I've created a sticky navbar for a subnav, which should stick at the top of the screen when the user scrolls down. Therefore I've tried some javascript, which changes the position to 'fixed' when the top is reached. Avoiding a gap in the content when the navbar is taken out of the flow, I've also added a placeholder, which has the same height as the navbar.
On Desktop it really works and looks how it should be. But I got a "touch" issue on mobile view. When I scroll down on mobile view the navbar will not appear during the process of scrolling over the viewpoint, where the css class is changing. It only appears when I stop scrolling after that viewpoint. When it shows up I can normally scroll up and down and I am only getting this issue again if I repeat this procedure, where the navbar has to change the css class. So it might be a problem with the css class change and I guess the problem could be in the javascript snippet. Does anybody know a solution for this? I'd like to have the same behavior like on desktop view, so the navbar is always visible and just fixed to the very top of the screen, even if it is in the flow of scrolling.
JS:
var menu = document.querySelector('#irp-localnav');
var menuPosition = menu.getBoundingClientRect();
var placeholder = document.createElement('div');
placeholder.style.width = menuPosition.width + 'px';
placeholder.style.height = menuPosition.height + 'px';
var isAdded = false;
window.addEventListener('scroll', function() {
if (window.pageYOffset >= menuPosition.top && !isAdded) {
menu.classList.add('sticky');
menu.parentNode.insertBefore(placeholder, menu);
isAdded = true;
} else if (window.pageYOffset < menuPosition.top && isAdded) {
menu.classList.remove('sticky');
menu.parentNode.removeChild(placeholder);
isAdded = false;
}
});
If you guess an error in the html/css markup, just let me know, so I get in touch with you again by posting this markup
Kind Regards
I was able to hack around. For anyone, who is facing a similiar issue:
Mobile browsers simply do not fire on a scroll event, while the event is in process. They fire when the event has stopped, so, when you've stopped scrolling. Using translate3d(0px,0px,0px) can solve this. Refer to this thread to read more about it:
iOS 9 Safari: changing an element to fixed position while scrolling won't paint until scroll stops
Kind Regards!
Related
I'm working on a new portfolio for myself, using Bootstrap framework and I want to animate my slider based on the direction that the user is scrolling.
For example I already have an animation to slide the navbar class in. But as the user scrolls down the page I want to hide the navbar this is to give the user more visibility on the screen when browsing content. Then when they attempt to scroll back up the page I want to slide the .navbar class back in again.
Now I can easily get this to work if I target a specific element or pixel height, but that doesn't help me. I know it's achievable as I've seen it on several websites (LinkedIn for example).
So I'm wondering if it's a case of targeting positive or negative values on the y axis or something?
var lastScrollPosition = 0;
window.onscroll = function() {
var newScrollPosition = window.scrollY;
if (newScrollPosition < lastScrollPosition){
//upward - code here
}else{
//downward - code here
}
lastScrollPosition = newScrollPosition;
}
Recently here, I asked a question to stick a bar element always to bottom-left of the container. It seems not possible using just css. So, I ended up using javascript. Here is the Working Fiddle
Giving highlights of the previous question:
Stick the bar element to bottom-left of the container
The bar should be in bottom-left, even the container is scrolled vertically or horizontally.
The bar should come over the horizontal scrollbar, if the horizontal scrollbar is present.
The above fiddle works fine and obeys all above cases, even when the window is resized.
Now, I have the same situation but the container will get resized because of animation button click but not window resize.
Since, I am animating for one second, I am calling the same code present in the window resize function while I clicked on the animating button. But doing so is somehow breaking and isn't following the above rules/requirements.
Here is the Fiddle. (not working)
Please help.
PS: Here is the link to previous question. (if someone wants brief understanding)
Again, I solved it. I was making things complicated. Where there was need of only bottom property, I was using top and resetting it. Lots of unneccessary action in the code.
Here is the code, which is working fine.
$(function () {
$('.content').width($('body').width() - 50);
});
var stickToBottom = function (parent) {
var bar = parent.querySelector('.bar');
var top = bar.offsetTop;
parent.addEventListener('scroll', function (e) {
var el = e.currentTarget;
bar.style.bottom = -el.scrollTop + "px";
bar.style.left = el.scrollLeft + "px";
});
}
var parent = document.querySelector('.parent');
stickToBottom(parent);
$('.clickme').click(function () {
$(this).toggleClass('active');
});
Thanks to rlemon for giving a idea in javascript chat room.
Working Fiddle
I would like to have a widget on a webpage containing a number of tabs. When the user scrolls the page and the widget comes in to view and he keeps scrolling down, the tabs should be activated one by one (without the page scrolling further down). Once the last tab is showing, the page should resume scrolling as usual. Is this doable using JS/jQuery?
UPDATE:
Since this seems too broad a question:
The problem is, I don't know how to use the scroll offset and prevent the page from scrolling down until I decide it can resume its normal behavior
UPDATE 2
I created This fiddle,
$(document).ready(function(){
$('#tabbed').mouseover(function(){
$(this).focus();
}).scroll(function(){
console.log("scrolling tabs");
});
$(window).scroll(function(evt){
var scrollPos = $(this).scrollTop()
console.log(scrollPos);
// BULLETPROOF WAY TO DETECT IF THE MOUSE IS OVER THE
// SCROLLABLE DIV AND GIVE IT FOCUS HERE?
});
});
it contains a long page and a scrollable div among its contents. The only problem is that the div starts catching scroll events only if I move my mouse. If I could find a bulletproof way to activate the scrolling div whenever the mouse is over it I'm there. Any ideas?
You can't prevent scrolling with javascript. Using iframes and divs with scroll will only work if the mouse is over them.
You can cancel the mouse wheel and keys events related to the scrolling, however the user will be able to scroll using the scrollbar (more here).
Another approach is leaving an empty area and fixing your widget inside this area, like in this working example
$(window).bind('scroll', function()
{
var scroll = $(window).scrollTop(),
innerHeight = window.innerHeight || $(window).height(),
fooScroll = $('#fooScroll'),
emptyArea = $('#emptyArea'),
offset = emptyArea.offset(),
fixedClass = 'fixed';
if(scroll > offset.top)
{
if(scroll < offset.top + emptyArea.height() - fooScroll.height())
{
fooScroll.addClass(fixedClass);
fooScroll.css("top", 0);
}
else
{
fooScroll.removeClass(fixedClass);
fooScroll.css("top", emptyArea.height() - fooScroll.height());
}
}
else
{
fooScroll.removeClass(fixedClass);
fooScroll.css("top", 0);
}
});
Then you can change the tabs while the page is scrolling.
You should be able to do this. You can use the jQuery scroll event to run your own code whenever the user scrolls up or down. Also, so long as you call e.preventDefault() whenever the scroll event is fired, you can prevent the whole window from scrolling up or down.
This question already has answers here:
Prevent scrolling of parent element when inner element scroll position reaches top/bottom?
(32 answers)
Closed 9 years ago.
I have a div that is scrollable, but whenever you reach the bottom/top of it, it begins to scroll the entire page. That could be annoying for users who scroll fast, and then the entire page starts scrolling unexpectedly.
I need something where if you are hovering over the div, the page is not scrollable.
I have tried this by adding CSS when I hover the div...
body {
overflow:hidden;
}
...It works but there is one problem. The scrollbar disappears and that looks kind of stupid to have it disappearing/reappearing. Any way to achieve the same effect but keep the scrollbar visible? I have seen it done with Facebook chat.
Here is a very simple way to stop the propagation with no plugins, just jQuery.
Update: The code has been updated to work correctly in IE9+. Have not tested in previous versions.
First, create a class on your <div> to mark it as having this behavior. In my example, I use the class .Scrollable.
<div class="Scrollable">
<!-- A bunch of HTML here which will create scrolling -->
</div>
The jQuery to disable is:
$('.Scrollable').on('DOMMouseScroll mousewheel', function(ev) {
var $this = $(this),
scrollTop = this.scrollTop,
scrollHeight = this.scrollHeight,
height = $this.height(),
delta = (ev.type == 'DOMMouseScroll' ?
ev.originalEvent.detail * -40 :
ev.originalEvent.wheelDelta),
up = delta > 0;
var prevent = function() {
ev.stopPropagation();
ev.preventDefault();
ev.returnValue = false;
return false;
}
if (!up && -delta > scrollHeight - height - scrollTop) {
// Scrolling down, but this will take us past the bottom.
$this.scrollTop(scrollHeight);
return prevent();
} else if (up && delta > scrollTop) {
// Scrolling up, but this will take us past the top.
$this.scrollTop(0);
return prevent();
}
});
In essence, what this does is to detect which direction the scrolling is being requested in (based on the originalEvent.wheelDelta: positive = up, negative = down). If the requested delta of the mousewheel event would move scrolling past the top or bottom of the <div>, cancel the event.
In IE, especially, scrolling events which go past a child element's scrollable area then roll up to parent elements, and the scrolling continues regardless of the event being canceled. Because we cancel the event in any case, and then control the scrolling on the child through jQuery, this is prevented.
This is loosely based on the way that this question solves the problem, but does not require the plugin, and is cross-browser compliant with IE9+.
Here is a working jsFiddle demonstrating the code in-action.
Here is a working jsFiddle demonstrating the code in-action, and updated to work with IE.
Here is a working jsFiddle demonstrating the code in-action, and updated to work with IE and FireFox. See this post for more details about the necessity of the changes.
maybe have a look to
How to disable scrolling temporarily?
This is a sample to stop and activate scroll
I have been having the oddest bug in firefox. I have a parent div (divbodycontainer) that is having its content scrolled down the screen when a child div containing a floated div with a base height of 0 is dynamically scrolled using javascript. If you scroll half way down any of the main pages in firefox and refresh the page the parent divs content will jump down. Odd thing is firebug reports no css or code change that could be doing this?
Bug also randomly pops up during fast scrolling.
Tried to fix bug by adding a height style to the javascript function since the bug is tied to the scrolling action.
$(window).scroll(function () {
var ntMin = 0+"px";
var newTop = $(window).scrollTop();
if (newTop <= ntMin){
newTop = ntMin;
}
$("#floatPitchButton").stop()
.animate({'top': newTop}, "slow")
document.getElementById('floatPitchButton').style.height = ntMin;
});
This idea did not fix my problem? Anyone have any idea whats going on?
Site: www.webstudioproductions.com
It looks like I was able to solve the problem by deleting the server js file and re-ftping the file.