like you see in the code below, the jquery loads a page but it seems that all the .css styling inside the jquery waits until the jquery is loaded which can take some fraction of a second if the file is big. So if I have .css("display","none") it will not work for that time causing a flickering before the styling kicks in. I have this problem only with Mozilla. The code below its only an example and it works well because is small. Some ideas how to fix this?
$(document).ready(function() {
$(".rectangle").click(function() {
$("body").load("debugging2.html", function() {
$(".rectangle").css("display","none")
$(".rectangle").fadeIn(1000);
}) ;
});
})
.rectangle{
height: 200px;
width: 200px;
background-color:#000;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<body>
<div>
<div class="rectangle"></div>
</div>
</body>
$(document).ready(function() {
$(".rectangle").click(function() {
$("head").append("<style>.rectangle{display:none;}</style>");
$("body").load("debugging2.html", function() {
$("rectangle").fadeIn(1000);
});
});
})
Since script tags are loaded synchronously (by default) they indeed block page rendering. It can result in blank unstyled page if HTML is not processed and styles are not loaded by that moment. Hence the common very simple solution is to move heavy script tags to the very end of the </body> and put necessary CSS style in the <head>.
As the result of above, CSS gets downloaded first, after HTML is loaded quickly, rendered and styled and only after that slow scripts get downloaded.
In code it will look something like this:
<head>
<link href="style.css" rel="text/css" type="stylesheet">
</head>
<body>
<div>
<div class="rectangle"></div>
</div>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<!-- some other scripts -->
</body>
As the bonus, you don't need to bind to document ready event anymore ($(document).ready(function() {});), since HTML is all loaded by default, when scripts are executed.
Thanks in advance for your help.
So I have a fully functioning page, but when I make the following changes, my jQuery accordion stops working on rollover and all of my navigation links (which point to #sections as it's a single-page scrolling site) stop working completely. Here is the deadly code:
<script type="text/javascript">
$(document).ready(function(){
$(document).ready(function () {
$('#fadeDiv').fadeIn(3000);
});
});
</script>
</head>
<body>
<DIV ID="fadeDiv" style="display:none;">
... page here ...
</div>
</body>
All functionality which breaks is WITHIN the fadeDiv. It's worth noting that the links (a href="#section") can be IN a div that fades in and will work fine, but will break if, rather, I fade in the containing div of #section.
Weird.
why are you calling the document ready 2?
Does the jquery file pulled in?
your code should look like this
<script type="text/javascript">
$(document).ready(function() {
$('#fadeDiv').fadeIn(3000);
});
</script>
and add this to your header
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js"></script>
and i would recomend putting the display none in css
It is possible not to show html page in user browser until some JavaScript(built-in or in separate file) will be loaded and executed(for page DOM manipulation)?
The easiest thing to do is to set the css variable
display: none;
to the whole page.
then when everything is loaded you can set the display to
display: block; // or something else that suits.
If you make sure that piece of CSS is loaded at the very start of your document it will be active before any html is shown.
if you use a javascript library like jQuery you'll have access to the $(document).ready() function, and can implement a switch over like this:
<html>
<head>
<title>test</title>
<style type="text/css">
body > div {
display: none;
}
</style>
<script type="text/javascript">
$(document).ready(function() {
$('body > div').css('display', 'block');
});
</head>
<body>
<div>
This will initially be hidden.
</div>
</body>
</html>
Not in the classical way you'd distribute a page. Browsers will (usually) start to display chunks of the base HTML file as it arrives.
Of course, you could simulate this by generating all the HTML on the fly from some included Javascript file. But that doesn't sound like a good plan as it will degrade horribly for people without JS enabled, or if you have a minor bug in your script. A better option might be to style the body tag to display: none and restyle it from the script to make certain parts visible again.
What is it you're actually trying to achieve? It sounds like there's likely to be a better way to do this...
Place the content of HTML page in a DIV, make its diplay none and on load of body diplay it.
<script type="text/javascript">
function showContent() {
var divBody=document.getElementById('divBody');
divBody.style.display= 'block';
}
</script>
<body onload="showContent()">
<div id="divBody" style="display: none;">
<--HTML of the page-->
</div>
</body>
Examples of what you might want to do:
Facebook's "BigPipe": http://www.facebook.com/notes/facebook-engineering/bigpipe-pipelining-web-pages-for-high-performance/389414033919
This method allows you to load JS first then ASYNC+inject all DOM content.
GMail
Zimbra (open-source web app similar to MS Outlook/Exchange)
My understanding is that you want to run some javascript code before you load the page. In the js file you write your init function and add the eventlistener to the window on "load" event. This will ensure that the init code gets executed first and then you can start displaying the HTML content.
var Yourdomain = {};
YourDomain.initPage = function(){
/* Your init code goes here*/
}
window.addEventListener("load", YourDomain.initPage, false);
All You really need to do is give your element an ID or CLASS and use the dislay: none; property. When your ready to show it just delete it.
CSS:
#div_1 {
display: none;
}
HTML:
<div id="div_1">
<p>This will be the hidden DIV element until you choose to display it.</p>
<p id="js_1"></p>
<script>
var x = "Some Test ";
var y = "Javascript";
document.getElementById("js_1").innerHTML = x + y;
</script>
</div>
Users in my site are seeing a half-second glitch on each page before any jQuery code executes. This code manipulates the page so you can visibly see elements move in one big chunk, making the user experience feel clunky. I'd prefer the page not to display at all until the JavaScript has run.
I'm using jQuery provided by the Google API in a page as follows:
<script type="text/javascript" src="http://www.google.com/jsapi"></script>
<script type="text/javascript">
google.load("jquery", "1.3.2");
</script>
<script type="text/javascript" src="MyScript.js"></script>
In MyScript.js:
google.setOnLoadCallback(runOnLoad);
function runOnLoad() {
// Do stuff
}
Does anyone know if it's possible to run the JavaScript before the page is displayed in the browser?
You could probably add a css class to your main div that would hide the content, and then remove that class as the last thing that MyScript.js does.
In your html template:
<body>
<div id="mainContent" class="hidden">
</div>
</body>
The css class:
.hidden
{
display: none;
}
Last executed statement of MyScript.js:
$("#mainContent").removeClass("hidden");
I would agree with Jan.
Most (not all) browsers load CSS first before javascripts.
So CSS would be advisable for you.
Is there a tag in HTML that will only display its content if JavaScript is enabled? I know <noscript> works the opposite way around, displaying its HTML content when JavaScript is turned off. But I would like to only display a form on a site if JavaScript is available, telling them why they can't use the form if they don't have it.
The only way I know how to do this is with the document.write(); method in a script tag, and it seems a bit messy for large amounts of HTML.
Easiest way I can think of:
<html>
<head>
<noscript><style> .jsonly { display: none } </style></noscript>
</head>
<body>
<p class="jsonly">You are a JavaScript User!</p>
</body>
</html>
No document.write, no scripts, pure CSS.
You could have an invisible div that gets shown via JavaScript when the page loads.
I don't really agree with all the answers here about embedding the HTML beforehand and hiding it with CSS until it is again shown with JS. Even w/o JavaScript enabled, that node still exists in the DOM. True, most browsers (even accessibility browsers) will ignore it, but it still exists and there may be odd times when that comes back to bite you.
My preferred method would be to use jQuery to generate the content. If it will be a lot of content, then you can save it as an HTML fragment (just the HTML you will want to show and none of the html, body, head, etc. tags) then use jQuery's ajax functions to load it into the full page.
test.html
<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script type="text/javascript" charset="utf-8">
$(document).ready(function() {
$.get('_test.html', function(html) {
$('p:first').after(html);
});
});
</script>
</head>
<body>
<p>This is content at the top of the page.</p>
<p>This is content at the bottom of the page.</p>
</body>
</html>
_test.html
<p>This is from an HTML fragment document</p>
result
<p>This is content at the top of the page.</p>
<p>This is from an HTML fragment document</p>
<p>This is content at the bottom of the page.</p>
First of all, always separate content, markup and behaviour!
Now, if you're using the jQuery library (you really should, it makes JavaScript a lot easier), the following code should do:
$(document).ready(function() {
$("body").addClass("js");
});
This will give you an additional class on the body when JS is enabled.
Now, in CSS, you can hide the area when the JS class is not available, and show the area when JS is available.
Alternatively, you can add no-js as the the default class to your body tag, and use this code:
$(document).ready(function() {
$("body").removeClass("no-js");
$("body").addClass("js");
});
Remember that it is still displayed if CSS is disabled.
I have a simple and flexible solution, somewhat similar to Will's (but with the added benefit of being valid html):
Give the body element a class of "jsOff". Remove (or replace) this with JavaScript. Have CSS to hide any elements with a class of "jsOnly" with a parent element with a class of "jsOff".
This means that if JavaScript is enabled, the "jsOff" class will be removed from the body. This will mean that elements with a class of "jsOnly" will not have a parent with a class of "jsOff" and so will not match the CSS selector that hides them, thus they will be shown.
If JavaScript is disabled, the "jsOff" class will not be removed from the body. Elements with "jsOnly" will have a parent with "jsOff" and so will match the CSS selector that hides them, thus they will be hidden.
Here's the code:
<html>
<head>
<!-- put this in a separate stylesheet -->
<style type="text/css">
.jsOff .jsOnly{
display:none;
}
</style>
</head>
<body class="jsOff">
<script type="text/javascript">
document.body.className = document.body.className.replace('jsOff','jsOn');
</script>
<noscript><p>Please enable JavaScript and then refresh the page.</p></noscript>
<p class="jsOnly">I am only shown if JS is enabled</p>
</body>
</html>
It's valid html. It is simple. It's flexible.
Just add the "jsOnly" class to any element that you want to only display when JS is enabled.
Please note that the JavaScript that removes the "jsOff" class should be executed as early as possible inside the body tag. It cannot be executed earlier, as the body tag will not be there yet. It should not be executed later as it will mean that elements with the "jsOnly" class may not be visible right away (as they will match the CSS selector that hides them until the "jsOff" class is removed from the body element).
This could also provide a mechanism for js-only styling (e.g. .jsOn .someClass{}) and no-js-only styling (e.g. .jsOff .someOtherClass{}). You could use it to provide an alternative to <noscript>:
.jsOn .noJsOnly{
display:none;
}
In the decade since this question was asked, the HIDDEN attribute was added to HTML. It allows one to directly hide elements without using CSS. As with CSS-based solutions, the element must be un-hidden by script:
<form hidden id=f>
Javascript is on, form is visible.<br>
<button>Click Me</button>
</form>
<script>
document.getElementById('f').hidden=false;
</script>
<noscript>
Javascript is off, but form is hidden, even when CSS is disabled.
</noscript>
You could also use Javascript to load content from another source file and output that. That may be a bit more black box-is than you're looking for though.
Here's an example for the hidden div way:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<style>
*[data-when-js-is-on] {
display: none;
}
</style>
<script>
document.getElementsByTagName("style")[0].textContent = "";
</script>
</head>
<body>
<div data-when-js-is-on>
JS is on.
</div>
</body>
</html>
(You'd probably have to tweak it for poor IE, but you get the idea.)
My solution
.css:
.js {
display: none;
}
.js:
$(document).ready(function() {
$(".js").css('display', 'inline');
$(".no-js").css('display', 'none');
});
.html:
<span class="js">Javascript is enabled</span>
<span class="no-js">Javascript is disabled</span>
Alex's article springs to mind here, however it's only applicable if you're using ASP.NET - it could be emulated in JavaScript however but again you'd have to use document.write();
You could set the visibility of a paragraph|div to 'hidden'.
Then in the 'onload' function, you could set the visibility to 'visible'.
Something like:
<body onload="javascript:document.getElementById(rec).style.visibility=visible">
<p style="visibility: visible" id="rec">This text to be hidden unless javascript available.</p>
There isn't a tag for that. You would need to use javascript to show the text.
Some people already suggested using JS to dynamically set CSS visible. You could also dynamically generate the text with document.getElementById(id).innerHTML = "My Content" or dynamically creating the nodes, but the CSS hack is probably the most straightforward to read.