Develop Reference

How would I make my Bootstrap navbar "collapse"?

I am trying to replicate the scrolling effect from here: http://www.altisliferpg.com/
I have a feeling that they are using a heavily modified version of Bootstrap Navbar, which I have taken from here: http://www.enjin.com/forums/page/1/m/10826/viewthread/8514993-boot-strap-30-navbar-full-module and have changed it to fit into my specific case.
How would I make it so when you scroll down the page, the bar on the top gets "smaller" and scrolls along with the page as you scroll? Thanks

You can use css transitions for the height, font size and whatever else you want changed. Then simply set a scroll listener, which adds a class to the header so the size changes. Quick (and very ugly) example. jsFiddle
$(window).scroll(function () {
if ($(this).scrollTop()) {
$('#header').addClass('small');
}
else {
$('#header').removeClass('small');
}
});

Maybe you should detect the scroll event of the window, after that, set the position of the navbar to fixed and then, perform the animation. Here's an example of the javascript part and a link see it in action:
$(function(){
var performingDownAnimation = false,
performingUpAnimation = false;
var performScroll = function(){
if($("body").scrollTop() > 0) {
if(performingUpAnimation) {
$('#logo').stop();
performingUpAnimation = false;
}
if(!performingDownAnimation){
$('#navbar').addClass('navbar-fixed');
$('#logo').animate({ 'font-size': "12px" }, 1000, function(){
performingDownAnimation = false;
});
performingDownAnimation = true;
}
}else if($("body").scrollTop() == 0){
if(performingDownAnimation) {
$('#logo').stop();
performingDownAnimation = false;
}
if(!performingUpAnimation){
$('#navbar').removeClass('navbar-fixed');
$('#logo').animate({ 'font-size': "48px" }, 1000, function(){
performingUpAnimation = false;
});
performingUpAnimation = true;
}
}
}
$(document).on('scroll', performScroll);
});
On scroll event and position fixed
I edited my response for adding support for the "up" direction too. About using bootstrap for the animation, I have no idea how to do it, and I think it can't be done, because bootstrap is based mainly on applying CSS classes to different elements. CSS classes are discrete, but you are asking for animating something numerical, as the font-size property is. As much, you could create an animation that looks "staggered".

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);

Do not execute jQuery script if CSS is of particular value

On my website, I have a sidebar DIV on the left and a text DIV on the right. I wanted to make the sidebar follow the reader as he or she scrolls down so I DuckDuckGo'ed a bit and found this then modified it slightly to my needs:
<script type='text/javascript'>//<![CDATA[
$(window).load(function(){
$(function(){
var $sidebar = $('#sidebar'),
sidebarOffset = $sidebar.offset(),
$window = $(window),
gap = $('#header').css('marginBottom').replace(/[^-\d\.]/g, ''),
distance = ($window.scrollTop()) - (sidebarOffset.top - gap),
footerHeight = $('#footer').outerHeight();
$window.scroll(function(){
distance = ($window.scrollTop()) - (sidebarOffset.top - gap);
if ( distance > 0 ) {
$sidebar.css({'top': gap + 'px', 'position' : 'fixed'});
} else {
$sidebar.css({'top': '0', 'position': 'relative'});
}
})
});
});//]]>
</script>
And it works just like I want it to. However, my website uses Skeleton framework to handle responsive design. I've designed it so that when it goes down to mobile devices (horizontal then vertical), sidebar moves from being to the left of the text to being above it so that text DIV can take 100% width. As you can probably imagine, this script causes the sidebar to cover parts of text as you scroll down.
I am completely new to jQuery and I am doing my best through trial-and-error but I've given up. What I need help with is to make this script not execute if a certain DIV has a certain CSS value (i.e. #header-logo is display: none).
Ideally, the script should check for this when user resizes the browser, not on website load, in case user resizes the browser window from normal size to mobile size.
I imagine it should be enough to wrap it in some IF-ELSE statement but I am starting to pull the hair out of my head by now. And since I don't have too much hair anyway, I need help!
Thanks a lot in advance!

This function will execute on window resize and will check if #header-logo is visible.
$(window).resize(function() {
if ($('#header-logo').is(':visible')) {
// Your code
}
});
I think you need to check this on load to, because you don't know if the user will start with mobile view or not. You could do something like this:
$(window).resize(function() {
if ($('#header-logo').is(':visible')) {
// Your code
}
}).resize();
This will get executed on load and on resize.
EDIT: You will probably need to turn off the scroll function if #header-logo is not visible. So, instead of create the function inside the scroll event, you need to create it outside:
$(window).resize(function() {
if ($('#header-logo').is(':visible')) {
var $sidebar = $('#sidebar'),
sidebarOffset = $sidebar.offset(),
$window = $(window),
gap = $('#header').css('marginBottom').replace(/[^-\d\.]/g, ''),
distance = ($window.scrollTop()) - (sidebarOffset.top - gap),
footerHeight = $('#footer').outerHeight();
function myScroll() {
distance = ($window.scrollTop()) - (sidebarOffset.top - gap);
if ( distance > 0 ) {
$sidebar.css({'top': gap + 'px', 'position' : 'fixed'});
} else {
$sidebar.css({'top': '0', 'position': 'relative'});
}
}
$window.on('scroll', myScroll);
} else {
$(window).off('scroll', myScroll);
}
});
Didn't test it, but you get the idea.

$("#headerLogo").css("display") will get you the value.
http://api.jquery.com/css/
I also see you only want this to happen on resize, so wrap it in jquery's resize() function:
https://api.jquery.com/resize/

Slide boxes with margin-left check if overslided

I made a simple content/box slider which uses the following javascript:
$('#left').click(function () {
$('#videos').animate({
marginLeft: '-=800px'
}, 500);
});
$('#right').click(function () {
$('#videos').animate({
marginLeft: '+=800px'
}, 500);
});
Here is the demo: http://jsfiddle.net/tjset/2/
What I want to do and I can't figure out how to show and hide arrows(left and right box) as the all the boxes slided.
So I clicked 4 time to the LEFT and slided all the boxes! then hide "left" so that you can't give more -800px
What can I do?

What you can do is check after the animation completes to see if the margin-left property is smaller or larger than the bounds of the video <div>. If it is, depending on which navigation button was clicked, hide the appropriate navigation link.
Check out the code below:
$('#left').click(function () {
// reset the #right navigation button to show
$('#right').show();
$('#videos').animate({
marginLeft: '-=800px'
}, 500, 'linear', function(){
// grab the margin-left property
var mLeft = parseInt($('#videos').css('marginLeft'));
// store the width of the #video div
// invert the number since the margin left is a negative value
var videoWidth = $('#videos').width() * -1;
// if the left margin that is set is less than the videoWidth var,
// hide the #left navigation. Otherwise, keep it shown
if(mLeft < videoWidth){
$('#left').hide();
} else {
$('#left').show();
}
});
});
// do similar things if the right button is clicked
$('#right').click(function () {
$('#left').show();
$('#videos').animate({
marginLeft: '+=800px'
}, 500, 'linear', function(){
var mRight = parseInt($('#videos').css('marginLeft'));
if(mRight > 100){
$('#right').hide();
} else {
$('#right').show();
}
});
});
Check out the jsfiddle:
http://jsfiddle.net/dnVYW/1/

There are many jQuery plugins for this. First determine how many results there are, then determine how many you want visible, then use another variable to keep track with how many are hidden to the left and how many are hidden to the right. So...
var total = TOTAL_RESULTS;
var leftScrolled = 0;
var rightScrolled = total - 3; // minus 3, since you want 3 displayed at a time.
instead of using marginLeft I would wrap all of these inside of a wrapper and set the positions to absolute. Then animate using "left" property or "right". There's a lot of code required to do this, well not MUCH, but since there are many plugins, I think you'd be better off searching jquery.com for a plugin and look for examples on how to do this. marginLeft is just not the way to go, since it can cause many viewing problems depending on what version of browser you are using.

How do you make a floating sidebar like envato?

I really like the floating panel on the left side of the following site:
http://envato.com/
I have no idea what its called, but I like how when you click on the search button, it expands to a search page, you click on another icon, and it expands with what appears like its own page.
How do I accomplish this? Is there some tutorial out there using html5, JavaScript or jQuery?
NOTE: All the answers so far only cover the floating bar, but not the clicking on a link on that floating bar to show a window expanded to the right.

<div id="float"></div>
#float{
position:fixed;
top:50px;
left:0;
}
Check working example at http://jsfiddle.net/TVwAv/

done using css,
HTML
<div id="floating_sidebar">
whatever you want to put here
</div>
CSS
#floating_sidebar {
position:fixed;
left: 0;
top: 100px; /* change to adjust height from the top of the page */
}

I am using this for a "floating (sticky) menu". What I have added is:
1. to avoid my 'footer' always being "scrolled" down in case the sidemenu is a little high, I only do the scrolling if necessary, i.e -
when the content is higher than the sidebar.
2. I found the animate effect a little "jumpy" to my taste, so I just changed the css through jquery. of-course you put a 0 in the animate time, but the animation still occurs, so it's cleaner and faster to use the css.
3. 100 is the height of my header. you can assume it to be the "threshold" of when to do the scrolling.
$(window).scroll(function(){
if ($('#sidebar').height() < $('#content').height())
{
if ($(this).scrollTop() > 90)
$('#sidebar').css({"margin-top": ($(this).scrollTop()) - 100 });
//$('#sidebar').animate({"marginTop": ($(this).scrollTop()) - 100 }, 0);
else
$('#sidebar').css({"margin-top": ($(this).scrollTop()) });
//$('#sidebar').animate({"marginTop": ($(this).scrollTop()) }, 0);
}
});`

you can use this ..
your html div is here
<div id="scrolling_div">Your text here</div>
And you javascript function is here
$(window).scroll(function(){
$('#scrolling_div').stop().animate({"marginTop": ($(this).scrollTop()) +10+ "px"}, "slow"});
});
You can also use the css for this
#scrolling_div {
position:absolute;
left: 0;
top: 100px;
}
I have not tested it but hopefully its worked.

I know this looks quite a big piece of code, however this function just works by specifying three simple options; your floater "top", your "target" (floater) and "reference" element to set the boundaries, it also takes care of the top and bottom position automatically, no css involved.
function scrollFloater(marginTop, reference, target, fixWhidth = false){
var processScroll = function(){
var from = reference.offset().top - marginTop;
var to = reference.offset().top + reference.outerHeight() + marginTop - target.outerHeight();
var scrollTop = $(this).scrollTop();
var bottom = to - reference.offset().top + marginTop;
if( fixWhidth )
target.css('width', target.width());
if( scrollTop > from && scrollTop < to )
target.css('position', 'fixed').css('top',marginTop);
else if( scrollTop >= to )
target.css('position', 'absolute').css('top', bottom);
else
target.css('position', '').css('top',marginTop);
}
$(window).scroll(function(){ processScroll(); });
processScroll();
}
And this is how you would use it:
$(function() {
scrollFloater(41, $('.box.auth.register'), $('.plans-floater'), true);
});
I hope this helps someone.