Develop Reference

How to update sticky menu's CSS positioning on window resize

I've built a sticky navbar based on an example from W3 schools. It's working very well — except when I resize the window, the alignment of the nav menu to the page content is incorrect.
You'll see that I've got some code that finds the correct offset for left side of menu, by checking another element on the page. It then adds some left padding to align it properly. (Without this, the position:fixed value just sends the sticky nav to the far left of the page).
This works great on scroll! However, if the window is resized horizontally, that left padding value doesn't update.
I've tried a few iterations of $(window).resize but haven't been able to get it to work. I'm sure it's an easy line of code I'm just not figuring out. Thanks in advance!
setTimeout(function () {
// When the user scrolls the page, execute myFunction
window.onscroll = function() {myFunction()};
// Get the navbar
var navbar = document.getElementById("app");
// Get the offset position of the navbar
var sticky = $("#app").offset().top
// Find correct offset for left side of menu (by checking #title element)
var element = document.getElementById('title');
var leftPos = element.getBoundingClientRect().left + window.scrollX;
var roundLeft = (Math.round(leftPos)) - 5;
// Add the sticky class to the navbar when you reach its scroll position. Remove "sticky" when you leave the scroll position
function myFunction() {
if (window.pageYOffset >= sticky) {
navbar.classList.add("sticky")
navbar.style.cssText = "padding-left:" + roundLeft + "px!important";
} else {
navbar.classList.remove("sticky");
navbar.style.cssText = "padding-left:inherit";
}
}
}, 4000);
.sticky {
position: fixed;
top: 0;
width: 100%;
background: rgba(255, 255, 255, 0.99);
z-index: 9 !important;
max-width: none !important;
box-shadow: 0px 1px 10px #999;
}
(I'm using setTimeout because our Shiny app takes a few seconds to load and for the content to populate.)

You should use pure CSS solution with position: sticky
It does have acceptable percentage of browser support:
https://caniuse.com/#feat=css-sticky
Since it's just the styling, it may be fine to show it static in the old browsers.

Sticky menu works. Sorta

I'm attempting to resolve an issue with a "sticky" horizontal menu.
It technically works, in that the menu's position is fixed while the pages scrolls up and down.
The issue at the moment is that then the page is scrolled back up to the original position, the new resting place of the objects below the sticky menu return to the top of the browser. If that makes sense.
Here's the javascript in use:
<script>
// When the user scrolls the page, execute myFunction
window.onscroll = function() {myFunction()};
// Get the navbar
var navbar = document.getElementById("navbar_cont");
// Get the offset position of the navbar
var sticky = navbar.offsetTop;
// Add the sticky class to the navbar when you reach its scroll position. Remove "sticky" when you leave the scroll position
function myFunction() {
if (window.pageYOffset >= sticky) {
navbar.classList.add("sticky")
} else {
navbar.classList.remove("sticky");
}
}
</script>
And the accompanying css
.sticky {
position: fixed;
top: 0;
width: 100%;
}
.sticky + #call-to-action {
padding-top:164px;
}
Any help would be appreciated. Thanks!

make div scoll untill it reaches top of page then fixed

let's get straight to the point:
My code looks like the following:
<div id="keep_up">
<div id="thread_menu">
<div id="new_thread">
</div>
</div>
</div>
And my css:
#keep_up {
position: fixed;
width: 13%;
}
#thread_menu{
height: 80vh;
width: 100%;
float: left;
position: relative;
}
Now i use this for a forum. and this is basically to show the active and new threads on the side of the screen.
However. When watching a thread, the header disappears (Wich makes sense because we are scrolling down).
but i want the thread menu to stay on my side (So that it is always visible). In this case that is happening because my keep_up div has position: fixed. But i only see half of the thread menu becuase it is too long and won't scroll up.
My question:
I want the thread menu to scroll up, untill it reaches the top of my window. From then on i want it to stay there.
How do i do this?
I saw a few examples but none of them worked for me.
EDIT: Code i tried:
<script src="jquery.min.js">
$(window).scroll(function () {
var margin = null;
$(window).on("scroll", function () {
var scrollHeight = $(document).height(),
scrollTop = $(window).scrollTop(),
offsetBottom = 110, // Offset depending on the height of the footer
offsetTop = 100, // Offset depending on the height of the header
positionTop = $(".keep_up").offset().top,
affix;
if (margin != null && (scrollTop + margin <= positionTop)) {
// The sidebar has reached the bottom and is still on the bottom
affix = false;
} else if (positionTop + $(".keep_up").height() >= scrollHeight - offsetBottom) {
// The sidebar has reached the bottom
affix = 'bottom';
} else if (scrollTop <= offsetTop) {
// The sidebar has reached the top
affix = 'top';
} else {
// The sidebar is midway
affix = false;
}
// If the sidebar hasnot changed his state, return;
if ($(".keep_up").hasClass('at' + (affix ? '-' + affix : ''))) return;
if (affix == 'bottom') {
margin = positionTop - scrollTop;
} else {
margin = null;
}
// If the related class is added to the div
$(".keep_up").removeClass('at at-top at-bottom').addClass('at' + (affix ? '-' + affix : ''))
});
});
</script>
And the CSS:
.keep_up{
/*position: fixed;*/
width: 13%;
}
.keep_up.at {
top: 1px;
position: fixed;
}
.keep_up.at-top{
}
.keep_up.at-bottom {
top: 438px;
position: absolute;
}

modify this on HTML:
<div id="prevent"></div>
<div id="keep_up" data-spy="affix" data-offset-top="200">
Add this CSS:
.affix{position: fixed !important; top:0px; z-index:999;}
.affixpatch{margin-top:100px !important;}
this will fix the div when you scroll down 200px. Change data-offset-top value to reach it on different break point.
.affixpatch is a class that will be loaded with next jquery function. it prevents to hide content behind top fixed div. Change margin-top to another value if this don't solves the "hide content" problem that always generate affixing divs.
<script>
$(function() {
//caches a jQuery object containing the header element
var header = $(".affix");
$(window).scroll(function() {
var scroll = $(window).scrollTop();
if (scroll >= 200) {
$('#prevent').addClass("affixpatch");
} else {
$('#prevent').removeClass("affixpatch");
}
});
});
</script>
Hope it helps. If not, you may have some class that rewrite or impede the correct function of this affix.
I've tested this hundreds of times, usually to fix navbars.
SCROLL:
Using overflow to scroll content:
#keep_up{
max-height:400px;
width: auto;
overflow:auto;}
This will scroll the content inside #keep_up div (or use it in another one)
NOTE: you must declare a fixed max height for this div. Set max-width only if you need.
You can use %, em, rem... no need to be px for fix the max witdth. (to get a responsive effect, use responsive measurements)

If I understand your scenario correctly, the way to do this might be to use jQuery (or native JS, but you've tagged jQuery so I'm assuming that's in play).
There's a plugin that handles this kind of thing: http://leafo.net/sticky-kit/
I'd suggest you look at the plugin source code to see how it works - an event handler function on $(window).scroll() which then toggles classes on your #thread_menu to fix it in place. To keep your code lightweight, you probably don't need everything the plugin provides.

Scrolling Two Divs Using JQuery/Javascript

Wrapper - Overflow Hidden
Div One: Sidebar
Div Two: Main Content
Div Two will have a normal scroll. Div One I wish to have no visible scroll however when you scroll Div One it scrolls Div Two.
Upon Div One's height hitting the bottom, it will no longer scroll and visa-versa for scrolling back up.
This will result in the sidebar always being visible at the side. Before you ask, I've tried all positioning types to get this to work resulting in many failed attempts.
My live demo can be seen here: http://rafflebananza.com/admin/newadmin.html#
Note I've tried to make a JSFiddle simplified but my maths does not seem to work in there the same. Please suggest whether I should fork all my page to there or whatnot for future visitors needing the same help.
Overview
Scrolling in the wrapper will scroll sidebar to point x only (x being the sidebars height) then stopping but will continue to allow the content to be scrolled. Visa-versa for scrolling back up.
Somewhat half way there...
var scrollTop = (window.pageYOffset !== undefined) ? window.pageYOffset : (document.documentElement || document.body.parentNode || document.body).scrollTop,
position = document.body.scrollTop;
function scrollD() {
var scroll = document.body.scrollTop;
if (scroll > position) {
// Scrolling Down Functions
} else {
// Scrolling Up Functions
}
position = scroll;
}

Updated the answer to match OPs requirements.
I downloaded your website in its current state and made the following changes to your code:
var scrollY = 0;
$(window).scroll(function() {
var sideNav = $('.SideNav'); // The side navigation
var wScrollY = $(this).scrollTop(); // Current scroll position of Window
var navHeight = sideNav.height(); // Height of the Navigation
var StageHeight = $(window).height() - 46; // The display space
if(sideNav.height() > StageHeight) { // Do the following if the side navigation is higher than the display space
var spaceLeft = sideNav.height() - StageHeight; // spaceLeft -> how many pixel left before fixing navigation when scrolling
if(scrollY < wScrollY) { // Scroll direction is down
if (wScrollY >= spaceLeft) // If scroll top > space left -> fixate navigation at the bottom, otherwise scroll with the content
sideNav.css({top:46-spaceLeft+wScrollY});
if (wScrollY <= 46) // Set top strict to 46. Sometimes there is white space left, caused by the scroll event.
sideNav.css({top:46});
} else { // Scroll direction is up
var sideNavTop;
if (sideNav.offset().top < 0) {
sideNavTop = Math.pow(sideNav.offset().top); // if top is negative, make it positive for comparison
} else {
sideNavTop = sideNav.offset().top;
}
if (sideNavTop > (46+wScrollY)) // Fixate the header if top of navigation appears
sideNav.css({top:46+wScrollY});
}
} else {
sideNav.css({top:46+wScrollY}); // Fixate always
}
scrollY = wScrollY;
});
This will let you scroll your side navigation up until its end. Then fixate. If you scroll up, it will still be fixated until your reach the point, where the navigation must scrolled back to its original position.
You can check the edited version here: http://pastebin.com/Zkx4pSKe
Just copy the raw code into a blank html page and try it out.
It's a bit messy and maybe not the best solution, but it works.

Ok, here you go:
var $sidebar = $('.sidebar'),
$window = $(window),
previousScroll = 0;
$window.on('scroll', function (e) {
if ($window.scrollTop() - previousScroll > 0) {
$sidebar.css({
'top': Math.max($window.scrollTop() + $window.height() - $sidebar.outerHeight(true), parseInt($sidebar.css('top'))) + 'px'
});
} else {
$sidebar.css({
'top': Math.min($window.scrollTop(), parseInt($sidebar.css('top'))) + 'px'
});
}
previousScroll = $window.scrollTop();
});
http://jsfiddle.net/7nwzcpqk/1/

i might have misunderstood your desired result incorrectly but you can see if this works for you :
.SideNav {
position: fixed; // you currently have this as position:absolute;
}

You don't need nor a wrapper element nor jQuery. I assume that you are using a wrapper because you want to have the top bar placed there. I think there is a better way to do it by using simply three divs.
The top bar has to be fixed (to be always visible) and of full width.
The side bar also has to be fixed (to be always visible) with a top margin of the height of the top bar.
The content needs just a left padding (width of side bar) and top padding (height of top bar).
Here is the example code (http://jsfiddle.net/zckfwL4p/):
HTML
<div id="top_bar"></div>
<div id="side_bar">links here</div>
<div id="content"></div>
CSS
body {
margin:0px;
padding:0px;
}
#side_bar {
width:50px;
position: fixed;
left:0px;
top:20px;
background-color:blue;
}
#top_bar {
position:fixed;
height:20px;
left:0px;
right:0px;
background-color:red;
}
#content {
position:relative;
padding-left:55px;
padding-top:25px;
}

How to change div img when scrolling down a page

Pretty simple javascript issue that I am not sure how to do:
When scrolling down on the website:
http://cerebral-supplements.myshopify.com/ (use password "aiglog")
the header shifts up into a minimalistic design. As the logo is too big it sticks out.
What javascript code would be needed to change the logo's div properties to resize the image?
Thanks

If you can add custom CSS, add the following:
/* scale logo down to ~75% size when scrolled sidebar is activated (fadeInDown class) */
.fadeInDown .template-logo img {
width: 225px;
height: 61px;
}

modify the functions values to your needs.
function onScrollChange()
{
if ( document.body.scrollTop > 500 ) {
var divElement = document.getElementById('divID');
// either change style properties directly
divElement.style.width = '100px';
divElement.style.height = '100px';
// or change the div's css class
divElement.classname = 'smallLogoClass';
}
}
than register it, so it executes on each scroll.
document.addEventListener('scroll', onScrollChange);