goes at the top of your page:
<div id="loadingMask" style="width: 100%; height: 100%; position: fixed; background: #fff;">Loading...</div>
Here's your jQuery:
$(document).ready( function() {
/*
* ... all of your jQuery ...
*/
// At the bottom of your jQuery code, put this:
$('#loadingMask').fadeOut();
});
Wrap all of your jQuery that you want "preloaded" into this :
$(window).load(function() {
//Your jQuery here
});
or alternatively, not all of your jQuery code inside of that wrapper. Rather, put your jQuery DOM changes into a
$(document).ready(function(){
//jQuery
}))
and then have a wrapper for all your site content.
<div id="everything-wrapper">
<!-- put your body here -->
</div>
and set the display to none in your CSS
#everything-wrapper {
display : none;
}
and then with the window load like earlier
$(window).load(function() {
$("#everything-wrapper").show();
// or
$("#everything-wrapper").fadeIn("fast");
// to be fancy with it
});
I was having a similar issue with an artifact popping up briefly during page loads in IE8. The solution I used was to change the visibility of the container to hidden at line 1 of the css. Then showed the element at the end of the jquery file. If the css and jquery start arguing, the element isn't shown until the argument is resolved.
I would have a overlay as part of your static CSS and HTML, then when JQuery loads via
$(document).ready() you can hide the overlay
The answer by Christopher is most likely the way FilamentGroup do it. You can have javascript "preloaded", it loads inline with the rest of the page, and due to it usually being larger than the rest of the page takes longer to download. You can't make javascript load first, that's not the way it works.
However, the principle to make it work is to "hide" your page from view in CSS (or with inline styles as the CSS will still have to load) then once everything is ready in javascript show it all again. If you notice there is a gap between the page displaying (nothing) and the javascript loading showing on FilamentGroup. That is because they hide the page, the javascript loader loads, then once the rest of the javascript has finished it hides the loader and shows the page.
Dude, I did you up a sample. I hope you likes. I use something like this on my own site.
http://jsfiddle.net/jMVVf/
Related
I am writing a free online e-book which needs a few minor formatting tweaks:
http://rperl.org/learning_rperl.html
The "Full Table Of Contents" at the very top of the page starts out by being visible for a few seconds, then finally collapses itself to be hidden. What we need is for it to start as hidden, and not be visible at all for the several seconds while the page loads. You can see that I have already tried to solve this issue by setting "var index_hidden=1;" at the following link, otherwise the table of contents would never hide itself at all:
https://github.com/wbraswell/rperl/blob/gh-pages/javascripts/metacpan_rperl.js#L832-L833
It probably shouldn't matter, but I'm using some custom Perl scripts to generate this file from Perl POD source, I can give more info if needed.
Although the described behavior does not appear for me (OSX + Firefox). Here's what you might do:
Hide the element by default using CSS. Add this to your head element (extend with stronger hiding CSS when needed).
<style>.wait-for-js { display: none; }</style>
And hide your element by adding the class
<div id="index-container" class="hide-index wait-for-js">
Last but not least, to make this trick functional. Remove the class as soon as JS is loaded, which would also mean that other logic has been loaded and you're save to show the table of contents. Be sure to load this JavaScript last thing you'll do.
<script>
document.getElementById('index-container').className = 'hide-index';
</script>
Or if you're using jQuery
<script>$('.wait-for-js').removeClass('wait-for-js');</script>
Welcome to SO!
I'm using Skrollr to animate & create parralax effects when scrolling the page, but there's a short lag which I guess is the Skrollr javascript/jQuery initialising.
Any ideas on how to avoid having the mess at the beginning?
The WP website in question is this one : http://hustynminepark.com
Thank You!
Unless I'm mistaken, the layout of your page entirely depends on the activation of the plugin. You can solve this problem by finetuning the CSS so that the initial page corresponds exactly to what you see after activation of the plugin.
Also, don't forget to minify (concatenate / uglify) your javascript files before loading them into the browser; this will speed up the loading of the page and the activation of the plugin.
Btw, the site looks pretty cool.
If I am correct you have a FOUC, you can use jQuery to detect when your DOM in ready then call init.
First of all you want to include the skrollr.min.js file at the bottom of your document (right before the closing ) and then call skrollr.init(). Or you can place it inside the if you want to, but make sure to call init() once the document has been loaded (e.g. jQuery's ready event or even window.onload).
I want to prevent an specific background-image being displayed on a page, possibly using jquery. However, the page and DOM is loaded before the JS is activated.
What I want to do is the following:
.pagelayout-login #page{
background: none;
}
I have tried the same in JQuery using:
$(document).ready(function(){
$(".pagelayout-login #page").css("background","none");
});
However, both modify the stylesheet after the image has been loaded and displayed.
If I add "run_at : "document_start" inside my content scripts, the CSS get's overridden by the page's CSS.
Is there a way to prevent the background from being displayed before it starts loading?
you can add the CSS at the beginning :
chrome.tabs.insertCSS(tab.id, {code:'my css code', allFrames:false, runAt:"document_start"});
or add a script at the end like this :
chrome.tabs.executeScript(tab.id, {code:'my script code', allFrames:false, runAt:"document_end"});
with the CSS, you need to be the first, because it's a "Cascading Style".
with the script, it must be the last change.
You can try to add !important to your CSS.
I'd think this would be a lot easier the moment you remove the $(document).ready, everything inside that function runs after the page has completed loading.
Since this is in a Chrome extension, don't be afraid to use !important to ensure that your CSS overrides the page's CSS even if you "run_at : "document_start":
.pagelayout-login #page{
background: none !important;
}
This may or may not prevent the image from loading since it's still being referenced by the page's CSS, but it will at least prevent it from displaying right away. You will need to conduct your own tests to determine if Chrome will still attempt to request the image during page load in spite of this.
I have done a bit of a web development faux pas by not starting with a functioning page and then building js functionality on top. The site I am redeveloping is an old site which has lots of pretty jquery animations.
I have gone to great trouble to ensure all page loads can be handled with or without ajax but I have just realised this is entirely pointless since the initial page load produces several elements which load with properties of display:none; or opacity:0; and are animated to be visible on doc ready
I would very much like to rectify this but there are several reasons I did it in the first place:
1: to hide a flash of unstyled menu before a jquery plugin kicks in. (I will replace this with a non js menu and animate into the jquery menu to solve this)
2: The other reason is that I like the initial animation on page load and would ideally like to keep it. But this presents a problem since I would like to have the bulk of the page invisible for js users and visible for non js users on load but how can I ensure that my elements css properties are changed BEFORE the page is rendered - I have tried doing this with jquery but by the time the jquery library has loaded (without caching) my page has already rendered so the content is flashed up before being hidden and animated back in?
This block will be visible only for users with JS turned off.
<noscript>html code here</noscript>
You can add some styles like this:
<noscript>
<style>
#content{
background: red;
}
</style>
</noscript>
You can add the following in your <head>:
<script>document.documentElement.className+='js'</script>
Then you can style javascript-enabled browsers differently using the js class on the html element, f.ex:
html .animate{opacity:1} /* all browsers */
html.js .animate{opacity:0} /* js-enabled browsers */
The class is added already in the head, so there is no flicker in the rest of the DOM.
You can also use the noscript tag, but personally I think this is cleaner because you can administrate the styles in a single stylesheet.
on loading a page I have some javascript code which hides some layers
document.getElementById(layerName).style.display = "none";
Everything works well, but in IE and in Opera these DIVs are showing up for the first few milliseconds while the page loads. After that, it's back to normal.
Is there a way around that?
Thanks!
If you run code when the page loads, it will not run until the page finishes loading.
Instead, you can put the code in a <script> block below the elements, without handling onload.
Or you just use CSS.
you could set display to false in you HTML code
Is there a way around that?
It's called CSS:
.layer {
display:'none';
}
This problem occurs because of the way the browser renders the page. CSS is first before Javascript. So always try to do things in CSS when possible.
place this script immediately below the div placed. you will almost clear the problem