I have a application that loads CSS styles dynamic based on user preference. I use requirejs to load these like:
require(['css!dir/styles'], function(){ .... });
this works great but I don't want to show the screen until all the styles have fully initialized.
I've added a CSS class to the body of the page called hide-page and then remove that class when the callback occurs. Like:
setTimeout(function() { $(document.body).removeClass('hide-page'); }, 100);
but even with the settimeout, the page still loads jumbled until everything has initialized. I was thinking about doing a setInterval and checking if a particular style has been applied to a node like:
setInterval(function(){
if($(document.body).style('background'') === "#FFFFFF"){
$(document.body).removeClass('hide-page');
}
}, 10);
but thats kinda hackey. Is there a better solution anyone has to accomplish this?
You don't say how you're hiding the page content, but that could be the problem if you're using display:none.
Try visibility:hidden instead. This will allow the browser to allocate the space needed to construct the page, so you shouldn't see the jumbled FOUC.
Related
Is there a way to remove all styling from an Electron webview before the page is shown?
So far, I can inject JS to remove all styling after the document is loaded:
document.addEventListener("DOMContentLoaded", function(){
document.querySelectorAll('link[rel="stylesheet"], style').forEach(elem => elem.disabled = true);
});
The problem here is that the styles will show for a brief moment (~1 second) before styling is removed.
I can also use the following in my Main class to remove all .css files prior to page load:
session.webRequest.onBeforeRequest({urls: ['https://*/*.css', 'http://*/*.css']}, function(details, callback) {
callback({cancel: true});
});
This, however, does not remove tags embedded in the DOM. For a better idea of what I'm trying to do, you can check out Firefox's "No Style" feature (View -> Page Style -> No Style).
Thanks in advance.
There are two ways I can think of to prevent this:
Give the webview a visibility:hidden style, and make it visible later.
Point to a forwarding proxy who will strip out inline as well as linked CSS
Number 1 sounds to me a quicker and more reliable solution, but I haven’t tried it out.
Let me know how it goes.
I've created this code to print data from an iFrame
function (data) {
var frame = $("<iframe>", {
name: "iFrame",
class: "printFrame"
});
frame.appendTo("body");
var head = $("<head></head>");
_.each($("head link[rel=stylesheet]"), function (link) {
var csslink = $("<link/>", { rel: "stylesheet", href: $(link).prop("href") })
head.append(csslink);
;});
frame.contents().find("head")
.replaceWith(head);
frame.contents().find("body")
.append(this.html());
window.frames["iFrame"].focus();
window.frames["iFrame"].print();
}
This creates an iFrame, adds a head to where it sets all the css links that are needed for this website. Then it creates the body.
Trouble is, the styling won't get applied to the print, unless I break at line frame.contents().find("head").replaceWith(head), which means that something in that part is running asynchronously.
Question is, can I somehow get the code to wait for a short while before running that line, or is there perhaps another way to do this? Unfortunately I'm not all that familiar with iFrames, so I have no clue what it's trying to do there.
This turned out to be a real hassle. I've always been reluctant to using iframes, but since there are many resources saying that using an iframe for printing more stuff than what's on the screen, we figured we'd give it a try.
This was instead solved by putting the data inside a hidden div which then was shown before a window.print(). At the same time, all other elements on the page were given a "hidden-print" class which is a class we're already using to hide elements for prints.
This might not be as elegant for the user (The div will show briefly before the user exits the print dialogue), but it's a way more simpler code to use and manage.
I think you could / should move the last focus() and print() calls to a onload handler for the iframe, to get it to happen after styles are loaded and applied.
I've just run into the same issue and did the following:
setTimeout(() => {
window.frames["iFrame"].focus();
window.frames["iFrame"].print();
}, 500)
This appears to have sorted it for me. I hate using timeout and the length is guess work at best but as it's not system critical it's something I can run with for now.
I have a need to add a class to certain pages - ones that contain an ID of #hero. For all other pages, the class must not be added.
Because I'm using asp.net with a few layered master pages, its not as simple as just adding a class directly to the html becuase the body tag sits a couple of pages above the aspx page.
I could locate the body tag, but so far I've tried to avoid that due to the added complexity, and instead tried to use jquery.
Here's the code:
$(document).ready(function () {
updateBodyClasses();
});
function updateBodyClasses() {
if($("#hero")) {
$("html, body").addClass("hero");
}
}
Nothing complicated, but here's the rub. By the time the class has been appended, the page has been rendered and the class doesn't seem to have any effect. However, if I test it by adding the class directly to the html, it works - so I know the CSS works and that its a timing issue.
I suppose I could add the code higher up the page - jquery is deferred, so I would need to know the equivalent javascript to try it out.
Would appreciate any thoughts on this potential solution, or perhaps and other ideas.
/* UPDATE */
For clarity, it seems to be the HTML related class that isn't being applied.
You can alter the DOM without waiting for it to be ready.
You need to:
load jQuery in a synchronous way(without defer or async).
Put #hero element i above the script.
Please consider this example:
.red {
color: red;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id="hero">I don't care about DOM being ready</div>
<script>
var $el = $('#hero');
if ($el.length) {
$el.addClass('red');
}
</script>
You can use IIFE(Immidiately Invocked Function Expression):
like:
(function()
{
if($("#hero")) {
$("html, body").addClass("hero");
}
})();
just put your function in document ready like
$(function(){
if($("#hero")) {
$("html, body").addClass("hero");
}
});
No real solution provided.
Not reasitic to change the whole site infrastructure - from one that defers jquery to loading it synchronously.
The two other jquery answers are as per the current setup and don't work.
The only working solution was provided by Tushar, although it would still require selective loading of the script, which was not included in the answer.
In the end, I used a workaround, which bypassed the need for any javascript. Instead of selectively adding a class to html tag, I added the css permanently to the html tag, affecting all pages. I then added an inner div, which reverses it out. This means that any page can now manipulate its own functionality directly without having to add classes to the html tag.
I'm working to use custom checkbox styles with a checkbox which is dynamically generated by javascript for the Google Identity Toolkit. For example, we add this div:
<div id="gitkitWidgetDiv"></div>
And the Google Identity Toolkit script generates new html for that div.
I need to add a class to the HTML which is added by the javascript without any action by the user and I'm struggling to make it work. For example, here is my code:
$("#gitkitWidgetDiv").on('ready', ".gitkit-sign-in-options label", function() {
$(this).addClass('checkbox');
});
I've tried switching 'ready' for a few other options and also using the livequery plugin, but nothing is working for me. It works if I use an active event like 'click,' but I can't figure out how to do this when the page loads. Could someone please help? Thanks!
Modern browsers (including IE11) support mutation obervers. You can use one to monitor the parent node of the div that will be added. When the div has been added, just add the class.
Here's something I made which comes in handy in annoying cases like this where it's difficult to tell when the element you need has finished loading in: https://gist.github.com/DanWebb/8b688b31492632b38aea
so after including the function it'd be something like:
var interval = 500,
stopTime = 5000,
loaded = false;
setIntervalTimeout(function() {
if($('.dynanicElementClass').length && !loaded) {
$('.dynanicElementClass').addClass('checkbox');
loaded = true;
}
}, interval, stopTime);
It's not perfect and I'm sure there are better solutions out there but in most cases like this it does the job.
I am using some JS code to transform my menu into a drilldown menu.
The problem is before it runs the JS you see a BIG UGLY mess of links. On their site its solved by putting the js at the top. Using recommendations by yahoo/YSlow i am keeping the JS files at the bottom.
I tried hiding the menu with display:none then using jquery to .show(), .css('display', ''), .css('display', 'block') and they all lead up to a messsed up looking menu (i get the title but not the title background color or any links of the menu)
How do i properly hide a div/menu and show it after being rendered?
In the <head> place this:
<script>document.documentElement.className = 'js';</script>
Now, it will .js class to your html element. And it will be the very first thing done by the javascript on the page.
In your CSS you can write:
.js #menu {
display:none;
}
And then:
$(document).ready(function() {
$('#menu').css('display','block').fancyMenu();
});
This is an excellent technique, that allows you to make your pages "progressively enhanced", if your user has JavaScript disabled – she will still be able to see the content, and you can also separate non-JS styling with styling, that is relevant only for JS version of your menu, perhaps "position:absolute" and things like that.
At the top of your page put:
<script type="text/javascript">
document.write('<style type="text/css">');
document.write('#mylinks { display:none; }');
document.write('</style>');
</script>
And at the end of your "processing", call $('#mylinks').show();
document.write is evaluated as the DOM is processed, which means this dynamic style block will be registered in the style rules before the page is first displayed in the viewport.
This is a good case where progressive enhancement works really well - if your users have JS available & enabled, you hide the links until they are ready; but if not, they are still available, albeit ugly.
Life will be gentler with you if you try not to make pages that look like "a big ugly mess" without javascript. Have a heart.
Whatever yahoo says, it would probably be worth it for you to insert a little script that adds a style element with a few rules to the head of ypur document, before the body renders.
I found the solution. I should let the links be hidden with css then .show() BEFORE the ddMenu code executes instead of after. The ddMenu seems to check the parents width and sinces its hidden i guess its 0. The time between .show() and ddMenu is fast enough not to show the ugly links (on my machine/browser). The the majority of the time (page loading, http req for the JS files, JS compiling/exec etc) the links are hidden so it looks pretty good.
$(function () {
$('.menuT1').show(); //do it before not after in this case.
$('.menuT1 > ul').ddMenu({
Well, If you are familiar with jquery then I would do something like this
$("#mybuttom").click(function() {
$("#mydiv").hide(); //hide the div at the start of process
$.post( "mypostpage.php",
{ testvar: testdata },
function(data) {
//callback function after successful post
$('#mydiv').show(); //show it again
}
);
});