Sticky header that is transparent over main banner? - javascript

I've built a client's site on Squarespace.
I want to create a header that:
1) Has a transparent background when the user first arrives on the page
2) When the user scrolls down, gets a background color and remains affixed to the top of the viewport.
Thanks!

Some info
CSSTricks have a great little example on how to do this (this is the common solution for this).
The basics for this solution is that you listen to the scroll event and check when you get to the right spot (you can calculate that spot programmatically if you want). If you do, you add a class to the header that does the following:
makes the header colored like you wanted it to be
make the header position: fixed; top: <num>; or position: absolute; top: <num> (I've seen both solutions out in the field)
!IMPORTANT! the position:absolute solution is less safe, since position: fixed positions the element relative to the viewport. position:absolute will do the same only if it doesn't have any predecessor with a position:relative [for more info, check this link ]
There's an experimental css feature for position which will add a position: sticky option. In theory, this will do the sticky part by itself [You can see it's experimental by the Experimental Badge next to it on MDN].
The actual solution
https://css-tricks.com/scroll-fix-content/
It also includes a demo with the code on codepen.io. Just notice that you need to scroll the view box (class="wrap") and not the page itself.

You have to combine a few things.
First of all, in your css set for the header position: fixed
You have then to set the transparency. Something like should be enough: opacity: 0.5. You can even use RGBA to specify both color and transparency (I like this one more): background-color: rgba(255, 0, 0, 0.3)
Last, you have to bind an handler to to scroll event with JavaScript. If you can use jQuery, something like this should suffice (I suppose you have an element with id="header"):
$("#header").scroll(myScrollHandler);
function myScrollHandler () {
if (window.pageYOffset > 50)
{
$("#header").fadeTo(200, 0.9);
}
else
{
$("#header").fadeTo(200, 0.3);
}
}
I used sample values, the first one is the duration in ms, the second the target opacity, where 0 is invisible and 1 is full. In the if I compare the offset of the page to the number of pixels after wich the header will start appearing.
So, to recap, in your css you should have something like this:
#header {
position: fixed;
top: 0;
width: 100%;
rgba(255, 0, 0, 0.3);
}
in your html something like this
<script>
$("#header").scroll(myScrollHandler);
function myScrollHandler () {
if (window.pageYOffset > 50)
{
$("#header").fadeTo(200, 0.9);
}
else
{
$("#header").fadeTo(200, 0.5);
}
}
</script>
<div id="header">
Your header content
</div>

Related

Is it possible to make a see-through window using HTML/JS/CSS?

I need to make a see-through window when user click in a given position of the screen, something like this:
It is, I need to highlight an arbitrary area in the screen (with a fixed width and height) in the position where the user clicks.
I have two options:
Use a plugin to take screenshots (like these).
Create 4 grayed boxes.
I don't like none of these options for different reasons:
The use of these plugins exceds my needs and adds an extra page load time and undesired complexity.
Manage these boxes may be complex in a future and browser compatibility may be an issue.
So, my question is, is there any way to do this in a simple manner using HTML (HTML5 and canvas is ok), CSS and Javascript/Jquery? A specific Jquery plugin will be an option due I could forget the maintenance of this code.
I did this once, I am not sure everyone will agree with my implementation but it worked for me at the time:
Create a div in the location you want, set height and width (for window effect);
position the div in the place you wish and then just add outline to it.
body {
background-image: url(http://lorempixel.com/800/800/nature/5/);
background-size: cover;
}
.windowDiv {
position: absolute;
top: 100px;
left: 100px;
height: 300px;
width: 300px;
outline: 4000px solid rgba(0, 0, 0, 0.5);
}
<div class="windowDiv"></div>
EDIT: use background-color rather than opacity.
2nd EDIT: as A.Wolf suggested you should use outline instead of border for easier positioning.

Minimum / Maximum absolute position in CSS

What is the best approach to restricting an absolutely positioned element's position, ideally in pure CSS?
I know that the following isn't possible but I guess what I'm looking for would look something like:
.stickyElement{
bottom-max:auto;
bottom-min:0px;
top-max: auto;
top-min: 100px;
}
That would allow an element to move to a position no less than 100px from the top of it's containing, positioned element.
An example (and my initial) use case for this is a menu that scrolls as part of a page but stops scrolling when it hits the top of a viewport. (Sticky menus?) an example of which can be seen on this page:
http://spektrummedia.com/startups
I fully expect that this is not possible without using some Javascript but I thought I'd put it out there.
position: sticky
There have been discussions in the W3C about this in recent years. One proposal is the addition of a sticky value for the position property.
.content {
position: -webkit-sticky;
position: -moz-sticky;
position: -ms-sticky;
position: -o-sticky;
position: sticky;
top: 10px;
}
This is currently supported in Chrome 23.0.1247.0 and later as an experimental feature. To enable it, enter about:flags for the URL address and press enter. Then search for "experimental WebKit features" and toggle it between enabled and disabled.
On the html5rocks website, there's a working demo.
Strictly speaking, this is an implementation of sticky content, and not a general-purpose way to limit the minimum or maximum position of an element relative to another element. However, sticky content might be the only practical application for the type of the behavior you're describing.
As there is no way to build this for all major browsers without the use of JavasScript I made my own solution with jQuery:
Assign position:relative to your sticky-top-menu. When it reaches the top of the browser window through scrolling the position is changed to positon:fixed.
Also give your sticky-top-menu top:0 to make sure that it sticks to the top of your browser window.
Here you find a working JSFiddle Example.
HTML
<header>I'm the Header</header>
<div class="sticky-top-menu">
<nav>
Page 1
Page 2
</nav>
</div>
<div class="content">
<p>Some content...</p>
</div>
jQuery
$(window).scroll(function () {
var headerTop = $("header").offset().top + $("header").outerHeight();
if ($(window).scrollTop() > headerTop) {
//when the header reaches the top of the window change position to fixed
$(".sticky-top-menu").css("position", "fixed");
} else {
//put position back to relative
$(".sticky-top-menu").css("position", "relative");
}
});
CSS
.sticky-top-menu {
position:relative;
top: 0px;
width: 100%;
}
I know this post is old, and I might be a little late to it, but to anyone still wondering how to do this i would suggest checking out the clamp() method in CSS, you could do something like this:
top: clamp(30px, 10vw, 50px);
Which would set the min top value to 30px, the ideal value to 10vw, and the max value to 50px.
A media query expression that defines the distance between body 0X 0Y and browser-window 0X 0Y would allow elements to be made sticky after page is scrolled
No such expression has otherwise been proposed and is not supported by any browser, to my knowledge, but it would be a useful expression to allow dynamic configuration of sticky elements, such as menu bars that are sticky after page is scrolled past head, without use of JavaScript.
.this element {
position: absolute;
top: 200px;
}
#media (max-scroll: 200px 0) {
.this.element {
position:fixed;
top: 0;
}
}
To my knowledge, there is no way to restrict an element that was positioned using absolute positioning using solely CSS.

CSS and JS - Extend background image beyond div

I'm currently trying to find a workaround to having arrows on Niall Doherty's Coda Slider 2 to highlight the selected tab. Initially I tried doing this with images on the header image, although whilst it looked fine in Safari on my Mac, it wasn't central on other devices (see www.lukekendalldesign.co.uk/pss/productsandservices)
I tried creating this using CSS arrows but that proved rather difficult, so I've found a workaround using a background image, but I've come across yet another problem.
http://cl.ly/HovO (Sorry, I can't upload images - newbie!)
Please refer to the above linked screenshot. The lighter grey triangle that matches the background is part of the header image. The black triangle is positioned using the following CSS code:
.coda-nav ul li a.current {
border-top-right-radius: 10px;
border-top-left-radius: 10px;
color: white;
height: 60px;
z-index: 20000;
background: url(../images/triangle.png) no-repeat 50% 100%;
position: relative;
overflow: visible;
}
What I'm trying to do, is position this black arrow where the grey image arrow is (if that makes sense at all?) How can I do this?
I have tried adding margins and padding, however it extends the grey background and doesn't push the background image black triangle down.
Whilst I have found solutions similar, none seem to apply because the class .current is applied using the following JS:
// If we need a tabbed nav
$('#coda-nav-' + sliderCount + ' a').each(function(z) {
// What happens when a nav link is clicked
$(this).bind("click", function() {
navClicks++;
$(this).addClass('current').parents('ul').find('a').not($(this)).removeClass('current');
offset = - (panelWidth*z);
alterPanelHeight(z);
currentPanel = z + 1;
$('.panel-container', slider).animate({ marginLeft: offset }, settings.slideEaseDuration, settings.slideEaseFunction);
if (!settings.crossLinking) { return false }; // Don't change the URL hash unless cross-linking is specified
});
});
I would very much appreciate any help anyone can offer me on this - as it's a JS issue it's something that's a bit out of my depth! :(
I have tried this in Firefox using fire bug on windows. I think there are 2 problems. The first is that the margin on the ul element should be 167px (the black arrow is not in a nice place in the image (middle is at 232 px did you mean this?).
The the arrow just needs moving down which I did by setting the back ground position to be:
url("../images/triangle.png") no-repeat scroll 50px 60px transparent hope this helps.

Filmstrip Style Image Gallery

I am trying to figure out how to create an image gallery like the one illustrated below so I can place it onto my website. I am wondering if anyone can point me in the right direction for a tutorial? I have found a lot of nice galleries that will display my images, but none of them displays the images like in the filmstrip style I am after.
Requirements of gallery:
When clicking on the arrows, the gallery strip will either shift
left/right by one picture
Hovering over the image will darken the image, and display some
caption about the image
I just answered a question where someone was using carouFredSel. This jQuery plugin looks like it would work pretty well, though I do not think it has the built-in hover effect. To be honest though, that is the easier part.
The trick is to make the width slightly larger than the images to show, which leads to the partial images on each side.
Here is a jsfiddle to illustrate.
UPDATE:
The OP asked if the page nav links could be repositioned. I modified the jsfiddle to work this way. The additions were as follows:
.list_carousel {
position: relative;
}
#prev2 {
position: absolute;
top: 35px;
left: 0;
}
#next2 {
position: absolute;
top: 35px;
right: 0;
}
If you have a relatively positioned container element, you can absolutely position child elements. I added relative positioning to the list_carousel container, then I could absolutely position the nav arrows within the container. Change the top value to position vertically, and left/right to position horizontally.
I also removed the pager all together, as it was not a requirement based on the original example. If you change the page arrows to images it is pretty much what you want.
MORE UPDATES
I decided to take it one step further and make the hover effect work more like the example. See the new jsfiddle. The changes are:
Added span wrappers around all text within list items
Added $(".list_carousel li span").hide(); to hide all the spans
Modified hover event to toggle spans
I also added some CSS to position the span text:
.list_carousel li {
position: relative;
}
.list_carousel li span {
position: absolute;
bottom: 0;
display: block;
text-align: center;
width: 100%;
}
FINAL UPDATE (I PROMISE!)
I decided to go all in and add the transparency layer too: jsfiddle
Hover modifications:
$(this).prepend($("<div class='hover-transparency'></div>")); and $(this).find("div:first").remove(); to add/remove transparency layer on hover in/out.
CSS modifications:
.hover-transparency {
position: absolute;
top: 0;
right: 0;
bottom: 0;
left: 0;
background-color: rgba(0, 0, 0, 0.60);
}
These style the transparency layer. Change to suit your taste.
Something like jCarousel should do the trick. Once you have the carousel functionality in place, you can add in the hover affect via CSS and a span that contains the caption.
I was just looking at ContentFlow Plugin which is JavaScript based.
They include a separate library of additional plugin you can use that takes care of your Slideshow requirements, in particularity this one HERE. When you use the mousewheel over the 3 images, it scrolls by 1. That said, you can mod the plugin to do the same when the arrow buttons are clicked.
Sample plugin markup looks like:
{
shownItems: 3, //number of visible items
showCaption: true // show item caption
width: 100, // relative item width
height: 100, // relative item height
space: 0.4 // relative item spacing
}
To address that the captions should be visible only on mouse hover, I would set showCaption to always be true along with using a jQuery .hover(); Event Listener that will use .show(); and .hide(); on the caption Class Name .caption when required. Also, using jQuery to set the opacity can be done within the .hover(); event too.
The latest version of ContentFlow v1.0.2 supports multiple instances on the same webpage if that's ever required.

Dynamic Background Scrolling

Here's a link to what I'll be referring to.
I'm having some trouble getting the background image to work the way I'd like it to.
I want the background to auto resize based on the width of the window, which it is already doing correctly. If you make your window smaller you'll see the background shrink with it.
Here's the issue. If you make your window wide (short) then the background will resize and go too high so you can't see the top of the background anymore (since the background is bottom positioned).
I want the background to be top position when you are at the top of the page, and as you scroll down it will slowly move to be bottom positioned. Sort of like the effect of an Android phone's background when you move left and right. Of course, keep in mind that I still want the background to auto-resize when you make the window smaller.
html {
background-color: #70d4e3;
height: 100%;
}
body {
height: 100%;
}
.background {
margin-top: 45px;
width: 100%;
position: fixed;
bottom: 0;
left: 0;
z-index: -9999;
}
.banner {
margin: 0px auto;
width: 991px;
margin-bottom: -9px;
}
.content {
background: url("http://i.imgur.com/daRJl.png") no-repeat scroll center center transparent;
height: 889px;
margin: 0 auto;
width: 869px;
}
.innerContent {
padding: 30px;
}
<img src="http://i.imgur.com/6d5Cm.jpg" alt="" class="background" />
<div class="banner">
<img src="http://i.imgur.com/JptsZ.jpg" alt="" />
</div>
<div class="content">
<div class="innerContent">
testing
</div>
</div>
Maybe some javascript or jquery would be needed to achieve this.
Well, this was fun, thanks!
I hope you don't mind me taking the liberty to use percentages to make my life a little bit easier and possibly the script slightly more robust since I can reliably use floats with percentages.
What I did is make the layout, html and css comply with the rules you need for the bg to be animated properly, they stayed largely the same from what you had.
Then it was just a question of figuring out the calculations needed with the right properties to figure out the percentage you were from the top, the *20 is actually the amount of space 'left' to fill by the background image in percentages (as the background height is 80%).
They I moved the calculations to a function so I could call that on scroll and on window resize, making sure it's initiated on any event that modifies the window somehow...
Didn't do extensive testing but it worked in Chrome and I'm tired :p
I believe this is what you are looking for:
http://jsfiddle.net/sg3s/RSqrw/15/ See edit 2
If you wanted this the other way arround just make the page background start at the top and modify that:
http://jsfiddle.net/sg3s/RSqrw/14/ See edit 2
Edit:
As a bonus, and since I had never actually written jquery script as a 'plugin', I decided to convert this into one. What I came up with should be easy to implement and use!
http://jsfiddle.net/sg3s/RSqrw/52/ See Edit 3
Functionality successfully tested in Chrome, Firefox 3.6, IE9 + compatibility mode
Edit 2:
Reading the question again checking if I did it right I noticed I didn't quite do what you want, so I updated the link in the first edit which gives you a plugin in which you can have several options for the scrolling background. It retains my 'old' interpetation while also doing what you want... Read comments in code for some extra descriptions.
Edit 3:
As I went to work today I was bothered with the fact that my plugin 'try' was a little bloated. And as you mentioned in the comment it didn't quite fit the requirements.
So I rewrote it to only do what you want and not much more, tested in Chrome Firefox, IE9 +compat etc etc.. This script is a lot cleaner.
http://jsfiddle.net/sg3s/vZxHW/
You can chose to make the background stick to the top or bottom if the height fits in the window. Nothing else, but that is already more than enough to do some pretty cool stuff :p
An exact solution: Fiddle: http://jsfiddle.net/srGHE/2/show/
View source
Thanks for the challenge. See below for the solution, which is complying with all requirements, including recommended yet optional (with steps on how to remove these) features. I only show the changed parts of your page, with an explanation after each section (CSS, HTML and JavaScript):
CSS (changes):
html,body{
margin: 0;
height: 100%;
padding: 0;
}
body{
background-color: #70d4e3;
}
#background { /*Previously: .background*/
/*Removed: margin-top: 45px;
No other changes*/
}
#banner /*Previously: .banner; no other changes */
#content /*Previously: .content; no other changes */
#innerContent /*Previously: .innerContent; no other changes */
Explanation of CSS revisions:
margin-top:45px at the background is unnecessary, since you're absolutely positioning the element.
All of the elements which are unlikely to appear more than once should be selected via the id (#) selector. This selector is more specific than the class selector.
HTML (changes):
All of the class attributes have been replaced by id. No other changes have been made. Don't forget to include the JQuery framework, because I've implemented your wishes using JQuery.
JavaScript (new):
Note: I have added a feature which you didn't request, but seems logical. The code will automatically reserve sufficient margin at the left side of the window in order to always display the background. Remove anything between the marked comments if you don't want this feature.
$(document).ready(function(){
//"Static" variables
var background = $("#background");
var marginTop = parseFloat(background.css("margin-top")) || 0;
var bannerWidth = $("#banner").width(); /*Part of auto left-margin */
var extraContWidth = (bannerWidth - $("#content").width())/2; /*Same as above*/
function fixBG(){
var bodyWidth = $("body").width();
var body_bg_width_ratio = bodyWidth/1920;
var bgHeight = body_bg_width_ratio * 926; //Calcs the visible height of BG
var height = $(document).height();
var docHeight = $(window).height();
var difHeight = bgHeight - docHeight;
var scrollDif = $(document).scrollTop() / (height - docHeight) || 0;
/*Start of automatic left-margin*/
var arrowWidth = body_bg_width_ratio * 115; //Arrow width
if(bodyWidth - bannerWidth > arrowWidth*2){
$("body > div").css("margin-left", "auto");
} else {
$("body > #banner").css("margin-left", arrowWidth+"px");
$("body > #content").css("margin-left", (arrowWidth+extraContWidth)+"px");
}
/*End of automatic left-margin*/
if(difHeight > 0){
background.css({top:(-scrollDif*difHeight-marginTop)+"px", bottom:""});
} else {
background.css({top:"", bottom:"0"});
}
}
$(window).resize(fixBG);
$(window).scroll(fixBG);
fixBG();
});
Explanation of the JavaScript code
The size of the background is determined by calculating the ratio of the background and document width. The width property is used, because it's the most reliable method for the calculation.
Then, the height of the viewport, document body and background is calculated. If applicable, the scrolling offset is also calculated, to prepare the movement of the background, if necessary.
Optionally, the code determines whether it's necessary to adjust the left margin (to keep the background visible at a narrow window).
Finally, if the background arrow has a greater height than the document's body, the background is moved accordingly, taking the scrolling position into account. The arrow starts at the top of the document, and will move up as the user scrolls (so that the bottom side of the arrow will be the bottom of the page when the user has fully scrolled down). If it's unnecessary to move the background, because it already suits well, the background will be positioned at the bottom of the page.
When the page has finished loading, this functionality is added to the Resize and scroll events, so that the background is always at the right location.
If you've got any other questions, feel free to ask them.
well, I'm not sure if I understand you and why do you want to do that, but you can try adding 2 backgrounds (see http://www.css3.info/preview/multiple-backgrounds/ ), one with the top bg and another with the bottom bg but I think that if the page is not too long it will cause issues, so the other answer with pure CSS is as follows: first add 3 horizontal divs with 100% width. Top div will have your top bg and its height, middle div will be transparent and auto height and bottom div will have your bottom bg and its height. All divs will have a 0 z-index. Then create a higher z-index div to act as a container and you'll be set. If I understand your question right, that's the close I can think of to achieve that. This being said, I'm pretty sure you can do this with JQuery with way better results
Using jQuery I was able to give you what I think you're asking for:
$(window).scroll(function() {
var h = Math.max($(document).height(), $(window).height());
var bottom = h - $(".background").height() - $(window).height();
$(".background").css("top", (($(window).scrollTop() / h) * bottom) + "px");
});
EDIT: Forgot to account for the way scrollTop reports position.
Or maybe:
.background {
margin-top: 45px;
max-width: 100%;
position: fixed;
bottom: 0;
left: 0;
z-index: -9999;
max-height: 100%;
}
I reccomend using jQuery Background Parallax
http://www.stevefenton.co.uk/Content/Jquery-Background-Parallax/
The function is as simple as
$("body").backgroundparallax();
Ask if you don't get it to work.
#abney; as i understand your question may that's you want http://jsfiddle.net/sandeep/RSqrw/60/
you need only css for this:
#background {
position: fixed;
width: 100%;
height:100%;
top: 0;
left:0;
z-index: -1;
}
The solution to your issue is a nice little lightweight plugin by Scott Robin. You can get more info, download it, and make your life easier for all of your projects by visiting his project page here.

Categories

Resources