Develop Reference

jquery css applied but not visible for flex element

I find myself struggling to understand why my approach at recalculating width of an element on resize and seeing the result doesn't work.
Scenario:
I have a flex layout, with 3 unequally wide containers divided into 3/7, 1/7 and 3/7 of the width of the page. I use width: calc(100%/7) or width: calc(100%/7*3) to let the browser calculate the relation of these containers.
I am aware of the issue that Chrome rounds the calculated values down in case there is an inaccuracy when calculating the relation. This is visible when resizing the browser window as a subpixel-wide white stripe, where the background shines through between the containers on certain widths. Note: this problem does not happen in Firefox, they seem to round these values differently (?).
What I tried:
I used jQuery and parseFloat(document.getComputedStyle(element).width) to get the values of the containers and calculate the difference in order to "stretch" the middle container to fill in the gap:
jQuery(window).on('resize', function () {
var mainSite = document.getElementsByClassName('site-main')[0];
var leftStart = document.getElementsByClassName('page-trigger left')[0];
var middleStart = document.getElementsByClassName('page-trigger middle')[0];
var rightStart = document.getElementsByClassName('page-trigger right')[0];
var mainSiteWidth = parseFloat(window.getComputedStyle(mainSite).width);
var leftStartWidth = parseFloat(window.getComputedStyle(leftStart).width);
var middleStartWidth = parseFloat(window.getComputedStyle(middleStart).width);
var rightStartWidth = parseFloat(window.getComputedStyle(rightStart).width);
console.log(mainSiteWidth);
console.log(leftStartWidth);
console.log(middleStartWidth);
console.log(rightStartWidth);
var calculatedElementWidth = leftStartWidth + middleStartWidth + rightStartWidth
if (mainSiteWidth > calculatedElementWidth){
var diff = mainSiteWidth - calculatedElementWidth;
var newMiddleWidth = middleStartWidth + diff;
console.log("diff: " + diff);
console.log("new middle width: " + newMiddleWidth);
jQuery(middleStart).css({
flex : "0 0 " + newMiddleWidth + "px",
width: newMiddleWidth + "px",
minWidth: newMiddleWidth + "px",
maxWidth: newMiddleWidth + "px"
});
console.log(parseFloat(window.getComputedStyle(middleStart).width));
}
}).resize();
So far, the values get correctly calculated and even applied to the middleStart element, at least in the DOM inspector, however, the gap is still there, even though the css values indicate, it should have changed.
These were the css settings before the jquery modifications:
flex: 0 0 calc(100%/7); --> translates to 273.562px, Chrome shows as 273.56px
width: calc(100%/7); --> translates to 273.562px, Chrome shows as 273.56px
min-width: calc(100%/7); --> translates to 273.562px, Chrome shows as 273.56px
max-width: calc(100%/7); --> translates to 273.562px, Chrome shows as 273.56px
These are the values in the DOM inspector after that:
flex: 0 0 273.594px;
width: 273.594px;
min-width: 273.594px;
max-width: 273.594px;
I tried to create a jsfiddle but I couldn't reproduce that issue there, since my layout is more complex and has more layers.
Does anybody have an idea, why the css settings, though being applied to the element in the DOM, are not visible?
EDIT: this is what happens, try to resize the browser window horizontally (please ignore the occasional jump of the right element, I had to use float:left; to make it reproducable and it only happens in Chrome: jsfiddle

Render div content in fullhd then proportional scale

TV shows slides, that holds HTML inside. TV's resolution is FullHD (1920x1080).
When editing the slide I want to able to know, how slide will exactly be shown on TV. Although I have a FullHD monitor, I've never worked in the browser in fullscreen mode. Other people, which potentially be working with slides, want to see slides as is too.
Using another word, I need to render 1920x1080 div, then proportionally scale it to fit client's browser. How can be this done using CSS or JS, or jQuery?
Edit: I do NOT need to proportional manipulate the image. I need to see how page will look on FullHD resolution regardless of client's viewport resolution

UPDATED!! Here is the demo: https://jsfiddle.net/8jxk0atm/4/
Old resize 1920x1080 aspect ratio demo: https://jsfiddle.net/8jxk0atm/2/
You can create the div spec with 1920x1080. And put this
// screen zoom out for checking
document.body.style.zoom="40%"
on top of your js code.
It will zoom out your document so you can see what it will look on 1920x1080 div.
HTML
<div id="fullscreen"></div>
CSS
html,
body {
margin: 0;
padding: 0;
}
#fullscreen {
width: 1920px;
height: 1080px;
background: green;
color: #fff;
}
JS
// screen zoom out for checking
document.body.style.zoom="40%"
makeFullHD();
function makeFullHD() {
var value = $(window).outerWidth();
value *= 1;
var valueHeight = Math.round((value / 16) * 9);
$('#vidHeight').text(valueHeight);
$('#videoBox').css('width', value + 'px').css('height', valueHeight + 'px');
$('#videoPlayer').css('width', value + 'px');
$('#fullscreen').css({
width: value,
height: valueHeight
});
// test
$('#fullscreen').text('Width:' + value + '\n' + 'Height:' + valueHeight);
}
$(window).resize(function() {
makeFullHD();
});

Setting a CSS value as a javascript variable

Ok, I want to have a CSS value such as the value of width: 50%; to be a variable defined in pixels. Let's say that the 50% width is perhaps 1000px, or 500px. I want the javascript to detect the pixel value of the percent.
I have tried several times with absolutely no luck.

You can do it like below using jquery.
var width = $('#your_id').width();
Example
var width = $('#myDiv').width();
alert(width + 'px');
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div style="width: 200px;">
<div id="myDiv" style="width: 50%;"></div>
</div>

var total_width = $( window ).width();
var display_width = 50; //50%
var my_width_px = ((display_width * total_width) / 100); // 100 = 100%
This will may be helpful for you.

You can get the width in pixels using jQuery
var width = $('#mydivid').width();
Set the width of a div using jQuery
$("#mydivid").css("width", your_new_width);
Get width using javascript
document.getElementById("mydivid").offsetWidth;

Proportionally scale website to fit browser window

What would be an elegant solution to proportionally scale and center an entire website to fit a browser window (and updating as it's re-sized)
Assume the base layout is 720x500px
Content should proportionally scale to fit, and then re-center.
Essentially, operating like this Flash plugin: http://site-old.greensock.com/autofitarea/ (though base size is known)
Site will contain several different types of elements in that 720x500 area... ideal solution would just scale the whole thing, not needing to style each individual element (in case it matters- images will be SVG and so scaling should have no negative affect on resolution)

Depending on the browsers you need to support (IE9+), you could achieve that with simple CSS transform.
See an example (using jQuery) in this jsfiddle
var $win = $(window);
var $lay = $('#layout');
var baseSize = {
w: 720,
h: 500
}
function updateScale() {
var ww = $win.width();
var wh = $win.height();
var newScale = 1;
// compare ratios
if(ww/wh < baseSize.w/baseSize.h) { // tall ratio
newScale = ww / baseSize.w;
} else { // wide ratio
newScale = wh / baseSize.h;
}
$lay.css('transform', 'scale(' + newScale + ',' + newScale + ')');
console.log(newScale);
}
$(window).resize(updateScale);
If you need backwards compatibility, you could size everything in your site with % or em, and use a similar javascript to control the scale. I think that would be very laborious though.

One solution I'm using is working with a container in which I put an iframe that's being resized to fit as much available screen as possible without losing it's ratio. It works well but it's not completely flexible: you need to set dimensions in your content page in % if you want it to work. But if you can manage your page this way, I think it does pretty much what you want.
It goes like this. You create a container html page that's basically only styles, the resize script and the iframe call. And you content goes into the iframe page.
<style>
html, body
{
border: 0px;margin: 0px;
padding:0px;
}
iframe
{
display: block;
border: 0px;
margin: 0px auto;
padding:0px;
}
</style>
<script>
$(document).ready(function(e){
onResizeFn();
});
$(window).resize(function(e){
onResizeFn();
});
// this stretches the content iframe always either to max height or max width
function onResizeFn(){
var screen_ratio = 0.70 // this is your 720x500 ratio
if((window.innerHeight/window.innerWidth) > screen_ratio){
var theWidth = window.innerWidth
var theHeight = (window.innerWidth*screen_ratio);
} else {
var theHeight = window.innerHeight;
var theWidth = (window.innerHeight/screen_ratio);
}
document.getElementById("your_iframe").width = theWidth + "px"
document.getElementById("your_iframe").height = theHeight + "px"
}
</script>
// And then you call your page here
<iframe id='your_iframe' src='your_content_page' scrolling='no' frameborder='0'"></iframe>

JavaScript: Get window width minus scrollbar width

Ok, I thought this would be really simple, but it's turning out not to be. I think I'm just messing something up in my HTML/CSS, but here goes.
I have a basic page like so:
HTML
<!DOCTYPE html>
<html>
<head>
<link href='test2.css' rel="stylesheet" type="text/css" />
<script src="http://code.jquery.com/jquery-1.10.2.js"></script>
<script src="test2.js"></script>
</head>
<body>
<div id="scroll"></div>
</body>
</html>
test2.css
* {
padding: 0;
margin: 0;
}
html, body {
height: 100%;
width: 100%;
}
#scroll {
height: 100%;
width: 100%;
overflow: scroll;
background-color: black;
}
test2.js
$(document).ready(function() {
// my resolution is 1440x900
alert('innerwidth should be 1425');
// all of these return 1440
alert('body innerwidth: ' + $('body').innerWidth());
alert('document width: ' + $(document).width());
alert('window width: ' + $(window).width());
alert('scroll div innerwidth: ' + $('#scroll').innerWidth());
alert('document.documentElement.clientWidth: ' + document.documentElement.clientWidth);
alert('document.documentElement.scrollWidth: ' + document.documentElement.scrollWidth);
});
So I've got one element on the page... a div that takes up the entire screen, or rather it should be taking up the entire screen minus the scrollbars. Now, I've been doing some snooping on how to grab the width and height of a page without the scrollbars, but unfortunately, none of them return the proper value... which makes me believe I'm missing the boat in my HTML or CSS.
I looked at the following:
jquery - how to get screen width without scrollbar?
how to get the browser window size without the scroll bars
So what I need is for a method to return the value of my viewable screen minus the respective scrollbar value... so for my width, my value should be 1425 because the scrollbar is 15 pixels wide. I thought that's what innerWidth's job was, but apparently I'm wrong?
Can anyone provide any insight? (I'm running Firefox 24.)
EDIT
To add some background, I've got a blank page. I will be adding elements one by one to this page, and I need to use the width of the page when calculating the sizes for these elements. Eventually, this page will grow and grow until the scrollbar appears, which is why I'm trying to force the scrollbar there from the start, but apparently, that still doesn't do anything.
EDIT2
Here's something even more interesting... if I do document.getElementById('scroll').clientWidth, I get the proper innerWidth, but if I do $('#scroll').width() or $('#scroll').innerWidth(), they both return the max resolution... sounds like a jQuery bug.

I got this somewhere and would give credit if I knew where, but this has been succesfull for me. I added the result as padding when setting the html overflow to hidden.
Problem is that the scrollbar is a feature of the browser and not the web page self. Measurement should be done dynamically. A measurement with a scrollbar and a measurement without a scrollbar will resolve into calculating the difference in width.
Found the source: http://www.fleegix.org/articles/2006/05/30/getting-the-scrollbar-width-in-pixels
scrollCompensate = function () {
var inner = document.createElement('p');
inner.style.width = "100%";
inner.style.height = "200px";
var outer = document.createElement('div');
outer.style.position = "absolute";
outer.style.top = "0px";
outer.style.left = "0px";
outer.style.visibility = "hidden";
outer.style.width = "200px";
outer.style.height = "150px";
outer.style.overflow = "hidden";
outer.appendChild(inner);
document.body.appendChild(outer);
var w1 = inner.offsetWidth;
outer.style.overflow = 'scroll';
var w2 = inner.offsetWidth;
if (w1 == w2) w2 = outer.clientWidth;
document.body.removeChild(outer);
return (w1 - w2);
}
var htmlpadding = scrollCompensate();

The correct answer is in this post marked as accepted:
CSS media queries and JavaScript window width do not match
This is the correct code:
function viewport() {
var e = window, a = 'inner';
if (!('innerWidth' in window )) {
a = 'client';
e = document.documentElement || document.body;
}
return { width : e[ a+'Width' ] , height : e[ a+'Height' ] };
}

Discovered a very hacky solution... by adding this before my alerts in test2.js, I get the proper width:
var p = $('body').append('<p style="height: 100%; width: 100%;"></p>');
alert(p.width());
$('body').remove('p');
And consequently, all of the alerts now have the proper width. I also don't even need overflow-y in the CSS if I do it this way. Curious why this solves it...
The real answer should be keeping the HTML and CSS as is, then using document.getElementById('scroll').clientWidth. Using clientWidth gets the viewable area minus the scrollbar width.

The correct width of the page is given by $(document).width().
Your problem is that you're using a scroll within the div (overflow: scroll).
Using $(document).width() the returned value is already discounting the visible width of the scroll, but how do you put a scroll within the div value returned is no longer the same.
As the width of the scroll is not standard and varies from system to system and browser to browser, it is difficult to solve.
I suggest you remove the scroll of the div and let the browser manage this by default in the body, then yes you have the correct width.