Is it possible via Javascript to store how far a user has scrolled while on page (pixel-wise), regardless of where they are at any time?
For example, I'd like to track how far someone scrolled before going back up to do a specific action at the top of the page.
Thanks!
Simply save the scroll position if it's the lowest one, every time a scroll happens.
var maxScroll = 0;
$(window).scroll(function () {
var scroll = $(document).scrollTop();
if (scroll > maxScroll) maxScroll = scroll;
});
// maxScroll is at any time the lowest point of vertical scrolling on the page.
You might want to debounce the handler for better performance.
Related
I need to implement a scroll function in my site.
When I will scroll down, document will be scrolled until a fixed position, which I want.
For example:
$(“.scroll-block”).scrollTop(250);
I realized this function. Pseudo-code:
when (scrollTop > 0)
do (scrollTop(250))
But then scroll is fixed. And any scroll-actions doesn’t work.
But I have three block. And I want to keep the possibility to scroll to all three blocks.
How can I do that?
P.S.: sorry for my terrible English. It’s my first post on this platform for communication.
P.S.S.: and first topic on English language.
Register a scroll callback like so:
jQuery(window).scroll(scrollCallback);
In the callback you can get the scroll position and do whatever you want at specific heights.
function scrollCallback(){
//gets the current windows scroll top value
var scrollPos = jQuery(window).scrollTop();
//get the position of the top of the elements you want to trigger actions on.
var first = jQuery('the-element-you-want-to-select1').position().top;
var second = jQuery('the-element-you-want-to-select2').position().top;
if(scrollPos > first){
//do something for first height
}else if(scrollPos > second){
//do something for second height
}
..
..
}
Hi Guys,
I'm not so good with jQuery and javascript.
I will make a script that take the position of my div and when it's on the top of the page it make something.
Example:
I have a menu. When i scroll the page and my div arrive at the top (or better at 100/200px from top), something in my menu changes...
I hope somebody can help me.
Thanks.
You should use the jQuery offset() scrollTop() and scroll() methods to achieve this.
http://api.jquery.com/offset/
https://api.jquery.com/scrollTop/
https://api.jquery.com/scroll/
Offset returns the pixel value of the elements from the top of the page. Run this on scroll, and you can detect when the element is 100px, or 200px from the top.
Here is an example of running offset() and scrollTop() on window.scroll(), and adding/removing classes when the element has reached the top of this page. In this example, I am fixing the $mainMenuBar to the top of the page when the user scrolls past it, and un-fixing it when the user scroll back up past it.
// declare vars
var $window = $(window),
$mainMenuBar = $('.anchor-tabs'),
$mainMenuBarAnchor = $('.anchor-tabs-anchor');
// run on every pixel scroll
$window.scroll(function() {
var window_top = $window.scrollTop();
var div_top = $mainMenuBarAnchor.offset().top;
if (window_top > div_top) {
// Make the div sticky.
$mainMenuBar.addClass('fixed-top');
$mainMenuBarAnchor.height($mainMenuBar.height());
}
else {
// Unstick the div
$mainMenuBar.removeClass('fixed-top');
$mainMenuBarAnchor.height(0);
}
});
Hope this helps.
You can compare the offset of your div element to how far down the page the user has scrolled.
The $(window).scrollTop() function get you how far the user has scrolled down, i.e :
$(window).scroll(function() {
var yourDiv = $("#theIdOfYourDiv");
var window_offset = yourDiv.offset().top - $(window).scrollTop();
if ( window_offset < 100 )
{
// do what you want
}
});
I have a code
var scroll = $(window).scrollTop();
$(window).on("scroll", function () {
scroll+=100;
$(window).scrollTop(scroll); //*
})
But this code scroll the window with a loop to the bottom. how to make something like throttle in order to avoid the recursion ?
The goal: i have the 404 page and iframe with index page below of 404. and when user try to scroll 404 page - index pages scroll to top with doubled speed
To Solve your issue I took a slightly different approach, upon scroll I am scrolling to the Index location only once.
var $window = $(window);
var indexLocation = 505;
$window.one("scroll", function(e){
if ($window.scrollTop() < indexLocation){
$("body").animate({scrollTop: indexLocation});
}
});
Also you can check it out here: http://jsfiddle.net/jsJJK/1/
fiddle: http://jsfiddle.net/DerNalia/88N4d/9/
The behavior I'm trying to accomplish:
The Sidebar(s) should be fixed on the page if there is enough room
for them
The Sidebar(s) should scroll if there is ever not enough room for them
When scrolling down, and the bottom of the sidebar(s) is reached, it should stop scrolling
When scrolling down, the sidebar(s) should also scroll down, until
the bottom of the sidebar(s) is/are reached
When scrolling up, and the top of the sidebar(s) is reached, it should stop scrolling
If at any point during the scrolling of the content, the user switches directions of scrolling, the sidebar(s) shall also move in the same direction as the rest of the page / content
When scrolling up, the sidebar(s) should also scroll up, until the
top of the sidebar(s) is/are reached
If the content is shorter than the sidebar(s), the sidebar(s) should
still be able to scroll This is the one that I'm having trouble
with
How do I make it so that I can detect the intended scroll distance desired by the user, rather than use the actual scrolled distance of the content body? There may be another solution, but this is all I can think of for right now.
I'm currently using Chrome on Mac.
UPDATE:
something I've noticed: using the track pad on macs does the stretching / bouncy scrolling shenanigans on the edges.. which messes up this javascript hard core. It's possible to scroll the sidebar completely off the screen if you bounce up enough times. Mouse Wheel scrolling does not have this issue.
I think you’d be much better off positioning the columns absolute and then check positions onscroll and toggle the positions.
It gets quite complicated, since the scroll will jump if both columns are fixed and the content has regular flow.
I created a solution for you using a simpler logic that goes:
var $win = $(window);
var $containers = $(".container").css('position','absolute');
// we need to force a height to the body for fixed positioning
$('body').css('minHeight', Math.max.apply( Math, $containers.map(function() {
return $(this).height();
})));
$win.bind("resize scroll", function() {
var scrolled = $win.scrollTop(),
winheight = $win.height(),
elheight = 0;
$containers.each(function() {
elheight = $(this).height();
$(this).css('position', function() {
if ( elheight > (winheight+scrolled) ) {
$(this).css('top',0);
return 'absolute';
}
$(this).css('top', Math.min(0, winheight-elheight));
return 'fixed';
});
});
});
It should fill your requirements. The fixed positioning kicks in if the columns are shorter than the window height, or if the scrollTop is enough.
A demo in all it’s glory: http://jsfiddle.net/mb9qC/
I am using the excellent jQuery Reel plugin (http://jquery.vostrel.cz/reel) for a project. I would like to bind to the window scroll event, so when the user scrolls down the page the plugin advances 1 frame for say every 10px scrolled, if the user scrolls up the animation is reversed.
The plugin has methods I can pass the values to no problem and I know how to bind to the window scroll event. What I am struggling with is the last.
How can I use jQuery/JavaScript to say for every 10 pixels scrolled in any vertical direction advance 1 frame in the animation? I know I can store the window scroll in a variable but I'm unsure how to say every time it hits a multiple of 10 advance one frame.
Many thanks in advance.
EDIT
Thanks to help of the users below I worked out a solution. As follows:
$(window).scroll(function()
{
windowScrollCount = $(this).scrollTop();
animationFrame = Math.round(windowScrollCount / 100);
});
So here I am getting the scrolled distance in windowScrollCount, translating it into frames in animationFrame and setting it back with .reel("frame", animationFrame); I am actually doing this for every 100 frames as every 10 was to quick.
Thanks to help of codef0rmer and noShowP I worked out a solution. As follows:
$(window).scroll(function()
{
windowScrollCount = $(this).scrollTop();
animationFrame = Math.round(windowScrollCount / 100);
});
So here I am getting the scrolled distance in windowScrollCount, translating it into frames in animationFrame and setting it back with .reel("frame", animationFrame); I am actually doing this for every 100 frames as every 10 was to quick.
If I'm wrong then you might want this:
var jump = 500; // consider this is your 10px
window.scrollHeight = 0;
$(window).scroll(function () {
console.log($(this).scrollTop());
var diff = $(this).scrollTop() - window.scrollHeight;
if (diff >= jump) {
window.scrollHeight = $(this).scrollTop();
console.log('reload frame');
}
});
Demo : http://jsfiddle.net/Dyd6h/
You could possible have a sticky element to the top of your page,
position: fixed; top 0; left: 0;
(hidden if you like).
And then when you are scrolling you can monitor its offset:
$('element').offset().top
You can then see how far down the page you have scrolled, so every time they scroll see what its top value is and trigger events appropiately?
EDIT:
I've set up a little JSfiddle with a start of what I think you need.
http://jsfiddle.net/qJhRz/3/
Im just calculating the frame you need to be on and storing that in a variable. Is it anything like what you're looking for?