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Hide the upper part of the navbar when scroll (smoothly!)

Hello I customized a Bootstrap navbar with 2 rows (the upper part is just logo and social links and the down part are navigation links). I am trying to hide the upper part when scrolling but I can't find a way to do it smoothly. I think the code below is the best solution I found, but for now the eventlistener on transitionend doesn't work and the class 'hidden' is never added.
var scrollpos = window.scrollY;
var header = document.getElementById("header-up-section");
function add_class_on_scroll() {
header.classList.add('visuallyhidden');
header.addEventListener('transitionend', function(e) {
header.classList.add('hidden');
}, {
capture: false,
once: true,
passive: false
});
}
function remove_class_on_scroll() {
header.classList.remove('hidden');
setTimeout(function () {
header.classList.remove('visuallyhidden');
}, 20);
}
window.addEventListener('scroll', function(){
scrollpos = window.scrollY;
if(scrollpos > 20){
add_class_on_scroll();
}
else {
remove_class_on_scroll();
}
console.log(scrollpos);
});
*/and CSS :
#header-up-section.visuallyhidden {
opacity: 0;
}
#header-up-section.hidden {
display: none !important;
}
The header-up-section turns invisible but the div is not hidden. Any idea to help?

Finally no need for JS to do this. Just need 2 bootstrap navbars and add to the second one (which is a pseudo 'down part' of a two rows navbar) the bootstrap class 'sticky-top'. It does the job perfectly ;)

On scroll, logo color changes, but scrolling back up it stays the same

Im creating a fixed header where on load, the logo is flat white. On scroll, it changes to the full color logo.
However, when scrolling back to the top, it stays the same colored logo instead of going back to white.
Here's the code (and a pen)
$(function() {
$(window).scroll(function() {
var navlogo = $('.nav-logo-before');
var scroll = $(window).scrollTop();
if (scroll >= 1) {
navlogo.removeClass('.nav-logo-before').addClass('nav-logo-after');
} else {
navlogo.removeClass('.nav-logo-after').addClass('nav-logo-before');
}
});
});
http://codepen.io/bradpaulp/pen/gmXOjG

There's a couple of things here:
1) You start with a .nav-logo-before class but when the logo becomes black you remove that class and then try to get the same element using a class selector that doesn't exist anymore
2) removeClass('.nav-logo-before') is different than removeClass('nev-logo-before), notice the "." in the first selector.
3) You get the element using the $('.selector')in every scroll event, this can be a performance issue, it's better to cache them on page load and then use the element stored in memory
4) It's not a good practice to listen to scroll events as this can be too performance demanding, it's usually better to use the requestAnimationFrame and then check if the scroll position has changed. Using the scroll event it could happen that you scroll up really fast and the scroll event doesn't happen at 0, so your logo won't change. With requestAnimationFrame this can't happen
$(function() {
var navlogo = $('.nav-logo');
var $window = $(window);
var oldScroll = 0;
function loop() {
var scroll = $window.scrollTop();
if (oldScroll != scroll) {
oldScroll = scroll;
if (scroll >= 1) {
navlogo.removeClass('nav-logo-before').addClass('nav-logo-after');
} else {
navlogo.removeClass('nav-logo-after').addClass('nav-logo-before');
}
}
requestAnimationFrame(loop);
}
requestAnimationFrame(loop);
});
body {
background-color: rgba(0,0,0,.2);
}
.space {
padding: 300px;
}
.nav-logo-before {
content: url(https://image.ibb.co/kYANyv/logo_test_before.png)
}
.nav-logo-after {
content: url(https://image.ibb.co/jYzFJv/logo_test_after.png)
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div>
<img class="nav-logo nav-logo-before">
</div>
<div class="space">
</div>

Dont need to add the dot . in front of the class name in removeClass and addClass:
Use this:
navlogo.removeClass('nav-logo-before')
Secondly, you are removing the class that you are using to get the element in the first place.
I have an updated codepen, see if this suits your needs: http://codepen.io/anon/pen/ZeaYRO

You are removing the class nav-logo-before, so the second time the function runs, it can't find any element with nav-logo-before.
Just give a second class to your navlogo element and use that on line 3.
Like this:
var navlogo = $('.second-class');
working example:
http://codepen.io/anon/pen/ryYajx

You are getting the navlogo variable using
var navlogo = $('.nav-logo-before');
but then you change the class to be 'nav-logo-after', so next time the function gets called you won't be able to select the logo using jquery as it won't have the '.nav-logo-before'class anymore.
You could add an id to the logo and use that to select it, for example.
Apart from that, removeClass('.nav-logo-before') should be removeClass('nav-logo-before') without the dot before the class name.

The problem is that you removes nav-logo-before and then you want to select element with such class but it doesn't exist.
I've rafactored you code to avert it.
Another problem is that you uses dot in removeClass('.before') while it should be removeClass('before') - without dot
$(function() {
var navlogo = $('.nav-logo');
$(window).scroll(function() {
var scroll = $(window).scrollTop();
if (scroll >= 1) {
navlogo.removeClass('before').addClass('after');
} else {
navlogo.removeClass('after').addClass('before');
}
});
});
body {
background-color: rgba(0,0,0,.2);
}
.space {
padding: 300px;
}
.before {
content: url(https://image.ibb.co/kYANyv/logo_test_before.png)
}
.after {
content: url(https://image.ibb.co/jYzFJv/logo_test_after.png)
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div>
<img class="nav-logo before">
</div>
<div class="space">
</div>

How can I hide a button when scrolled to the top of a page?

I'm trying to adapt this JSFiddle to make the menu button on my website hide when I'm at the top of the page and show when I start scrolling down.
I modified the JS to match the CSS on my site. Then I placed it in tags in the head of my page
var $scb = $('<div class="toggle-menu-wrap"></div>');
$('.top-header').append($scb);
var $ccol = $('.content');
$ccol.scroll(function(){
$scb.stop(true,true).fadeTo(500, $ccol.scrollTop() > 10 ? 1 : 0);
});
However, it still doesn't work. Am I making a mistake in how I'm modifying the JS to fit my CSS?

You can include the toggle-menu-wrap element in your HTML from the start. There is no need to insert it using JS.
Write the one line of CSS you need, which is to hide the element from the beginning
.toggle-menu-wrap {
display: none;
}
Your version of jQuery uses 'jQuery' instead of '$' to reference itself. I would also re-write your JS like:
jQuery(document).ready(function() {
fadeMenuWrap();
jQuery(window).scroll(fadeMenuWrap);
});
function fadeMenuWrap() {
var scrollPos = window.pageYOffset || document.documentElement.scrollTop;
if (scrollPos > 300) {
jQuery('.toggle-menu-wrap').fadeIn(300);
} else {
jQuery('.toggle-menu-wrap').fadeOut(300);
}
}

Like #murli2308 said in the comments above, you need to attach a scroll event listener to the window:
$(document).ready(function () {
var $scb = $('<div class="scroll-border"></div>');
$('.above').append($scb);
var $ccol = $('.content');
$(window).scroll(function(){
$scb.stop(true,true).fadeTo(500, $ccol.scrollTop() > 10 ? 1 : 0);
});
})
Wrapping your code in $(document).ready() would also be a good idea.
The reason $ccol.scroll(function() { ... works in that fiddle is because of the CSS:
.content{
height: 200px;
width: 200px;
overflow: auto;
}
Notice overflow: auto;. This causes that specific div to be scrollable. However, on your website, you scroll the entire page, not $ccol. This means the event handler will never fire a scroll event (since $ccol will never scroll).

You might have forgotten to link Jquery.
<script type="text/javascript" src="http://code.jquery.com/jquery-1.8.3.min.js"></script>
Link this inside your head tag incase.....

This should do the job:
$(window).scroll(function(e){
if ($(this).scrollTop() > 0) {
$(".your_element").css("display", "block");
} else {
$(".your_element").css("display", "none");
}
});

Div Transitions - IE vs. others

I have a JSFiddle that displays a series of boxes. If one of the boxes is clicked, it expands to cover the other boxes, then displays text. When the now expanded box is clicked, it retracts to its original width and height. This javascript works flawlessly in Firefox, Chrome, and Safari. However, in Internet Explorer (v10), the box expands but fails to retract. Any Insight on why this may be?
JSFiddle: http://jsfiddle.net/QBdDE/
Javascript:
$('div').on('click', function (e) {
if ($(this).hasClass('clicked')) {
setTimeout(function (div) {
return function () { div.css('z-index', '') ; } ;
} ($(this)), 1000) ;
$('.overlay-text').hide();
}
else {
$(this).css('z-index', 400) ;
setTimeout(function(){$('.overlay-text').show();},1000);
}
$(this).toggleClass('clicked') ;
});

What's Going On
Problem:
pointer-events support was added in IE11. IE10 is ignoring this, and because your overlay is on top, the mouse is interacting with it. We can get around this though!
Solution:
We need to remove dependency on that CSS rule. To do this, we need to do two things:
1.) We need to make the hover color stays applied even if the :hover effect isn't happening. We can add another selector to our CSS so that the .clicked class will cause the colors.
2.) We need to address what happens when .overlay_text is clicked, and use that to trigger the shrinking animation.
Code
1.) Hover Effect
We need to add in another select to every place :hover is used:
Old CSS:
.first_box:hover {
...background color rule ...
}
New CSS:
.first_box:hover, .first_box.clicked {
...background color rule ...
}
Duplicate the above for all 4 box rules.
2.) .overlay-text Trigger
We need to cause a click on .overlay-text to trigger the shrinking.
Old JS:
$('div').on('click', function (e) {
if ($(this).hasClass('clicked')) {
setTimeout(function (div) {
return function () { div.css('z-index', '') ; } ;
} ($(this)), 1000) ;
$('.overlay-text').hide();
}
else {
$(this).css('z-index', 400) ;
setTimeout(function(){$('.overlay-text').show();},1000);
}
$(this).toggleClass('clicked') ;
});
New JS:
We have to add a new selector to the .on() code, then we have to add .clicked to both the selected square, add the overlaying section. Finally we have to remove .clicked from both. We can't use .toggleClass() because we are adding to $(this) and removing from all divs.
$('div, .overlay-text').on('click', function (e) {
if ($(this).hasClass('clicked')) {
setTimeout(function (div) {
return function () { div.css('z-index', '') ; } ;
} ($(this)), 1000) ;
$('.overlay-text').hide();
$('div').removeClass('clicked');
$('.overlay-text').removeClass('clicked');
}
else {
$(this).css('z-index', 400) ;
setTimeout(function(){$('.overlay-text').show();},1000);
$(this).addClass('clicked');
$('.overlay-text').addClass('clicked');
}
});
Summary
I've tested in IE10 and it works.
Working Example:
Extra
If I may say, the CSS structure you are using could be improved and your animations will look a lot better. Chrome and IE both flicker during the animation of the two left blocks.
This is because their width AND position is being animated. If you position them from right:0, only their width will animate and it'll look a lot smoother.
I've created a Fiddle for you to address the above. I used absolute positioning. The CSS ends up being shorter, but mainly the animation doesn't flicker. Take a look:
Working Example:
Extra 2
As per comments from OP, we are going to prevent users from double clicking. Since all animations take 1 second, we will disable clicking from triggering anything for 1 second after each click.
It's actually pretty simple to do. In the Extra 1 above, we cleaned up the JS, and it became this:
$('div, .overlay-text').on('click', function (e) {
if ($(this).hasClass('clicked')) {
$('.overlay-text').hide();
$('div').removeClass('clicked');
$('.overlay-text').removeClass('clicked');
}
else {
setTimeout(function(){$('.overlay-text').show();},1000);
$(this).addClass('clicked');
$('.overlay-text').addClass('clicked');
}
});
We just need to add a global variable that starts true. When once the click happens, set it to false immediately, and after 1 second, set it to true. Then we just check to see if it's true, and don't do anything at all if it's false:
var notdouble = 1;
$('div, .overlay-text').on('click', function (e) {
if (notdouble) {
if ($(this).hasClass('clicked')) {
$('.overlay-text').hide();
$('div').removeClass('clicked');
$('.overlay-text').removeClass('clicked');
}
else {
setTimeout(function(){$('.overlay-text').show();},1000);
$(this).addClass('clicked');
$('.overlay-text').addClass('clicked');
}
notdouble=0;
setTimeout(function(){notdouble=1;},1000);
}
});
Working Example:
Note, this builds from the new structure in the Fiddle version 13, so it won't work exactly with the fixed version of the original structure. The concept can be adapted though.

Not working in IE 9 as the div click event never fires. I think it's covered by the section with class="overlay-text". But I've got a workaround by handling the click event of the section and triggering the div click event
$('section').on('click', function (e) {
$('.overlay-text').hide();
$( "div" ).addClass('clicked') ;
$( "div" ).trigger( "click" );
});

Attach and detach affixed headers with Twitter Bootstrap

I'm trying to use the affix function to attach a header to the top of the screen, but have it attached only for a portion of the page. It should detach (and scroll up along with the content) when the user scrolls past a certain point.
I'm using the script from this jsfiddle.
What I'm trying right now is this:
$('#nav-wrapper').height($("#nav").height());
$('#nav').affix({
offset: $('#nav').position()
});
$('#nav').detached({
offset: $('#bottom').position()
});
With the .detached class like so:
.detached { position: static; }
Can't get this to work. Any suggestions?

Twitter Bootstrap affix module doesn't have that option. But, I've used many times hcSticky, it is awesome. Take a look, it's simply to use and works very well.

You can write the logic in a function, and pass it to affix as offset.top.
Try
var navHeight = $("#nav").height();
var detachTop = $("#detach").offset().top;
var navTop = $("#nav-wrapper").offset().top;
$('#nav-wrapper').height(navHeight);
$('#nav').affix({
offset : {
top : function() {
if ((navHeight + $(window).scrollTop()) > detachTop) {
return Number.MAX_VALUE;
}
return navTop;
}
}
});
Fiddle is here.

Another option which might work for you: http://jsfiddle.net/panchroma/5n9vw/
HTML
<div class="header" data-spy="affix">
affixed header, released after scrolling 100px
</div>
Javascript
$(document).ready(function(){
$(window).scroll(function(){
var y = $(window).scrollTop();
if( y > 100 ){
$(".header.affix").css({'position':'static'});
} else {
$(".header.affix").css({'position':'fixed'});
}
});
})
Good luck!