Position sticky: overlay - javascript

It is possible to have 2 sticky elements on top of each other? Or use one of them as a background?
TLDR; I was able to make this work with a library (StickyKit) that does what I'm looking for, but performs badly with new async scrolling.
Example
JSFiddle with StickyKit - https://jsfiddle.net/cibulka/4nd3b0tt/ - (this does what I'm describing, but performs poorly, see below)
How I did it: I wrapped sticky elements in the 200% wrapper, and floated them to left. Then I moved 1 of them (margin-left: -100%) on top of the other. This way they are on top of each other, but still keep their height.
Why this does not work with position:sticky
One of many quirks with position:sticky is that it does not work if any of its parents is overflow:hidden. See this answer for more info: Why does `overflow:hidden` prevent `position:sticky` from working?
What I need to do here is to make the 2 elements overlay somehow without their container be overflow:hidden. Or should I do something else entirely?
What I'm using now
For the time being, I've ditched the "200% container" and set my image container (.sticky.bg, see the fiddle) to height:0. This makes images "stuck", but they do not become "relative" again once user scrolls to the bottom.
This is obviously not ideal.
Background
I was a happy user of StickyKit for a long time. Unfortunately, it does not work very well with asynchronous scrolling, which is employed by more and more browsers to improve performance. With the new Firefox Quantum (57), for example, StickyKit is pretty much unusable.
I've created an issue in StickyKit Github, but package seems to be abandonned by the author: https://github.com/leafo/sticky-kit/issues/252
Because of that, I am forced to deprecate StickyKit and move to native position:sticky (polyfilled with StickyFill). Unfortunately there is a couple of things position:sticky can't do and this is one of them.
There is also another issue I'm having with position:sticky: Position sticky: scrollable, when longer than viewport
What I'm looking for
A recommendation, basically, how to approach this issue. I'm up for using different JS/jQuery library, writing my own code or use some quirky CSS hack to hack position:sticky functionality.
Thanks in advance!

Related

Sticky Sidebar Jitters on Scroll

I implemented a sticky sisebar library that aims to be easy to use as you are free in setting up the sidebar and its CSS. The library only gives you an additional value as custom property (--push-down) you can use in CSS to push the sidebar to its current position.
The problem I'm facing is that the script causes massive jitters in the sidebar position on some devices. These do only occur on the first scroll - if you've scrolled through the site once, it's working fine.
I would like to know why that could be the case (and if it's possible to be fixed. If not I still want to find out what's happening here.)
Using throttle functions does not make a difference here, as described here: https://stackoverflow.com/a/44779316/6336728. I'm already using the suggested method of doing layout read on scroll and layout write with requestAnimationFrame.
I put the code of my GitHub repo in this CodePen to try it out quickly; only the JS part is relevant.

Page Pilling or FullPage - How to make this scroll effect

I know that it is not a very precise question, but I do not know where to start, I have an example which is the objective design, however I cannot find any solution and / or documentation to help me make this type of layout.
More specifically this is the scroll effect that I want to do, http://modern8.com/d5-process/
It should be noted that I have already tried with FullPageJS and I have not been able to recreate it, if you can see the effect consists of applying fixed and relative position according to the scroll but as I indicate, I do not know where to start.
I really appreciate the help you can give me.
The effect is the same as in pagePiling.js but pagePiling.js uses snap scroll so you'll snap to each section. There's no scrollbar.
The closer you can get with fullPage.js is by using the paid Parallax extension with autoScrolling: false (to avoid snap) and placing the whole content of the section inside the fp-bg element.
There's an article about it here.
https://alvarotrigo.com/blog/how-create-tumblr-website-effect/

Fixed position in only one direction in future releases of CSS?

I know CSS is not supporting position: fixed for only x or y but only for both a the same time.
The common approach to solve this seem to be to use fixed positioning in combination with jquery to re-position the component with respect to the scroll amount in the non-fixed axis. The downside with this is that the component will lag a lot when scrolling in this direction.
My question is if this is a problem that is being looked at for future specs of CSS? Anyone know?
I think we need a fixed-x and and fixed-y positioning value.
This is especially becoming a problem now with touch devices where scrolling in both dimensions are more common.
Here's a fiddle:
http://jsfiddle.net/UfZPa/1/
which shows what I'm after but not the actual problem because this very small example is very fast as it looks now.
Update
From the CSS ED:
Intersection between the stickily positioned element and the bottom of
the sticky-constraint rectangle limits movement in any direction, so
the offset never pushes the stickily positioned element outside of its
containing block. However, when the element is free to move within its
containing block as the page is scrolled, it appears to be pinned to
the relevant flow root edges, similarly to a fixed position element.
I think this is describing what I want but I'm not sure...
Update 2
To clarify my app is basically a grid with scroll-overflow in both x and y (like Excel). What I want is some labels to stick at the edges in one directionwhen being scrolled out of view but at the same time stay in the normal flow in the opposite direction. I want this for both fixed-x/flow-y and fixed-y/flow-x. And the problem again: With lots of labels this makes scrolling very laggy using the jquery-solution. I think we are missing an option to make components fix in only one dimension and still flow in the other. Maybee I'm the only one wanting this =)
A quick skim through some CSSWG notes such as this one leads me to believe that position: sticky might be a potential solution to this problem, provided you only specify the offsets on the axis you want the element to be fixed.
There is a point of concern though: unlike a fixed element which is considered absolutely positioned, a sticky element starts out relative to its containing block. Since relatively-positioned elements are not taken out of the normal flow, you will have to account for the layout of other elements in the same flow as your element, among other things, and (thus?) forcing the element to act like it's fixed regardless of scroll position may be a little more difficult.
Of course, there is too little information and implementation available to verify any of this — I'm just making an informed guess, and the document I link to is an ED not meant for general reference — but you can always ask the www-style mailing list and see what the good folks there have to say. I haven't experimented enough with position: sticky to be able to comment further myself.

CSS Skill Bar Animation on Scroll

I'm looking to do something like this. I'm using code from this answer here but the answer is never made entirely clear. They are suggested to use this jquery plugin here but I haven't been able to get it to work. I would go with the first example's code, only, I'm using Foundation 4 and the progress bars are something that come with it and are simpler to create. Also, the animation code provided in the second example is a lot cleaner-- overall, the first example is kinda messy, code heavy, and redundant.
My code is live here. I'm working with the skill bars in the about section. Before the user gets to this point, the animation should be paused. Once the user scrolls to this part of the page, the animation should play.
EDIT: Also, if you have any suggestions to stop the bars from "breaking" out of their containers when you scale the page (this site is meant to be responsive), I would appreciate that as well.
EDIT2: I've noticed as I've been playing with this that overflow: hidden; on .progress fixes my "breaking" issue.. however, when you resize the window, the sizes stay at what they initialized at. I know realistically users visiting my site likely won't be resizing the window a whole lot, but for employers looking at it, it'll kinda be lame if it doesn't work properly. I'm having this same issue with the grumpy-cat button overlays where it initializes at the first size and doesn't resize the overlay after that. Suggestions to this would be really, really appreciated!
If you know where your skill bar is and you know where your screen is at, you only need javascript. (no plugins or weird stuff)
To get the vertical position of your screen it's simple:
window.pageYOffset
To get the vertical position of your div, you just need
div.offsetTop
In your case, I would give an id to the div that wraps all the skill bars and set a loop (window.requestAnimationFrame https://developer.mozilla.org/en-US/docs/Web/API/window.requestAnimationFrame ) to check if you're within reach of the div (say, if the difference between the window offset and the div is less than some amount).
If the answer is yes, trigger the animation.
The best way to do the animation is by a css transition. (if you need a good intro to css animations here's a video that i found helpful: http://www.youtube.com/watch?v=VoncDvOfUkk )
You can set css animations from javascript.
The idea is that you would set all your "meter" widths to 0. Then in javascript do something like:
div.style.transition = "width 1s";
div.style.width = someValue;
My recommendation for the value to include in the div is some constant fraction of the "progress" div, as in with % as opposed to em or px. This technique should work. (in case you still have issues, you have a window.requestAnimationFrame loop going on so you can recalculate the values at each timestep... although... beware performance).
The reason you were recommended jQuery is because when you're going to have to update all the divs in order to animate them, just writing $(this).find('.meter') and then addClass('.expand') is so much easier.
Hope this helps

Appending a Vertical Scroll to a Horizontal Scroll Bar

I've been trying to do something like this for quite a bit, and have tried a variety of methods from fake scroll bars and DOM-tricking code. Nothing seems to quite be as clean / functioning as I need it to be.
What I'm trying to do is have a horizontally scrolling div (with scrollbar), with a vertically scrolling div nested within it. Ideally the single horizontal scrollbar would scroll, and after a certain point--vertically scroll the "go-up" div next to it.
Here's an example diagram for those who need to visualize:
I think I have a solution that could work:
Basically I'm thinking that the horizontal "scene" could have overflow that equals the height of the "go-up" div. And after the horizontal width of the "scene" passes...you can, onScroll, shift the "go-up" container right using (ScrollLeft) and up using (ScrollTop).
Basically giving you the illusion of controlling it's vertical scroll with a horizontal scrollbar.
Check out the code here: http://jsfiddle.net/jPzqj/1/
I know how to pass a function at the end of the "scene"...currently I'm using:
$('#main').scroll(function(e)
{
if($(this).scrollLeft()>1430)
{
}
});
My only issue is I'm not quite sure how to approach the math that would allow me to shift the go-up container. How do I pass in the "scene" divs scroll value into the ScrollLeft and ScrollTop values of "go-up"...
Could anyone give me any advice on this at all?
Thanks.
You are totally off the right path, no vertical scrollbars are involved.
That is a good site (not the one that you make in 30 minute obviously), and the javascript is obfuscated, but if you are interested, you could watch the source with Firebug to understand what's going on.
It works by mixing a javascript library, some cool CSS3 Transform3D effects, and a nicely studied HTML to give you the effect of the screen scrolling up (actually, only the images are moving - and not scrolling - while the screen is always in the same Y position).
The same effect is used to create the percetion of depth, by moving the houses in background slower than the ones in front.
This effect is called PARALLAX SCROLLING .
A good javascript library you could start looking at for Parallax effects is Stellar.js
You can take a look at some great sites made with Stellar.js, especially Nike and Saucony.
Hope this answer saved you some time,
good luck on your studies ;)
EDIT
this is what you want: Jquery Parallax Scrolling effect - Multi directional
open the fiddle from the bounty-awarded answer and keep the right arrow key down.

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