Develop Reference

How to Dynamically Update outerHeight of An Element When Another Element Changes in Height on Window Resize?

Bit of a jquery / javascript noob question here. I have a subnav element that I am sticking to the bottom of my primary nav once someone hits a certain scroll point. To do that, I'm offsetting the subnav element by the height of the main nav element, as shown below.
$(function() {
$('.sticky-nav').stickybits({
useStickyClasses: true,
stickyBitStickyOffset: $('.navbar-fixed-top').outerHeight(),
});
});
The problem that I'm running into is '.navbar-fixed-top' has a different height at mobile / tablet and desktop sizes (the height changes at 992px) and the offset gets messed up if someone resizes the screen (i.e., if they start at desktop, and then resize to mobile / tablet, there's too much space above the subnav because the main nav was taller in desktop).
My question is, how can I update the code above to dynamically update the outerHeight when the height of the .navbar-fixed-top element changes?
I tried the code below, inspired by the answer to this question: Resize element width on window resize jquery, but it's not working
$(function() {
var topNavHeight = $('.navbar-fixed-top').outerHeight();
$(window).on('resize', function(event) {
var topNavHeight = $('.navbar-fixed-top').outerHeight();
});
$('.sticky-nav').stickybits({
useStickyClasses: true,
stickyBitStickyOffset: topNavHeight,
});
});
Thanks!

I think this will work:
$(function() {
let stickything;
function set_sticky() {
if (stickything) {
stickything.cleanup();
}
stickything = $('.sticky-nav').stickybits({
useStickyClasses: true,
stickyBitStickyOffset: $('.navbar-fixed-top').outerHeight(),
});
}
$(window).on('resize', set_sticky);
set_sticky();
});
Just changing a variable isn't enough, you have to tell stickbits to update. There doesn't seem be a way to update the offset so this just reinitializes it.

How to make scrollbar to see full content in below case?

see demo url of the framework i'm using: http://alvarotrigo.com/fullPage/examples/navigationH.html#secondPage
However,using almost same kind of code from above,
when I try to achieve below effect in which title text is excluded from slider. (title text to be static, and content is sliding)
jsfiddle url: http://jsfiddle.net/097wvnot/8/
I can't scroll to see all the content; what's the best code to achieve this effect?
if i want to use the top framework, must i do a lot of hack into its core functions?
if not hacking the top animation framework , what are other recommendations to this effect

Use an absolute positioned element for your title. Fullpage.js calculates the height of your content inside the slide elements. (as they are suppose to be full height...).
If you place anything outside any slide, it would have to be absoluted positioned.
Take a look at the solution I propose: http://jsfiddle.net/097wvnot/11/
I added the following style to your title:
#demo{
position:absolute;
top:50px;
margin: 0;
left:0;
right:0;
text-align:center;
}

It looks like the plugin is calculating the height of the fp-scrollable incorrectly. At least for your use case. I was able to get it looking good by just manually adjusting the fp-scrollable's height attribute to a smaller amount (obviously that is not a long term fix, just something I was doing for testing). I'm not sure if the calculating takes into account your font size, and things like that, so that might effect it.
If you want to hack on the plugin, generally the place you need to make your changes is fairly restricted, and wouldn't be too bad. From the github page. https://github.com/alvarotrigo/fullPage.js/blob/master/jquery.fullPage.js
All you need to do is fix the value being placed into the scrollHeight variable. I'm not sure exactly what it's not accounting for in the scroll height calculation (the scrollHeight needs to be smaller in your case, it's too big), but I think that's an exercise you can try your hand at first :) I've got to get to bed z.z
You also may need to mess with the calculation for the contentHeight, since ostensibly you'll be shrinking the scrollHeight, and the script only puts the scroll bar on there if the content is bigger than the scroll.
function createSlimScrolling(element){
//needed to make `scrollHeight` work under Opera 12
element.css('overflow', 'hidden');
//in case element is a slide
var section = element.closest('.fp-section');
var scrollable = element.find('.fp-scrollable');
//if there was scroll, the contentHeight will be the one in the scrollable section
if(scrollable.length){
var contentHeight = scrollable.get(0).scrollHeight;
}else{
var contentHeight = element.get(0).scrollHeight;
if(options.verticalCentered){
contentHeight = element.find('.fp-tableCell').get(0).scrollHeight;
}
}
var scrollHeight = windowsHeight - parseInt(section.css('padding-bottom')) - parseInt(section.css('padding-top'));
//needs scroll?
if ( contentHeight > scrollHeight) {
//was there already an scroll ? Updating it
if(scrollable.length){
scrollable.css('height', scrollHeight + 'px').parent().css('height', scrollHeight + 'px');
}
//creating the scrolling
else{
if(options.verticalCentered){
element.find('.fp-tableCell').wrapInner('<div class="fp-scrollable" />');
}else{
element.wrapInner('<div class="fp-scrollable" />');
}
element.find('.fp-scrollable').slimScroll({
allowPageScroll: true,
height: scrollHeight + 'px',
size: '10px',
alwaysVisible: true
});
}
}
//removing the scrolling when it is not necessary anymore
else{
removeSlimScroll(element);
}
//undo
element.css('overflow', '');
}

JS / jQuery How to get height of dynamic (responsive) div?

I have not been able to find an answer that works for me on SO.
Basically I have a div with an image that has fixed positioning. It is responsive and will shrink or grow to whatever the screen size is.
What I want to do is get the height anytime the screen size changes and input it as a positioning value for another div so that it there is no overlapping (due to the fixed positioning).
I can get the height initially but it never changes after the first value when the screen is being resized.
quick demo up here: link
look in console to see height being returned. notice that it doesn't change when browser is resized.
JS
$(function(){
var explore = $('#explore').height();
console.log(explore);
$( window ).on("resize", function() {
console.log(explore);
});
});
I've also tried .css("height") but that didn't fix the issue.
*note the div does not have fixed positioning on this example since it would make the layout more confusing

You are not modifying explore:
Change it as follows:
$(function(){
var explore = $('#explore').css("height");
console.log(explore);
$( window ).on("resize", function() {
explore = $('#explore').css("height");
console.log(explore);
});
});

You need to add a resize listener to the window like so:
function repositionDivOnResize() {
// this is where you'll dynamically reposition your element
}
$(window).on("resize", repositionDivOnResize)

How to give navigation 100% width in pixels upon resize?

So basically, I am attempting to use jQuery to give my navigation bar (Bootstrap navbar) a 100% width, but in pixels.
Of course, this has to be determined every time the browser/window is resized.
I came up with this, although it is extremely buggy. It uses the starting width of 'nav' as 'navsize', and upon resize of the window, navsize still stays the same.
$(document).on('ready', function () {
$(window).on('resize', function () {
var navsize = $('nav').width();
$('nav').css('width', navsize);
}).trigger('resize');
});
I have also tried var navsize = $('nav').innerWidth(); which was also no good.
The function is definitely being called upon resize since I have tested with console.log()
For all those who are wondering why I am doing this, I am using StickyJS to make my navigation scroll with the page. Although, since it is using 100% width, upon scrolling it becomes much smaller since the nav leaves its container.

This should work
$(document).on('ready', function () {
$(window).on('resize', function () {
$('nav').css('width', 'calc(100% + 1px - 1px)' );
console.log( $('nav').width() );
/// Use following ONLY if you specifically want to set the width in pixel
$('nav').width($('nav').width());
}).trigger('resize');
});
the console.log will have your width in pixel. Means whenever in future you will read the width , it will be in pixel.
calc(100% + 1px - 1px) converts the width and sets in px units, which we can read later on.

Are you sure that $('nav') exists?
I've done some testing using a basic bootstrap page and a slightly change of your code works.
Navigate to this page and open the console inspector.
http://getbootstrap.com/examples/starter-template/
paste the following code and you will see that the .navbar width will be logged on window resize.
$(window).on('resize', function () {
var navsize = $('.navbar').width();
console.log(navsize)
});
Cheers.

It'd be easier with the supporting HTML and CSS, but I will venture a guess based on the behavior alone.
Best Guess
It sounds like one of these options is likely.
you meant to use #nav, .nav, div.nav, etc and don't actually mean to select a "nav" element
your "nav" element is not display inline-block|block, which occurs in some browsers
you are using the "nav" tag in a browser that doesn't support it (IE 8)
your JS library doesn't support the "nav" tag
Alternative
Use JS to relocate your nav into the body (at the appropriate scroll depth) and give your html , body, and nav tags width 100%
Hope that helps.

jquery (windows).height increase every time I resize the window

I want to resize a div on resize of the window to make it fill the entire browser window...
I searched a lot on internet finding a solution, but everything I tried cause the same problem...
at first load of the page it works well, but when I try to resize the window the value of bodyheight keeps increasing...
this is my code
$(document).ready(function() {
body_sizer();
$(window).resize(body_sizer);
});
function body_sizer() {
var bodyheight = $(window).height();
$("#contenitore_full").css('height', bodyheight);
}
EDIT
OK!!! my fault as i thought :)
problem was caused by a wrong way to call jquery in wordpress.
i'm sorry for let you loose time
thanks a lot everyone
ale

You don't need javascript to achieve what you want. All you need is CSS.
Here's a fiddle
CSS
body, html { margin:0; height:100% }
#contenitore_full { border:1px solid #FF0000; width:25%; height:99%; display:block; }
HTML
<div id="contenitore_full"></div>
The thing is in order for height to work, the parent's height also needs to be defined. That's why the height of the body and html tags also have a height of 100%.

It looks like your 'body_sizer' function might not be firing. Add your parens () to the end of it or either create an handler function inside .resize()
$(window).resize(function() {
var bodyheight = $(window).height();
$("#contenitore_full").css('height', bodyheight);
});

I had the exact same problem. I recommend using javascript instead of jQuery.
const width = window.innerWidth;
const height = window.innerHeight;