I have a div that follows the browser as it scrolls and is contained within another div.
The following function keeps my div in place and moving when the user scrolls:
$(function() {
var offset = $("#sidebar").offset();
var topPadding = 15;
$(window).scroll(function() {
if ($(window).scrollTop() > offset.top) {
$("#sidebar").stop().animate({
marginTop: $(window).scrollTop() - offset.top + topPadding
});
} else {
$("#sidebar").stop().animate({
marginTop: 0
});
};
});
});
This works pretty well, except when the browser height is less than 400px, then it gets buggy.
So I thought I'd include a simple line to get it to only run when the browser is >=400 as such:
if (window.innerHeight >= 400) {
$(function() {
var offset = $("#sidebar").offset();
var topPadding = 15;
$(window).scroll(function() {
if ($(window).scrollTop() > offset.top) {
$("#sidebar").stop().animate({
marginTop: $(window).scrollTop() - offset.top + topPadding
});
} else {
$("#sidebar").stop().animate({
marginTop: 0
});
};
});
});
}
This seems to work fine so long as the initial browser height is greater than 400px. If the browser window is resized from it's initial height, the code will still execute, which is counter to what I want.
Essentially, is there a way to dynamically track the browser size and only run this code when the height is larger than 400px and not run when less than 400px?
Thanks for any help!
Just move the check into your event handler:
$(function() {
var offset = $("#sidebar").offset();
var topPadding = 15;
$(window).scroll(function() {
if (window.innerHeight >= 400) { // <=== Moved it here
if ($(window).scrollTop() > offset.top) {
$("#sidebar").stop().animate({
marginTop: $(window).scrollTop() - offset.top + topPadding
});
} else {
$("#sidebar").stop().animate({
marginTop: 0
});
}
}
});
});
Now the check is done when you're processing the scroll event, rather than just once at the outset preventing the scroll from being hooked at all.
Separately, because you're doing this on the scroll event, which happens pretty often, I'd try to minimize the number of times you wrap or look up elements. Instead of doing it on every event, since window isn't going to change and I suspect your sidebar isn't going to change either, wrap/look them up once:
$(function() {
var offset = $("#sidebar").offset();
var topPadding = 15;
var sideBar = $("#sidebar");
var $window = $(window);
$window.scroll(function() {
if ($window.height() >= 400) { // <=== Moved it here
if ($window.scrollTop() > offset.top) {
sidebar.stop().animate({
marginTop: $window.scrollTop() - offset.top + topPadding
});
} else {
sidebar.stop().animate({
marginTop: 0
});
}
}
});
});
That also makes it reasonable to use jQuery's height function on window for cross-browser compatibility.
To track the browser width & height as it is being resized:
$(window).resize(function()
{
var viewportWidth = $(window).width();
var viewportHeight = $(window).height();
// More code here...
};
However, I think there is a better way to keep your div in place, one that does not involve Javascript. Have you tried using position:fixed?
Related
I know there's a pretty simple way of doing this, but I can't seem to find anything in my searches.
I've found lots of examples of getting to a certain scroll location on the page and then animating a div to a different size, however I want to adjust a div's max height depending on the scroll location. Initially i'd like the div max-height to be about 150px, and then as you scroll from around 200px down the page to 400px down the page, I want the max-height of the div to decrease to 75px. Then obviously as you scroll back up, it gets larger.
I can't provide an example of what I've tried already, as I'm yet to attempt it as I have no idea on where to start.
Note: The size should gradually adjust with the scroll position.
I'm not sure if I understood your problem, but when I did I came out with this :D
$(window).scroll(function(){
var scrollTop = $(window).scrollTop();
if(scrollTop < 200){
maxHeight = 150;
}else if(scrollTop > 400){
maxHeight = 75;
}else{
maxHeight = 150 - 75 * (((scrollTop-200) * 100)/200)/100;
}
$('#thediv').stop().animate({'max-height': maxHeight+"px"}, 500);
})
Here you have a sample : https://jsfiddle.net/keccs4na/
You could try this:
$(window).on('scroll', function() {
var scrollTop = $(window).scrollTop();
if (scrollTop >= 200 && scrollTop <= 400) {
$('#divID').stop().animate({height: "75px"}, 250);
} else {
$('#divID').stop().animate({height: "150px"}, 250);
}
});
Note: You'll want to use CSS to initially set the height to 150px.
Try this.
$(window).on('scroll', function () {
var v = $(window).scrollTop();
if (v > 200) {
$('#id-of-div').css({"height": "75px","max-height":"75px"});
}
else {
$('#id-of-div').css({"height": "150px","max-height":"150px"});
}
});
EDIT:
$(window).on('scroll', function () {
var v = $(window).scrollTop();
if (v > 200) {
$('#id-of-div').animate({"height": "75px","max-height":"75px"},500);
}
else {
$('#id-of-div').animate({"height": "150px","max-height":"150px"},500);
}
});
I have a sidebar that scrolls down with the page. However, the sidebar seems to lag behind the scrolling of the page, ex. scroll down and sidebar shows up a few seconds later. Also, the sidebar will keep going down, making the page longer, and causing the footer to become inaccessible. What do I need to do to make the sidebar move with the scroll and for the sidebar to stop moving at the footer? Here is my jQuery code:
$(function() {
var $sidebar = $("aside"),
$window = $(window),
offset = $sidebar.offset(),
topPadding = 50;
$window.scroll(function() {
if ($window.scrollTop() > offset.top) {
$sidebar.stop().animate({
marginTop: $window.scrollTop() - offset.top + topPadding
});
} else {
$sidebar.stop().animate({
marginTop: 0
});
}
});
});
An example can be seen at http://meddiary.com/plans-pricing/. Fixing the code is welcomed but just pointing me in the right direction is the best.
Try solving it with pure CSS:
.affix {
position: fixed;
}
Or you can use an existing jQuery plugin like this one:
http://andrewhenderson.me/tutorial/jquery-sticky-sidebar/
This is how I fixed my issue:
if ($(window).width() > 767) {
var $sidebar = $("aside"),
$window = $(window),
offset = $sidebar.offset(),
topPadding = 50;
$window.scroll(function() {
if($window.scrollTop() > $('h3').offset().top) {
$sidebar.stop().css('marginTop', '680px');
} else if ($window.scrollTop() > offset.top) {
$sidebar.stop().animate({
marginTop: $window.scrollTop() - offset.top + topPadding
}, 100, function() {
});
} else {
$sidebar.stop().animate({
marginTop: 0
});
}
});
};
if ($(window).width() > 767) part keeps the sidebar from scrolling if the viewport is wider than 767px. if($window.scrollTop() > $('h3').offset().top) { $sidebar.stop().css('marginTop', '680px'); } part is for when the top of the viewport hits the desired element, h3, the scrolling stops. That part must be first because the else if statement is always true! Then I just reduced the animation time to stop the lagging.
I'm building a website. http://check.topicwine.com
Have a look to see my work.
I want to make a static sidebar. I'm using the code:
$(function() {
var offset = $("#ad-wrapper").offset();
var topPadding = 60;
$(window).scroll(function() {
if ($(window).scrollTop() > offset.top) {
$("#ad-wrapper").stop().animate({
marginTop: $(window).scrollTop() - offset.top + topPadding
});
} else {
$("#ad-wrapper").stop().animate({
marginTop: 0
});
};
});
});
The sidebar comes along, but it also goes where it shouldn't. I mean, it enters the footer as well. Rather, it overlaps the footer.
I want it to stop next to the grid.
Thanks, in advance. :)
Add overflow:hidden to div#content. This way we will get the proper height of the content div.
Now $('#content').height() + $('#content').offset().top is the maximum distance the sidebar should move. Which means, the sidebar's offset.top + height should not go more than this.
Add this check in your scroll handler
Set a limit for the top margin, since the sidebar can't go past the $('#main') element.
$(function() {
var offset = $("#ad-wrapper").offset();
var topPadding = 60;
$(window).scroll(function() {
var scrollTop = $(window).scrollTop(); // Store this for convenience
if (scrollTop > offset.top) {
var newMarginTop = scrollTop - offset.top + topPadding;
// The sidebar can only go so far!
var marginLimit = $('#main').height() + $('#main').offset().top - offset.top - $("#ad-wrapper").height();
if (newMarginTop > marginLimit)
newMarginTop = marginLimit;
$("#ad-wrapper").stop().animate({
marginTop: newMarginTop
});
} else {
$("#ad-wrapper").stop().animate({
marginTop: 0
});
}
});
});
While scrolling, I want to fire an event 300px before the end of the document.
Say the height of my HTML document is 1000px and the height of the window viewport is 600px, on scrolling 100px down, the event should be fired.
I've this code
$(window).scroll(function(){
if ($(window).scrollTop() == $(document).height() - $(window).height() ){
callFunction();
}
});
This fires the event when the scroll has reached the bottom. So I modified it as
$(window).scroll(function(){
var height = $(window).height() + 300;
if ($(window).scrollTop() == $(document).height() - height ){
callFunction();
}
});
But obviously, it seems to be wrong since it doesn't work. Please Help.
var down = $(window).height() + 300;
if ($(window).scrollTop() > $(document).height() - down){
try this one
Working demo
I think the problem you are having is that the scrollTop will never have exactly the right pixel value you are looking for. Your math is correct but use a > instead of == and you should be more successful.
$(window).scroll(function(){
var height = $(window).height() + 300;
if ($(window).scrollTop() > $(document).height() - height ){
callFunction();
}
});
I had to modify your script a bit but here is an example:
var invoked = false;
var height = $(document).height() - 300 - $(window).height();
$(window).scroll(function(){
if ($(window).scrollTop() >= height && !invoked ){
invoked = true; // don't call this twice
alert('foo');
callFunction();
}
});
I have a sort of sidebar on my website, which has to scroll down together with the user so that it is always in the view.
The code I'm using now is actually working fine however there is one problem. On smaller screens the sidebar scrolls before your at the sidebar thus making it impossible to see it all even if you scroll.
So what I want is the sidebar to scroll with the bottom instead of it being pushed down with the top so that when you reach the end of the sidebar it starts to scroll.
This is the code that I'm currently using.
var documentHeight = 0;
var topPadding = 10;
$(function() {
var offset = $("#mainright").offset();
documentHeight = $(document).height();
$(window).scroll(function() {
var sideBarHeight = $("#mainright").height();
if ($(window).scrollTop() > offset.top) {
var newPosition = ($(window).scrollTop() - offset.top) + topPadding;
var maxPosition = documentHeight - (sideBarHeight);
if (newPosition > maxPosition) {
newPosition = maxPosition;
}
$("#mainright").stop().animate({
marginTop: newPosition
});
} else {
$("#mainright").stop().animate({
marginTop: 0
});
};
});
});
I guess the "best practice" for accomplishing a task like this is to use dynamically changing css position from absolute to fixed and vice versa. A basic example could look like:
$(function(){
var $box = $('.box'),
offset = $box.offset(),
doc_h = $(document).height();
$(window).scroll(function(){
if($(window).scrollTop() > offset.top) {
if(!$box.hasClass('fix'))
$box.toggleClass('normal fix');
}
else{
if(!$box.hasClass('normal'))
$box.toggleClass('normal fix');
}
});
});
Example in action: http://www.jsfiddle.net/YjC6y/14/
$(function() {
var top = 50;
$(window).scroll(function() {
$('#box').stop().animate({ top: $(window).scrollTop() + top}, 1000);
});
});
Try the example : http://jsbin.com/omiyi3
I think you can instead make the sidebar responsive by throwing your function into one of these:
if (responsive_viewport >= 768) {}
This makes it so that the function will only load if the viewport is bigger than or equal to 768px.