-webkit-overflow-scrolling breaks absolute positioning - javascript

I am building a page that needs to have some elements which stick to the top of the page when they would otherwise be scrolled off the screen. I managed to do this using position:absolute. Everything was working perfectly, but it needed momentum scrolling. I added -webkit-overflow-scrolling: touch to the css of the scrollable area. This broke everything. My sticky elements with position:absolute are now just scrolling with the rest of the content.
My question is this:
Why does -webkit-overflow-scrolling: touch affect absolute positioning, and is there a way around this?
UPDATE: I added an alert whenever a child element becomes "fixed" or "unfixed". The alerts continue to fire, so the styling is still being applied, it just isn't working. This means that it's not a problem with keeping track of scroll position but rather a problem with the styling.
UPDATE: I tried using position: fixed instead of position: absolute and -webkit-overflow-scrolling broke that too
UPDATE: After a lot of digging, I found references to this problem here and here. However, the only proposed solution in both cases is to restructure the DOM so that the sticky elements are not in the scrollable area. This is a difficult thing to do in my case, and I would prefer not to have to. Have things progressed since ios5 or is that still the only option?

On the last question - yes the issue is present in ios5. Extracting the absolute positioning element outside of the scrollable area worked fine for me.

Related

Will CSS position:fixed block event handling?

Show you code first:
https://codesandbox.io/s/vigorous-fog-te1bw?file=/index.html
Please focus on two points:
full-size-bg is full screen background, it use a fixed div to adjust the alpha instead of set background to parent node because I do not want to modify the real image alpha.
scroll-area is above the full-size-bg and it`s(should be) a scrollable area which height is longer than visible area
Then what I want to know is the fixed background will block the event handling if I do not add position: absolute in scroll-area, the scroll area can not scroll with mouse wheel(but it can scroll if use up and down arrow key, Why?). Of course fiexed will leave document flow for layouting, but also for event handling?
Second, Chrome do not need add the z-index line, but Firefox need, Why??
Third, What I need now is a standard way to set a full screen background with alpha programmatically?
Thanks a lot.
Basically, in your example code, the fixed position does not prevent scrolling. The problem is, when you don't set position: absolute for scroll-area div, the full-size-bg div is HIGHER z-index. You can see that by inspecting in developer tool by right clicking, it will show the top "front" element.
You can find an answer here also: z-index not working with fixed positioning.
For question about firefox vs chrome z-index, you can see more here: z-index behaviour is different in chrome to firefox
For third question, I don't understand correctly :(

html margin issue - "Shaking" Website

Im working on a Website and everything is ok, except my webside is "shaking". (I'm using chrome)
The margin of my main Container is changing on some sides and i have no idea why. They have the same html code, it must have something to do with the content in the main div-container
My Website: www.anitalernt.de
http://www.anitalernt.de/about-us.html is a bit more to the left and http://www.anitalernt.de/index.html after getting a task (just click some buttons) also.
Has someone a idea?
Always display the scrollbar
html {
overflow-y: scroll;
}
See:
Always show browser scrollbar to prevent page jumping
How to always show the vertical scrollbar in a browser?
You could add
html{ overflow-y: scroll;}
to your css.
Places a permanent (but sometimes empty) scroll bar on the window
The issue is most likely caused by the scrollbar appearing, which reduces the viewable area of the browser window and may adjust the contents accordingly.
There are a couple possible workarounds:
You could extend the length of the adjusted web-page so that the content (post-adjustment) also runs "below the fold"
Alternatively, you could encase everything in an absolute positioned DIV which won't "shake" when the viewable area contracts on the scrollbar's appearance.
Or -- depending on your specific content -- you could disable the scrollbar. Although this last workaround is only advisable in very specific cases.
body{
margin: 0;
}
seems to resolve this without having to add a dummy scrollbar :)
I had the same problem because of jQuery scroll where I was checking the scroll value and using that. I fixed my navigation bar by using addClass and removeClass, adding class was not working because I did not use !important in CSS class.

Mobile Safari prevent body scroll when menu open

I have been fighting with this thing for several weeks now. I just can't figure it out.
I'm trying to prevent horizontal scrolling of the body when the menu is open. Here is a complete jsbin:
http://jsbin.com/vopeq/38/edit
Seems like any solution only undoes other things that are working the way I would like them to. So I added the requirements to the jsbin to keep track of which are satisfied with each version.
UPDATE
Maybe it's too good to be true, but I think I have all requirements satisfied, but I still need to check on android devices:
http://jsbin.com/vopeq/61
The thing I learned, that was tripping me up for so long and I didn't realize it, is that overflow: hidden on the <body> element, in Mobile Safari, doesn't do squat! I had to move my styles to prevent scrolling down one level of elements.
And Ed4 pointed me in the right direction. I needed to set overflow: hidden on the parent of the element I'm moving with left: 85% instead of the element itself (I was trying to do it all on the <body>).
So I have a body > .container, on which I do the overflow: hidden and body > .container > .content, which I push over using position: relative and left: 85%.
Your question is more of a design spec than a question, so rather than try to design the whole layout for you, I'll point out why your jsbin doesn't work.
Don't try to set left on body. If body is protruding offscreen, you're not going to be able to reliably stop scrolling.
Instead, keep body stationary with 100% width and height, so it can serve as your visible window boundary. When you want to lock the scrolling, you can set overflow: hidden on body. Handle the slide-over and scrolling menu with separate divs inside body.

Constraints and draggable item not appearing on top - Version II

OK, so here's the situation:
I'm experimenting with a fixed-width (resizeable) left sidebar
The sidebar contains draggable elements
If one of the elements is dragged to the right, then the draggable element (the helper actually) seems to be disappearing behind the main content.
Why is that happening? Any ideas on how this could be resolved?
Demo: http://83.212.101.132/angjs/ang4.html
This one is almost an exact duplicate of a similar question I had posted earlier, although the solution to this one seems to me rather far from obvious.
.slimScrollDiv SET overflow: visible;
.hbox, #content, .vbox AND following (if there are some) - remove z-index tag!
this was your mistake. Hope it works now, the adding on a Pane seem not to be implemented.
Because the JavaScript is modifying it I can't know for sure. However, my initial thoughts are it has to do with the z-index. The z-index for the center section is 99, and the lis are 0-10. Try making it update the z-index of the lis to 100+ on move.
I seems this remove position in left menu side and white drop box and set droppable menu z-index and position absolute may it works for you

Animated Scrolling with SuperScrollorama + Greensocks

I'm having a little trouble getting my head around a Javascript animated scroll issue.
I'm using the SuperScrollorama Jquery plugin which is built on-top of the Greensock JS tweening library.
The fundamental effect I'm after is to "pin" a section down, then use vertical scrolling to expand some content, then "unpin" the section once the content is fully expanded, so the user can scroll on - i.e. http://blueribbondesign.com.au/example/
But when I try to apply this same effect to multiple sections one after the other, everything gets all broken: the "unpinned" content below the pinned element is pushed off screen and it seems to miscalculate the height of the element when it performs the animation in reverse (i.e. scrolling back up the page). - i.e. http://blueribbondesign.com.au/example2/
I've been endlessly fiddling with the "position:fixed" and "pin-spacer" div, and tried attaching the Superscrollorama plugin to various containing elements, but still cannot work out how to get it to work.
Any help from the brilliant crowd-sourced minds of the web would be much appreciated,
Cheers,
TN.
I've been working with this issue myself. What happens is there's a blank div spacer put above the section being pinned with a height that you've defined in the pin() function. Secondly, the pinned element gets a position:fixed assigned to it. Both of these things allow the scroll bar to continue down the page while the element stays affixed. In turn, whatever you had below that section gets bumped down because of that spacer div's height.
If your pinned element is centered horizontally, first give it a left:50%, margin-left:-{width/2}px to fix it from pushing to the left edge.
Next, you'll have to detect the pin/unpin events (which are offered by the plugin as parameters additional to "anim"), and change the section underneath to also toggle a fixed/relative position. When you change that underlying section to be at a fixed position, be sure to set its "top" property to whatever the pinned element's height is. Once the pinned element becomes unpinned, change it back to relative positioning. Does that make any sense?
It seems that different techniques will call for different fixes, but those things are what I'd pay attention to... fixed positioning, and then using the pin/unpin events for adjustment.

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