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jQuery each() function not working after if/else statement has been completed for both if and else outputs

I am using jQuery & javascript to switch the classes for images based on whether the viewport width is less than or greater than twice the width of the image.
I am using $(window).resize to detect when the widow is resized and then the each() function to iterate through all images of a certain class.
An if statement checks whether the width of the viewport is less than twice the width of the image and if so removes one class and adds another. The else statement does the reverse.
One page load it works fine for as many widow width changes as I do, until both the if and the else have been executed, then they stop working. Any suggestions would be greatly appreciated!
Thanks
Here's my code:
function updateViewportDimensions() {
var w = window,
d = document,
e = d.documentElement,
g = d.getElementsByTagName("body")[0],
x = w.innerWidth || e.clientWidth || g.clientWidth,
y = w.innerHeight || e.clientHeight || g.clientHeight;
return { width: x, height: y };
};
jQuery(window).resize(function() {
var viewport = updateViewportDimensions();
var viewport_width = viewport['width'];
console.log('Viewport width = ' + viewport_width);
jQuery(document).ready(function($) {
$('.alignright').each(function(i, obj){
// get the width of each image
var image_width = $(this).width();
// if the viewport width is less than twice the image width then switch the classes
if(viewport_width < (image_width * 2)) {
$(this).removeClass('alignright');
$(this).addClass('aligncenter');
console.log('Viewport is less than twice image width');
} else {
console.log('Viewport is more than twice image width');
$(this).addClass('alignright');
$(this).removeClass('aligncenter');
};
});
});
});

If I am reading this correctly, (this).removeClass('alignright'); is changing your dom. Because of this all the link to the class alignright is now new but your jquery is still looking for the instances that have been removed.
Update $('.alignright').each(function(i, obj){ to be one level higher than what is being altered.
if the code is
<div id="outer-wrapper">
<div class="alignright">
content
</div>
</div>
use $('#outer-wrapper .alignright').each(function(i, obj){

Efficiently Find Page Max Dimensions

I am currently running a script on a third-party page to determine the maximum dimensions of the page. At first, this may seem as if I could just use outerWidth() and outerHeight() on my parent wrapper, #base but the problem is that the page wrapper isn't sized from its children. So I might have a parent that is 0x0 and its child is 400x400 and a child inside of that which is 500x500. It seems they just allow overflow. I have tried some CSS tricks in attempt to force the parent #base to size itself correctly, but the children don't seem to drive this change and modifying their CSS causes actual alignment issues on the page. Additionally, there are many hidden items on the page that do not become visible until later or during page interaction so this further prevents me from just grabbing the outer dimensions of #base or something like that.
My current approach is to iterate through every single element on the page. I check to see where it is positioned and what its dimensions are. Based on those, I update my maximum dimensions. I also have to check for horizontal and vertical scrolling elements because those may be on the page too. If a wrapper is 500px wide and the child has a width of 1000px, but is scrolled, I wouldn't want that to affect my maximum dimensions. Anyways, this approach works but it's slow. Sometimes the page may have +15k elements. With these numbers, it takes 10 seconds on my machine. I might be able to optimize some of the conditional statements to use booleans instead of evaluating values, but I don't think this will make a significant difference. I'm hoping there is some process I'm completely overlooking. Below is my current code snippet and a demo showing how the page looks prior to running the code and after the code has been run.
Demo: https://p826ni.axshare.com/#g=1&p=without_code
$('#base *').not('script, style').each(function () {
currentElement = $(this);
// Initialize on first loop.
if (parentElementHorizontal === undefined && parentElementVertical === undefined) {
parentElementHorizontal = currentElement;
parentElementVertical = currentElement;
}
width = currentElement.outerWidth();
height = currentElement.outerHeight();
scrollWidthHidden = currentElement[0].scrollWidth;
scrollHeightHidden = currentElement[0].scrollHeight;
top = currentElement.offset().top;
left = currentElement.offset().left;
// Check if we're still within the parent containing horizontal-scrolling overflow.
if (!$.contains(parentElementHorizontal[0], currentElement[0])) {
hiddenWidth = false;
}
// Check if we're still within the parent containing vertical-scrolling overflow.
if (!$.contains(parentElementVertical[0], currentElement[0])) {
hiddenHeight = false;
}
// Check if we've found an element with horizontal-scrolling content.
if (!hiddenWidth) {
maxWidth = maxWidth < left + width ? left + width : maxWidth;
} else if (currentElement.width() > maxWidth) {
currentElement.addClass('redline-layer');
}
if (scrollWidthHidden > width && !hiddenWidth && width > 0) {
hiddenWidth = true;
parentElementHorizontal = currentElement;
}
// Check if we've found an element with vertical-scrolling content.
if (!hiddenHeight) {
maxHeight = maxHeight < top + height ? top + height : maxHeight;
} else if (currentElement.height() > maxHeight) {
currentElement.addClass('redline-layer');
}
if (scrollHeightHidden > height && !hiddenHeight && height > 0) {
hiddenHeight = true;
parentElementVertical = currentElement;
}
});

JS: Removing class from section

I use parallax effect on my site, but when the screen is smaller the background images starts to be cut off a bit. I decided to have parallax effect only on desktops and to remove this from other smaller devices.
For example I have 3 sections:
<section class="bg1 parallax"></section>
<section class="bg2 parallax"></section>
<section class="bg3 parallax"></section>
Parallax class is not described in CSS, it is added just to let the JavaScript know to which section parallax should be included.
My question:
Has someone got a script which can remove class "parallax" if screen width is smaller than for example : 1280px ?
If width is bigger than 1280px
<section class="bg1 parallax"></section>
Otherwise
<section class="bg1"></section>

I haven't tested it, but this should put you in the right direction...
window.onresize = function(){ // may not be the window object
if (screen.width < 1280) { // many ways of detecting screen width
var sections = document.querySelectorAll("section"); // create array of all section elements
for (var i = 0; i <= sections.length-1; i++) { // loop through them
sections[i].classList.remove("parallax"); // remove their parallax class
};
};
};

It seems a bit hacky, but you could do something like:
// closure so we don't pollute global scope. This should be run at the bottom of the page so that it can find all of the parallax elements on the page
(function(){
var previous_width = 0;
var cutoff = 1280;
var $parallax_elements = $('.parallax');
function check_width() {
var current_width = document.body.clientWidth;
// if the document has gone from narrow to wide, re-enable parallax
if (current_width > cutoff && previous_width <= cutoff) {
$parallax_elements.addClass('parallax');
}
// if the document has gone from wide to narrow, disable parallax
else if (current_width <= cutoff && previous_width > cutoff) {
$parallax_elements.removeClass('parallax');
}
// store the current width for the next check
previous_width = current_width;
}
// run it every time the window resizes
$(window).resize(check_width);
// run it once to initialize
check_width();
})();

Tried this in console and seems to work.
if(window.innerWidth < 1280){
var parallaxes = document.getElementsByClassName('parallax');
while(parallaxes[0]){
parallaxes[0].classList.remove('parallax');
}
}

Add/Remove class from specific div based off screen size

I need to add the class .full-page when the screen size is >= 769px and remove the same class when screen size is <=768. The div I need the class to be applied to has an ID of #here I have tried quite a few things and this is where I left off...
<script>
var windowSize = window.innerWidth;
if (windowSize >= 769) {
console.log('Greater than 768');
document.getElementById('here').addClass = 'full-page';}
else (windowSize <= 768) {
console.log('Less than 768');
document.getElementById('here').removeClass = 'full-page';}
</script>
Anyone have a tip? Thanks in advance!

You can use window#matchMedia to detect width changes, and see if it matches a certain criteria. Use classList to add and remove classes.
You can see an example here. Change the width of the bottom right rectangle by dragging the border.
Code:
var classList = document.getElementById('here').classList;
var minWidth769 = window.matchMedia("(min-width: 769px)");
function match() {
minWidth769.matches ? classList.add('full-page') : classList.remove('full-page');
}
minWidth769.addListener(match);
match();

There is no method add|remove Class in JavaScript, if you want to change class for an element, you can use
document.getElementById('here').className = 'full-page'
OR
document.getElementById('here').setAttribute('class', 'full-page')

I think you need to use jQuery if you want to use 'addClass', after link the jQuery file,
Try
$("#here").addClass("full-page");
and
$("#here").removeClass ("full-page");

jQuery window width not equal to CSS's window width

I'm using the following two pieces of CSS and JS code:
#media (max-width: 720px) {
// a code to make arrows in a carousel disappear
}
if(jQuery(window).width() <= 720){
// a code to make arrows in the carousel stop working
}
The problem with them is that the latter executes on exactly width=738px and not 720px. I suspect that this is because of browser's vertical scrollbar that has width equal to 18px in Chrome.
Is there a way to unify this? I'd like these actions to happen at the same moment in all browsers regardless of the scrollbar's width.
Tests (when browser is # 720px and CSS has already executed):
jQuery(document).innerWidth() = 703
jQuery(window).innerWidth() = 703
jQuery(document).width() = 703
jQuery(window).width() = 703
jQuery('body').width() = 703
jQuery('html').width() = 703

I had to tackle the same problem a while ago, and so far the most correct solution I found is to use media queries to pass the actual window size to Javascript. You have to follow these steps:
Add a hidden element to your page,
Use media queries to alter the max-width property of that element,
Read back the max-width property of that element through Javascript.
For instance, add the following element to your page:
<div id="currentMedia"></div>
Then write the following CSS rules:
#currentMedia {
display: none;
}
#media (max-width: 720px) {
/* Make arrows in the carousel disappear... */
#currentMedia {
max-width: 720px;
}
}
Then, from the Javascript side, you can write:
if (parseInt(jQuery("#currentMedia").css("max-width"), 10) <= 720) {
// Make arrows in the carousel stop working...
}
And it will be accurate regardless of the scrollbar size, since the value comes from the same media query that triggers the carousel's disappearance.
I tested this solution on all major recent browsers, and it gives correct results.

You will find the big summary of what properties are supported on what browsers on this page on quirksmode.org.
Your best bet is probably to grab an element in the page (using document.body where supported, or document.getElementById or whatever), walk its offsetParent chain to find the topmost element, then examine that element's clientWidth and clientHeight.
innerWidth documentation
innerWidth() says this method is not applicable to window and document objects; for these, use .width()
try
How can I get the browser's scrollbar sizes?
From Alexandre Gomes Blog
function getScrollBarWidth () {
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);
};
in your code
if(jQuery(window).width()-getScrollBarWidth(); <= 720){
// a code to make arrows in the carousel stop working
}

A bit outdated thread, but i've found this solution
function getWidth(){
return ((window.innerWidth > 0) ? window.innerWidth : screen.width);
}

If you are using Bootstrap > 3 then I will suggest you something.
Bootstrap ships with .container class in its Css and predefined. And its altering with #media queries.So my working code sample for this is below.
function detectWidth(){
var width = $('.container').eq(0).outerWidth() ;
console.log(width);
if(width<750){
// do something for XS element
}else if(width>=750 && width<970){
// do something for SM element
}else if(width>=970 && width<1170){
// do something for MD element
}else{
// do something for LG element
}
}

I realize this is an old thread, but I think it can still benefit from this answer.
var width = window.outerWidth;
This will give you the width of the window including scrollbars, which is what media queries use, I believe.