We Keep Coding

How do I get this JS code from Codepen to work?

Here is the link to codepen: https://codepen.io/rishabhp/pen/aNXVbQ?limit=all&page=7&q=navigation+bar
I am using Brackets and created a html,css,js file. Everything seems to be working except for the js. I've linked the css and js files on the head section. Do I somehow have to link something else or download an extra file?
Head tag looks like this:
<link type="text/css" rel="stylesheet" href="style.css" />
<script src="theFile.js"></script>
HTML code:
<nav>
<ul>
<li>First</li>
<li>Second</li>
<li>Third</li>
<li>Fourth</li>
<li>Fifth</li>
</ul>
</nav>
<div class="sections">
<section id="1"><h1>First</h1></section>
<section id="2"><h1>Second</h1></section>
<section id="3"><h1>Third</h1></section>
<section id="4"><h1>Fourth</h1></section>
<section id="5"><h1>Fifth</h1></section>
</div>
<footer></footer>
<script class="cssdeck" src="//cdnjs.cloudflare.com/ajax/libs/jquery/1.8.0/jquery.min.js"></script>
CSS code:
#import url(https://fonts.googleapis.com/css?family=Open+Sans);
* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
body {
font-family: 'Open Sans', sans-serif;
}
/* Navigation */
nav {
width: 100%;
height: 60px;
position: fixed;
top: 0;
background: #1ABC9C;
}
nav ul {
padding: 20px;
margin: 0 auto;
list-style: none;
text-align: center;
}
nav ul li {
display: inline-block;
margin: 0 10px;
}
nav ul li a {
padding: 10px 0;
color: #fff;
font-size: 1rem;
text-decoration: none;
font-weight: bold;
transition: all 0.2s ease;
}
nav ul li a:hover {
color: #34495E;
}
a.active {
border-bottom: 2px solid #ecf0f1;
}
/* Headings */
h1 {
font-size: 5rem;
color: #34495E;
}
/* Sections */
section {
width: 100%;
padding: 50px;
background: #fff;
border-bottom: 1px solid #ccc;
height: 500px;
text-align: center;
}
section:nth-child(even) {
background: #ecf0f1;
}
section:nth-child(odd) {
background: #bdc3c7;
}
.sections section:first-child {
margin-top: 60px;
}
section.active {}
footer {
height: 500px;
background: #34495e;
}
JS code:
var sections = $('section')
, nav = $('nav')
, nav_height = nav.outerHeight();
$(window).on('scroll', function () {
var cur_pos = $(this).scrollTop();
sections.each(function() {
var top = $(this).offset().top - nav_height,
bottom = top + $(this).outerHeight();
if (cur_pos >= top && cur_pos <= bottom) {
nav.find('a').removeClass('active');
sections.removeClass('active');
$(this).addClass('active');
nav.find('a[href="#'+$(this).attr('id')+'"]').addClass('active');
}
});
});
nav.find('a').on('click', function () {
var $el = $(this)
, id = $el.attr('href');
$('html, body').animate({
scrollTop: $(id).offset().top - nav_height
}, 500);
return false;
});

You have to include your JavaScript files after including the jquery.min.js. Otherwise your code gets executed before jQuery is initialized.
Remove <script src="theFile.js"></script> in the head tag and add it at the very bottom of your HTML.
<nav>
<ul>
<li>First</li>
<li>Second</li>
<li>Third</li>
<li>Fourth</li>
<li>Fifth</li>
</ul>
</nav>
<div class="sections">
<section id="1"><h1>First</h1></section>
<section id="2"><h1>Second</h1></section>
<section id="3"><h1>Third</h1></section>
<section id="4"><h1>Fourth</h1></section>
<section id="5"><h1>Fifth</h1></section>
</div>
<footer></footer>
<script class="cssdeck" src="//cdnjs.cloudflare.com/ajax/libs/jquery/1.8.0/jquery.min.js"></script>
<script src="theFile.js"></script>
You can check your console (shortcut: F12), there should be a error like
$ is not defined
in the console.
Edit:
You can ensure jQuery is initialized when your code is executed by waiting to load the page completely. You just have to wrap your code with $(document).ready() function.
$(document).ready(function(){
var sections = $('section')
, nav = $('nav')
, nav_height = nav.outerHeight();
$(window).on('scroll', function () {
var cur_pos = $(this).scrollTop();
sections.each(function() {
var top = $(this).offset().top - nav_height,
bottom = top + $(this).outerHeight();
if (cur_pos >= top && cur_pos <= bottom) {
nav.find('a').removeClass('active');
sections.removeClass('active');
$(this).addClass('active');
nav.find('a[href="#'+$(this).attr('id')+'"]').addClass('active');
}
});
});
nav.find('a').on('click', function () {
var $el = $(this)
, id = $el.attr('href');
$('html, body').animate({
scrollTop: $(id).offset().top - nav_height
}, 500);
return false;
});
});

jQuery detect div location on scroll

I'm new to jQuery and am struggling with making the jQuery detect the location of div .stage-O so that when scrolling down the .header doesn't disappear until the bottom of that .stage-O hits the top of the page?
jQuery(document).ready(function () {
var lastFixPos = 0,
threshold = 100, //sensitivity on scrolling
$header = $('.header');
$(window).on('scroll', function() {
var st = $(this).scrollTop();
var diff = Math.abs($(window).scrollTop() - lastFixPos);
if (diff > threshold || st < 100) {
if (st < lastFixPos) {
// scroll up
$header.removeClass('hide').addClass('color headerBGchange headerLIchange');
}
lastFixPos = st;
} else if (st > lastFixPos) {
//scroll down
$header.addClass('hide').removeClass('color');
}
});
$(window).scroll(function(e) {
var sw = $('.header'),
pg = $('.stage-2'),
diff = pg[0].offsetbottom - window.pageYOffset;
sw.css('background-color', diff < 100 ? 'white' : '');
});
});
.header {
display: -webkit-box;
display: -webkit-flex;
display: -ms-flexbox;
display: flex;
-webkit-box-align: center;
-webkit-align-items: center;
-ms-flex-align: center;
align-items: center;
height: 80px;
-webkit-transition: top 250ms ease;
transition: top 250ms ease;
position: fixed;
width: 100%;
top: 0;
background-color: transparent;
overflow: hidden;
}
.header ul {
margin: 20px;
padding: 0;
}
.header ul li {
display: inline-block;
margin-right: 20px;
color: green;
}
.header ul li:last-child {
margin-right: 0;
}
.hide {
top: -80px;
}
.headerBGchange{
Background: white;
}
.headerLIchange{
color: Blue;
}
.stage {
color: #fff;
display: -webkit-box;
display: -webkit-flex;
display: -ms-flexbox;
display: flex;
-webkit-box-pack: center;
-webkit-justify-content: center;
-ms-flex-pack: center;
justify-content: center;
-webkit-box-align: center;
-webkit-align-items: center;
-ms-flex-align: center;
align-items: center;
height: 100vh;
background-color: bisque;
font-size: 48px;
}
.stage-0 {
background: black;
}
.stage-1 {
background: #030202;
}
.stage-2 {
background: #060505;
}
.stage-3 {
background: #080707;
}
.stage-4 {
background: #0b0a09;
}
.stage-5 {
background: #0e0c0b;
}
.stage-6 {
background: #110e0e;
}
.stage-7 {
background: #141110;
}
.stage-8 {
background: #161312;
}
.stage-9 {
background: #191515;
}
.stage-10 {
background: #1c1817;
}
.stage-11 {
background: #1f1a19;
}
.stage-12 {
background: #221d1c;
}
.stage-13 {
background: #241f1e;
}
.stage-14 {
background: #272120;
}
.stage-15 {
background: #2a2422;
}
.stage-16 {
background: #2d2625;
}
.stage-17 {
background: #302827;
}
.stage-18 {
background: #322b29;
}
.stage-19 {
background: #352d2c;
}
.stage-20 {
background: #38302e;
}
.stage-21 {
background: #3b3230;
}
.stage-22 {
background: #3e3432;
}
.stage-23 {
background: #413735;
}
.stage-24 {
background: #433937;
}
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
<div class="header">
<ul>
<li>Home</li>
<li>About</li>
<li>Contact</li>
</ul>
</div>
<div class="stage stage-0">1</div>
<div class="stage stage-2">3</div>
<div class="stage stage-4">5</div>
<div class="stage stage-6">7</div>
<div class="stage stage-8">9</div>
<div class="stage stage-10">11</div>
<div class="stage stage-12">13</div>
<div class="stage stage-14">15</div>
<div class="stage stage-16">17</div>
<div class="stage stage-18">19</div>
<div class="stage stage-20">21</div>
<div class="stage stage-22">23</div>

Is this what you are looking for? I changed the code quite a bit because it seemed like yours was a little overly complicated. Not sure why you were attaching two scroll events. Also I just added a red border to the stage class so you could clearly see when we were passing the bottom of it.
Fiddle: http://jsfiddle.net/AtheistP3ace/4hs7n0Lq/
var lastScrollTop = 0;
$(window).on('scroll', function() {
var header = $('.header');
var stage0 = $('.stage-0');
var scrollTop = $(window).scrollTop();
if (scrollTop > lastScrollTop) {
// down scroll
if (scrollTop > stage0.offset().top + stage0.height()) {
header.addClass('hide').removeClass('color');
}
} else {
// up scroll
if (scrollTop <= stage0.offset().top + stage0.height()) {
header.removeClass('color headerBGchange headerLIchange');
} else {
header.removeClass('hide').addClass('color headerBGchange headerLIchange');
}
}
lastScrollTop = scrollTop;
});
It simply tracks the lastScroll to determine if we are going up or down. If we are going down lets check if we have passed the stage0 div by getting its offset plus its height (the bottom of it). If we are scrolling up lets see if we are above the bottom of the stage0 div, if not we are scrolling up but have not reached it yet.
As to your question about the text color its not working because you set the color on the header which would cascade down but you also have this:
.header ul li {
display: inline-block;
margin-right: 20px;
color: green;
}
Which is a more specific selector so it overrides the higher one. So instead of
.headerLIchange {
color: Blue;
}
do
.header.headerLIchange ul li {
color: Blue;
}
Fiddle: http://jsfiddle.net/AtheistP3ace/4hs7n0Lq/1/

This might help you:
<body onload="document.getElementById('scrollBox').scrollTop = document.getElementById('scrollPosition').value;">
<input type="hidden" id="scrollPosition" />
<div id="scrollBox" style="overflow:scroll;height:100px;width:150px;" onscroll="javascript:document.getElementById('scrollPosition').value = this.scrollTop">
...content goes here...
...more content...
...link goes here...
</div>
</body>
Ref: http://www.quackit.com/html/codes/div_scroll_position.cfm

Move to specific div based on button click

I was trying to move the divs (here it's question number) based on the prev and next button. So that the selected question is always visible on screen.
Here is the demo : http://jsfiddle.net/arunslb123/trxe4n3u/12/
Screen :
click and question number and click prev or next button to understand my issue.
My code :
$("#next")
.click(function () {
$(".c.current-question")
.each(function () {
var divIdx = $(this)
.attr('id');
var scrollTo = $('#' + divIdx)
.position()
.left;
$("#scrollquestion")
.animate({
'scrollLeft': scrollTo
}, 800);
});
});
$("#prev")
.click(function () {
$(".c.current-question")
.each(function () {
var divIdx = $(this)
.attr('id');
var scrollTo = $('#' + divIdx)
.position()
.left;
$("#scrollquestion")
.animate({
'scrollLeft': -scrollTo
}, 800);
});
});

Using scrollLeft is a bit tricky. I did a small redo of your use-case based on positioning and then moving it based on left of the container. The tricky part is to reliably calculate the negative position when scrolled to the extreme right. Also, need to take into account the widths and margins.
Check the below snippet:
var $wrap = $("#numWrap"), $strip = $("#strip"),
$leftArrow = $(".wrapper > .arrows").first(),
wrapWidth = $wrap.width() + $leftArrow.width(),
margin = 10;
fill(20); select($(".numberItem").first());
$strip.on("click", ".numberItem", function() { select($(this)); });
function select($elem) {
$(".numberItem").removeClass("selected");
$elem.addClass("visited").addClass("selected");
focus($elem[0]);
}
function focus(elem) {
var stripPos = $strip.position(),
numPos = $(elem).offset(),
elemWidth = $(elem).width() + margin,
numRight = numPos.left + elemWidth;
if (numRight > wrapWidth) {
$strip.css({"left": stripPos.left - elemWidth});
}
if (numPos.left < (margin + $leftArrow.width())) {
$strip.css({"left": stripPos.left + elemWidth});
}
}
$(".wrapper").on("click", "a.arrow", function() {
var stripPos = $strip.position();
if (this.id == "lft") {
$strip.css({"left": stripPos.left + (wrapWidth / 2)});
} else {
$strip.css({"left": stripPos.left - (wrapWidth / 2)});
}
});
$(".controls").on("click", "a.arrow", function() {
var $sel = $(".selected"), numPos, $sel, elemWidth;
$elem = $sel.length > 0 ? $sel.first() : $(".numberItem").first();
if (this.id == "lft") {
$sel = $elem.prev().length > 0 ? $elem.prev() : $elem;
select($sel);
} else {
$sel = $elem.next().length > 0 ? $elem.next() : $elem;
select($sel);
}
numPos = $sel.offset(); elemWidth = $sel.width() + margin;
numRight = numPos.left + elemWidth;
if (numPos.left > wrapWidth) {
$strip.css({"left": -($sel.text()) * $sel.width() });
}
if (numRight < 0) {
$strip.css({"left": +($sel.text()) * $sel.width() });
}
});
function fill(num){
for (var i = 1; i <= num; i++) {
var $d = $("<a href='#' class='numberItem'>" + i + "</a>");
$strip.append($d);
}
}
* { box-sizing: border-box; padding: 0; margin: 0; font-family: sans-serif; }
div.wrapper {
background-color: #ddd; width: 100vw; height: 64px;
clear: both; overflow: hidden; margin-top: 16px;
}
div.arrows {
float: left; width: 10%; min-width: 24px; height: 64px; line-height: 64px;
text-align: center; vertical-align: middle; overflow: hidden;
}
div.numWrap {
float: left; height: 64px; line-height: 64px;
width: 80%; vertical-align: middle;
overflow: hidden; position: relative;
}
div.strip {
position: absolute; left: 0px;
width: auto; white-space: nowrap;
transition: left 1s;
}
a.numberItem {
display: inline-block; text-align: center; margin: 0px 8px;
background-color: #fff; border-radius: 50%; width: 48px; height: 48px;
font-size: 1.2em; line-height: 48px; text-decoration: none;
}
a.numberItem.visited { background-color: #fff; color: #000; border: 2px solid #01aebc; }
a.numberItem.selected { background-color: #01aebc; color: #fff; }
div.controls { clear: both; }
div.controls > div.arrows { width: auto; margin: 0 12px; }
a, a:focus, a:active, a:link, a:visited {
display: inline-block;
text-decoration: none; font-weight: 600;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="wrapper">
<div class="arrows">
<a id="lft" class="arrow" href="#">〈</a>
</div>
<div id="numWrap" class="numWrap">
<div id="strip" class="strip"></div>
</div>
<div class="arrows">
<a id="rgt" class="arrow" href="#">〉</a>
</div>
</div>
<div class="controls">
<div class="arrows">
<a id="lft" class="arrow" href="#">〈 Previous</a>
</div>
<div class="arrows">
<a id="rgt" class="arrow" href="#">Next 〉</a>
</div>
<div>
Explanation:
Using absolute positioning on the number container, which is nested to get 100% width.
Markup:
<div class="wrapper">
<div class="arrows"><a id="lft" class="arrow" href="#">〈</a></div>
<div id="numWrap" class="numWrap">
<div id="strip" class="strip"></div> <!-- nesting here -->
</div>
<div class="arrows"><a id="rgt" class="arrow" href="#">〉</a></div>
</div>
CSS:
div.wrapper {
background-color: #ddd; width: 100vw; height: 64px;
clear: both; overflow: hidden; margin-top: 16px;
}
div.arrows {
float: left; width: 10%; min-width: 24px; height: 64px; line-height: 64px;
text-align: center; vertical-align: middle; overflow: hidden;
}
div.numWrap {
float: left; height: 64px; line-height: 64px;
width: 80%; vertical-align: middle;
overflow: hidden; position: relative; /* relatively positioned */
}
div.strip {
position: absolute; left: 0px; /* absolutely positioned */
width: auto; white-space: nowrap;
transition: left 1s; /* instead of jquery animate */
}
With this structure, we can now use left to control the scrolling.
For partially obscured numbers, try to gently focus-in (nudge into view) a number which is partially obscured. This can be done by checking the position relative to parent and adding the width/margin to it and also accounting for width of the left arrow (it might peep thru).
Javascript:
function focus(elem) {
var stripPos = $strip.position(),
numPos = $(elem).offset(),
elemWidth = $(elem).width() + margin,
numRight = numPos.left + elemWidth;
// if it is towards right side, nudge it back inside
if (numRight > wrapWidth) {
$strip.css({"left": stripPos.left - elemWidth});
}
// if it is towards left side, nudge it back inside
if (numPos.left < (margin + $leftArrow.width())) {
$strip.css({"left": stripPos.left + elemWidth});
}
}
Once the user has scrolled the list too far and then tries to click on previous / next buttons to select a question, then we need to move the entire container upto the selected number. We can easily do this by multiplying the question number with element width and then changing the left in positive (if towards right) or in negative (if towards left).
Javascript:
// if left of element is more than the width of parent
if (numPos.left > wrapWidth) {
$strip.css({"left": -($sel.text()) * $sel.width() });
}
// if right of element is less than 0 i.e. starting position
if (numRight < 0) {
$strip.css({"left": +($sel.text()) * $sel.width() });
}
Here is a fiddle to play with: http://jsfiddle.net/abhitalks/aw166qhx/
You will need to further adapt it to your use-case, but you get the idea.

Hold ul visible when parent loses hover (pure css if possible)

I'm quite new with css. I want hold the ul visible when hovering from parent to ul. I don't know how do it.
HTML Markup
<drop-down class="dropdown">
<span>Dropdown menu<i class="fa fa-cog"></i></span>
<ul>
<li>
Github<i class="fa fa-github"></i>
</li>
<li>
BitBucket<i class="fa fa-bitbucket"></i>
</li>
<li>
Dropbox<i class="fa fa-dropbox"></i>
</li>
<li>
Google drive<i class="fa fa-google"></i>
</li>
</ul>
</drop-down>
CSS
drop-down {
background-color: #e9e9e9;
border: 1px solid #d2c2c2;
border-radius: 2px;
display: flex;
flex-flow: column nowrap;
height: 40px;
justify-content: center;
position: relative;
width: 160px;
}
drop-down:hover { cursor: pointer; }
drop-down > span {
align-items: center;
color: #555;
display: flex;
font-family: 'segoe ui';
font-size: .9rem;
justify-content: space-between;
padding: 0px .75rem;
pointer-events: none;
}
drop-down > span > i {
color: inherit;
}
drop-down ul {
background-color: #e9e9e9;
border: 1px solid #d2c2c2;
border-radius: 2px;
box-shadow: 0px 2px 5px 1px rgba(0,0,0,.15);
display: block;
right: 10%;
list-style: none;
padding: .5rem 0;
position: absolute;
opacity: 0;
pointer-events: none;
visibility: hidden;
top: 160%;
transition: all .2s ease-out;
width: 100%;
z-index: 999;
}
drop-down ul > li {
color: #555;
display: block;
}
drop-down ul > li:hover {
background-color: #007095;
color: rgba(255,255,255,.9);
}
drop-down ul > li > a {
align-items: center;
color: inherit;
display: flex;
font-family: 'segoe ui';
font-size: .95rem;
justify-content: space-between;
padding: .5rem .75rem;
text-decoration: none;
}
drop-down ul > li > a > i {
color: inherit;
}
drop-down:focus {
outline: none;
}
drop-down:hover ul {
pointer-events: auto;
opacity: 1;
top: 120%;
visibility: visible;
}
You can see it running at this fiddle: http://jsfiddle.net/vt1y9ruo/1/
I can do it with javascript, but I don't want use it for something small.

Here's a working fiddle: http://jsfiddle.net/vt1y9ruo/8/
It works by inserting an invisible bridge between the button and the list.
drop-down:hover ul, #ulwrap:hover ul {
pointer-events: auto;
opacity: 1;
top:120%;
visibility: visible;
}
#ulwrap {
display: block;
height:0;
width:100%;
position:absolute;
}
drop-down:hover #ulwrap, #ulwrap:hover {
height:100px;
}

if you want to do this using the hover feature of css, the gap between the button and the list is what's killing you. either remove this gap or use js
on a side note there is no harm in using js for something small, this is what its used for, just make it nice and reusable

Well, pure css solution (many thanks #JBux) is a little dirty (mark up). I finally go for JS solution and for this, created a custom tag:
const helper = new Helper(); // helper functions
var ddProto = Object.create(HTMLElement.prototype);
ddProto.properties = {
list: null,
options: null,
value: null,
icon: null,
index: -1,
};
ddProto.initEvents = function() {
var self = this;
// mouse over button
this.addEventListener('mouseover', function(e) {
if(!helper.hasClass(this, 'dropdown-active'))
helper.addClass(this, 'dropdown-active');
});
// mouseleave over button
this.addEventListener('mouseleave', function(e){
var rect = this.getBoundingClientRect();
var left = e.pageX;
var bottom = e.pageY;
// if mouse is out of X axis of button and if mouse is
// out (only of top) of Y axis of button, hide ul
if(left < rect.left || left >= rect.right || bottom < rect.top) {
helper.delClass(this, 'dropdown-active');
}
});
// list loses hover
this.properties.list.addEventListener('mouseleave', function(e) {
if(helper.hasClass(self, 'dropdown-active'))
helper.delClass(self, 'dropdown-active');
});
// elements click
[].forEach.call(this.properties.options, function(e) {
e.addEventListener('click', function(event){
event.preventDefault();
// set the text of selected value to button
helper.text(self.properties.value, e.innerText);
// set the position of selected value
self.properties.index = helper.position(e.parentNode);
// set the <i> class name to the button (fontawesome)
self.properties.icon.className = this.children[0].className;
// hide ul
helper.delClass(self,'dropdown-active');
},true);
});
};
ddProto.value = function() {
return this.properties.value;
};
ddProto.index = function() {
return this.properties.index;
}
ddProto.createdCallback = function() {
this.properties.list = this.querySelector('ul');
this.properties.options = this.querySelectorAll('ul > li > a');
this.properties.value = this.querySelector('span');
this.properties.icon = this.querySelector('span > i');
this.initEvents();
};
document.registerElement('drop-down', {prototype: ddProto});
Working fiddle: http://jsfiddle.net/m2dtmr24/2/
Thank you so much.

The thing you could check is the + selector (more here)
In short it lets you add styles to elements right next to each other. The actual css might look something like this:
.dropdown{
display: none;
}
.button:hover+.dropdown{
display: block;
}
This will only work when .dropdown is directly below .button in the DOM
The animation might be harder, but you could achieve something similar by for example using transition on opacity, and toggle opacity instead of display

adding more button for list in responsive navigation

I have a navigation of lets say 12 items, and when resolution gets smaller items drop in a new line. I need to make that when an item doesn't fit on a navigation anymore it should put a "MORE" dropdown button on the right side of nav. and put that item that doesn't fit in a dropdown.
If you don't understand me there is image below.
But the problem is that navigation items aren't always the same width because navigation items are generated from REST api.
I tryed to make jQuery script for calculating items width and adding them to navigation.
Here is the script I created, I made it in a hurry so it's really bad.
I need to help on how to properly calculate items witdh and navigation width and calculating when to add items to navigation or remove items from navigation.
Here is image if you don't get it: http://img.hr/aagV
/*
* Here we check how many items can we put on the navigation bar
* If item doesn't fit we clone it on the more dropdown button
*/
function removeMany() {
var i = $items.length - 1;
if (itemsWidth > navWidth) {
while (itemsWidth > navWidth) {
$($items[i]).removeClass('first-level-item').addClass('second-level-item');
dropdownItems.push($items[i]);
$($items[i]).removeClass('showed');
$items.pop();
i--;
getItemsWidth();
}
$nav.append($navMore);
dropdownItems.reverse().forEach(function (element, index, array) {
$('ul.second-level').append(element);
});
getItems();
}
}
//If window is resized to bigger resolution we need to put back items on the navbar
function addMany() {
var i = dropdownItems.length - 1;
if (dropdownItems.length != 0) {
do {
$('ul.first-level').append(dropdownItems.reverse()[i]);
$items.push(dropdownItems[i]);
dropdownItems.pop();
i--;
getItemsWidth();
} while (itemsWidth < navWidth);
$navMore.remove();
$items.each(function (i) {
$(this).addClass('first-level-item showed').removeClass('second-level-item');
});
if (!(dropdownItems != 0)) {
return;
} else {
$nav.append($navMore);
}
}
}
body {
margin: 0;
padding: 0;
border: 0; }
ul, li {
margin: 0;
padding: 0;
list-style: none; }
ul.second-level li {
display: block !important; }
ul.second-level li > a {
color: black; }
a {
color: #fff;
text-decoration: none;
text-transform: uppercase; }
.second-level-item a {
color: #333 !important; }
.navigation {
width: 960px;
max-width: 100%;
background: #211;
color: #aaa;
margin: 0 auto; }
.first-level .first-level-item {
display: inline-block;
padding: 10px; }
.first-level .item-more {
display: inline-block; }
.first-level .item-more .second-level-item {
display: inline-block; }
.second-level {
position: absolute;
top: 100%;
right: 0;
width: 200px;
background: #fff;
padding: 10px;
box-shadow: 0 4px 10px rgba(0, 0, 0, 0.4); }
.has-second-level {
position: relative; }
.has-second-level .second-level {
display: none; }
.has-second-level:hover {
background: #fff;
color: #000; }
.has-second-level:hover .second-level {
display: block; }
/*# sourceMappingURL=style.css.map */
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>DropDown</title>
<link rel="stylesheet" href="css/reset.css"/>
<link rel="stylesheet" href="css/style.css"/>
</head>
<body>
<nav class="navigation">
<ul class="first-level">
<li class="first-level-item showed">Introduction to Irish Culture</li>
<li class="first-level-item showed">Cellular and Molecular Neurobiology</li>
<li class="first-level-item showed">Guitar foundations</li>
<li class="first-level-item showed">Startup Inovation</li>
<li class="first-level-item showed">Astrophysics</li>
<li class="first-level-item item-more has-second-level">
<span> More </span>
<ul class="second-level">
</ul>
</li>
</ul>
</nav>
<script src="https://code.jquery.com/jquery-2.1.1.js"></script>
</body>
</html>

If you have fixed-width list-items, then it is simple to collect extra list-items and push them into a separate list. Here is a simple example. Explanation is in the code comments.
View the snippet in full-screen and try changing the window width.
Also a Fiddle: http://jsfiddle.net/abhitalks/860LzgLL/
Full Screen: http://jsfiddle.net/abhitalks/860LzgLL/embedded/result/
Snippet:
var elemWidth, fitCount, fixedWidth = 120,
$menu = $("ul#menu"), $collectedSet;
// Assuming that the list-items are of fixed-width.
collect();
$(window).resize(collect);
function collect() {
// Get the container width
elemWidth = $menu.width();
// Calculate how many list-items can be accomodated in that width
fitCount = Math.floor(elemWidth / fixedWidth) - 1;
// Create a new set of list-items more than the fit count
$collectedSet = $menu.children(":gt(" + fitCount + ")");
// Empty the collection submenu and add the cloned collection set
$("#submenu").empty().append($collectedSet.clone());
}
* { box-sizing: border-box; margin: 0; padding: 0; }
div { position: relative; background-color: #ccc; height: 32px; overflow: visible; }
ul#menu, ol { height: 32px; max-width: 80%; overflow: hidden; }
ul#menu > li, ol > li { display: block; float: left; height: 32px; width: 120px; padding: 4px 8px; }
ol { position: absolute; right: 0; top: 0; overflow: visible; }
ol > li { min-width: 120px; }
ol ul { position: absolute; top: 120%; right: 10%; }
ol li ul > li { list-style: none; background-color: #eee; border: 1px solid gray; padding: 4px 8px;}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div>
<ul id="menu">
<li>Option One</li><li>Option Two</li><li>Option Three</li>
<li>Option Four</li><li>Option Five</li><li>Option Six</li>
</ul>
<ol><li>Collected<ul id="submenu"></ul></li></ol>
</div>
Update:
This is regarding your query on differing / variable widths of list-items. There would be a minor change.
Also a Fiddle: http://jsfiddle.net/abhitalks/tkbmcupt/1/
Full Screen: http://jsfiddle.net/abhitalks/tkbmcupt/1/embedded/result/
Snippet:
var elemWidth, fitCount, varWidth = 0, ctr, $menu = $("ul#menu"), $collectedSet;
// Get static values here first
ctr = $menu.children().length; // number of children will not change
$menu.children().each(function() {
varWidth += $(this).outerWidth(); // widths will not change, so just a total
});
collect(); // fire first collection on page load
$(window).resize(collect); // fire collection on window resize
function collect() {
elemWidth = $menu.width(); // width of menu
// Calculate fitCount on the total width this time
fitCount = Math.floor((elemWidth / varWidth) * ctr) - 1;
// Reset display and width on all list-items
$menu.children().css({"display": "block", "width": "auto"});
// Make a set of collected list-items based on fitCount
$collectedSet = $menu.children(":gt(" + fitCount + ")");
// Empty the more menu and add the collected items
$("#submenu").empty().append($collectedSet.clone());
// Set display to none and width to 0 on collection,
// because they are not visible anyway.
$collectedSet.css({"display": "none", "width": "0"});
}
* { box-sizing: border-box; margin: 0; padding: 0; }
div { position: relative; background-color: #ccc; height: 32px; overflow: visible; }
ul#menu, ol { height: 32px; max-width: 80%; overflow: hidden; }
ul#menu > li, ol > li { display: block; float: left; height: 32px; white-space: nowrap; padding: 4px 8px; }
ol { position: absolute; right: 0; top: 0; overflow: visible; }
ol > li { min-width: 120px; }
ol ul { position: absolute; top: 120%; right: 10%; }
ol li ul > li { list-style: none; background-color: #eee; border: 1px solid gray; padding: 4px 8px;}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div>
<ul id="menu">
<li>Option One</li><li>Option Two</li><li>Option Three</li>
<li>Option Four</li><li>Option Five</li><li>Option Six</li>
</ul>
<ol><li>Collected<ul id="submenu"></ul></li></ol>
</div>

Can and SHOULD be optimised (as it is quite inefficient from what i've tested), but that's up to you.
$(document).ready(function(){
var moreW = $(".more").outerWidth(), //width of your "more" element
totalW = -moreW, //cumulated width of list elements
totalN = $('.nav li').length - 1, //number of elements minus the "more" element
dw = document.documentElement.clientWidth;
$('.nav li').each(function(){
totalW += $(this).outerWidth();
});
function moveToDropdown(){
dw = document.documentElement.clientWidth;
//moves elements into the list
while(totalW > (dw - moreW)){
var temp = $(".nav li:nth-last-child(2)"); //element to be moved
totalW = totalW - temp.outerWidth();
$(".dropdown").append(temp.clone());
temp.remove();
}
//moves elements out of the list
var newList = $('.dropdown li').length; //check if we have elements
if(newList > 0){
var element = $('.dropdown li:last-child'), //element to be moved
elementW = $('.dropdown li:last-child').outerWidth(); //width of element to be moved
if(totalW + elementW < dw - moreW){
while(totalW + elementW < dw - moreW ){
var element = $('.dropdown li:last-child'),
elementW = $('.dropdown li:last-child').outerWidth();
totalW = totalW + elementW;
$(".nav > li:last-child").before(element.clone());
element.remove();
}
}
}
}
moveToDropdown();
$(window).resize(moveToDropdown)
});
.clearfix:after{
display:block;
content:'';
clear:both;
}
body,html{
width:100%;
height:100%;
margin:0;
padding:0;
}
ul{
list-style:none;
width:100%;
padding:0;
margin:0;
}
ul li{
float:left;
padding:5px;
}
.nav > li {
position:relative;
}
.nav ul{
position:absolute;
top:25px;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<ul class="nav clearfix">
<li>Item</li>
<li>Item</li>
<li>Item</li>
<li>Item</li>
<li>Item</li>
<li>Item</li>
<li>Item</li>
<li class="more">
more
<ul class="dropdown">
<!-- we'll add elements here -->
</ul>
</li>
</ul>

This question is too old, but i want to post my answer too. Maybe this is more cleaner and easier way. I have created a pen: https://codepen.io/sergi95/pen/bmNoML
<div id="mainMenu" class="main-menu">
<ul id="autoNav" class="main-nav">
<li>
home
</li>
<li>
about us
</li>
<li>
portfolio
</li>
<li>
team
</li>
<li>
blog
</li>
<li>
contact
</li>
<li id="autoNavMore" class="auto-nav-more">
more
<ul id="autoNavMoreList" class="auto-nav-more-list">
<li>
policy
</li>
</ul>
</li>
</ul>
const $mainMenu = $("#mainMenu");
const $autoNav = $("#autoNav");
const $autoNavMore = $("#autoNavMore");
const $autoNavMoreList = $("#autoNavMoreList");
autoNavMore = () => {
let childNumber = 2;
if($(window).width() >= 320) {
// GET MENU AND NAV WIDTH
const $menuWidth = $mainMenu.width();
const $autoNavWidth = $autoNav.width();
if($autoNavWidth > $menuWidth) {
// CODE FIRES WHEN WINDOW SIZE GOES DOWN
$autoNav.children(`li:nth-last-child(${childNumber})`).prependTo($autoNavMoreList);
autoNavMore();
} else {
// CODE FIRES WHEN WINDOW SIZE GOES UP
const $autoNavMoreFirst = $autoNavMoreList.children('li:first-child').width();
// CHECK IF ITEM HAS ENOUGH SPACE TO PLACE IN MENU
if(($autoNavWidth + $autoNavMoreFirst) < $menuWidth) {
$autoNavMoreList.children('li:first-child').insertBefore($autoNavMore);
}
}
if($autoNavMoreList.children().length > 0) {
$autoNavMore.show();
childNumber = 2;
} else {
$autoNavMore.hide();
childNumber = 1;
}
}
}
// INIT
autoNavMore();
$(window).resize(autoNavMore);
.main-menu {
max-width: 800px;
}
.main-nav {
display: inline-flex;
padding: 0;
list-style: none;
}
.main-nav li a {
padding: 10px;
text-transform: capitalize;
white-space: nowrap;
font-size: 30px;
font-family: sans-serif;
text-decoration: none;
}
.more-btn {
color: red;
}
.auto-nav-more {
position: relative;
}
.auto-nav-more-list {
position: absolute;
right: 0;
opacity: 0;
visibility: hidden;
transition: 0.2s;
text-align: right;
padding: 0;
list-style: none;
background: grey;
border-radius: 4px;
}
.auto-nav-more:hover .auto-nav-more-list {
opacity: 1;
visibility: visible;
}

The script that Abhitalks made did not work properly for different element sizes. I modified the code a little bit do that it does:
$(function() {
function makeMenuFit() {
//Get data
var menuSize = menu.width();
//Determine how many items that fit
var menuTotalWidth = 0;
var itemThatFit = 0;
for(var i = 0; i < menuItems.length; i++) {
menuTotalWidth += menuItems[i];
if(menuTotalWidth <= menuSize) {
itemThatFit++;
continue;
}
break;
}
menu.children().css({"display": "block", "width": "auto"});
var collectedSet = menu.children(":gt(" + (itemThatFit - 1) + ")");
$("#submenu").empty().append(collectedSet.clone());
collectedSet.css({"display": "none", "width": "0"});
}
var menu = $(".tabletNavigation > ul");
var menuItems = [];
menu.children().each(function() {
menuItems.push($(this).outerWidth());
});
$(window).resize(makeMenuFit);
makeMenuFit();
});