Develop Reference

Run jQuery/Javascript Function w/GSAP only once?

I have a function that scrolls down/snaps to a div after the user starts to scroll (to avoid them having to manually scroll down to where the main content starts). I have used some GSAP to achieve this, however I don't think that will make much difference with the solution to this problem. However, while this function does exactly what I'd like, It won't then allow the user to scroll back up. It just glitches a little bit, as if I'm fighting with the function to scroll back up. I've tried a variety of answers from all the "run only once questions" on here, but none seem to work in this situation.
I want to basically kill the function after the first time it is initiated, or to tweak the function to only work on the first scroll at the top of the page (though I appreciate this would be much more complicated).
Thank you in advance of any help.
JS:
$(window).scroll(function () {
function headScrollToDiv() {
var dHeight = $(window).height();
if (dHeight >= $(this).scrollTop()) {
gsap.to(window, 0.4, { scrollTo: ".buffer" });
}
}
headScrollToDiv();
});

Add a "cooldown" to this Javascript that is triggered by mousewheel

I'm working with a Squarespace theme and ran into a little bit of an experience I was hoping y'all may be able to help me fix.
The page has a series of images that scroll horizontally. By default, scrolling does nothing. The below code was provided on the forums to make the scroll control the images by clicking the left or right arrows.
I was wondering what the best and most efficient way to add a simple "cooldown" effect to the function so that there is full delay before the next scroll.
Currently, the scroll just cycles through 3 or four and is very sensitive. I feel that would annoy users.
Thank you in adv for any help. Here's the page in question: http://nicpadula.com/brand-design
<script>
$(function() {
$("body").mousewheel(function(event, deltaY) {
if (deltaY > 0){
$(document).ready(function()
{
$("div.arrow-wrapper.left").click();
});
}
else if (deltaY < 0){
$(document).ready(function()
{
$("div.arrow-wrapper.right").click();
});
}
});
});
</script>

How to make Bootstrap header that changes size on scroll down?

I've seen a few different threads seemingly about this but none of the answers in them have a working solution for me.
Here's what I want:
Big transparent header with a big logo on the top.
Small colored header with a small logo when user has scrolled past the topmost area.
I'm using navbar-fixed-top and and Bootstrap's scrollspy to add and remove certain classes from the header.
Here's why it hasn't worked so far:
$(window).scrollTop() doesn't return anything meaningful at all.
It seems wrong to change at a certain amount of pixels from the top anyway, since it can vary between screen resolutions.
Initiating a change based on what activate.bs.scrollspy captures works rather well except it shows the wrong header when I load the page for the first time.
It seems impossible to place a <div id="whatever"> at a certain spot and have the header change when scrollspy finds it. I've tried making the div 1px in dimension and placed at the absolute top of the page, but the scrollspy still identifies it from way off.
Here's my jQuery code at the moment, which is very imprecise AND shows the wrong header at the first load of the page (remember, you're not always at the top of the page when loading (reloading) the page!).
$(document).ready(function() {
$('body').scrollspy({ target: '.navbar-inverse' });
$('#main-header').on('activate.bs.scrollspy', function () {
var currentItem = $('.nav li.active > a').text();
var header = $('.navbar');
var logosmall = $('.small-brand');
var logobig = $('.big-brand');
if (currentItem == 'top' && header.hasClass('navbar-small')) {
header.removeClass('navbar-small');
header.addClass('navbar-big');
logosmall.css('display', 'none');
logobig.css('display', 'inline-block');
}
else if (currentItem != 'top' && header.hasClass('navbar-big')) {
header.removeClass('navbar-big');
header.addClass('navbar-small');
logobig.css('display', 'none');
logosmall.css('display', 'inline-block');
}
});
});

Wrap your code into window scroll event as mentioned below then only $(window).scrollTop() will work as you expecting.
$(window).scroll(function () {});

Here is a great example of your problem, it is a bit tricky to shrink your navbar but not impossible. You have to take into account a lot of things. I found this a while ago: http://www.bootply.com/109943
It is really strange that $(window).scrollTop() does not return anything by the way. What browser are you on? And your problem with reloading the browser:
$(window).load(function{
//logic to check how far scrolled
})

Scroll to link with skrollr

I am using https://github.com/Prinzhorn/skrollr to animate the background of my site as I scroll. However I am also wanting to have my links scroll up and down the page like a normal single page site would do.
The problem is that both are working if I manually scroll the background changes, if I click the link the page scrolls to the correct place. The problem is that when I click the button the background doesn't scroll as well.
It seems like I am working with two different scroll functions and as a result they aren't working together and I need to use the same one.
Here is the code.
js - Scroll to link:
var $root = $('html, body');
$('a').click(function() {
var href = $.attr(this, 'href');
$root.animate({
scrollTop: $(href).offset().top
}, 500, function () {
window.location.hash = href;
});
return false;
});
js – Skrollr init
skrollr.init({
smoothScrolling: true,
forceHeight: true
});
I will try put together a fiddle to make it more clear but hopefully the answer is really simple.

If anyone else ever faces this problem the answer lies her: https://github.com/Prinzhorn/skrollr-menu
This will allow you to scroll to you internal links along with Skrollr animations. A HUGE plus and a very simple fix, you don't even need any of your own scrolling code just this and it will work with you links.

There's a way to do this, Skrollr has some methods very useful, in console, just type the variable contains skrollr, it will show some methods that you can use, one of them is "setScrollTop(int, bool)", so just call this method with the info you need, for example:
s.setScrollTop(9000, true)
Which means that I want it to scroll to the height position 9000. It works fine, you just need to know the height position where you need to go.

Animate a div after scrolling away from the top of the webpage

I'm currently trying to make a div appear from behind another div after the user scrolls away from the top of the page.
I'm hoping to do this using animate so that it slides out. Like this...
http://jsfiddle.net/xaYTt/99/
But I can't figure out how to make the red box stay behind the blue box until the user scrolls away from the top of the page.
I also need to reverse this when the user scrolls back up to the top of the page, so the red box slides back under the blue box again.
Can anyone help me out?

This is not the most elegant solution, but it works nonetheless.
http://jsfiddle.net/37LZ5/
Components:
Use $(document).scroll as a trigger to know when scrolling
Use scrollTop() to know how far we're scrolling (0 = top)
Remember state to make sure animation doesn't get triggered a zillion times (var away)
Use .stop() to prevent weird behaviour when halfway through one animation, another animation gets triggered

I think you are looking for this take a look at this demo
Working demo
Code
$(document).ready(function(){
//$('#bottom-box').animate({'margin-top': '200px'}, 1500);
$('body').hover(function(){
$('#bottom-box').animate({'margin-top': '200px'}, 1500);
}, function(){
$('#bottom-box').animate({'margin-top': '50px'}, 1500);
});
});

If my understanding about your question is correct, this is what you are looking for
Since you said, "User scrolls away from the top of the page", I added a div to be at the top of the page.
var isAlreadyOut=false;
$("#divPageTop").mouseover(function(){
if( isAlreadyOut==true)
{
$('#bottom-box').animate({'margin-top': '60px'}, 1500);
isAlreadyOut=false;
}
else
{
$('#bottom-box').animate({'margin-top': '200px'}, 1500);
isAlreadyOut=true;
}
});
Here is the jsfiddle version
http://jsfiddle.net/xaYTt/103/

I did something with jsFiddle that might be what you are after, if I understood your question correctly.
Basically, the red box will animate when you scroll the window more than the distance of the blue box.
Not 100%, just a quick mock up to see if that's what you want.
(When you scroll, click on the scroll bar arrows for more accurate results)
Demo here: http://jsfiddle.net/peduarte/xaYTt/104/