Develop Reference

Sticky remove on mobile screen

I have done topbar sticky on desktop view with the help of Jquery but I don't want a sticky top bar on a mobile screen during scroll.
I did topbar sticky with this code:
$(document).ready(function(){
$(window).scroll(function(){
var sticky = $('#top-header'),
scroll = $(window).scrollTop();
if (scroll >= 100) {
sticky.addClass('fixed');
} else {
sticky.removeClass('fixed');
}
});
});

You should modify your condition statement:
if ((scroll >= 100) && ($(window).width() > /* Mobile screen width */)) {
sticky.addClass('fixed');
}

You can add media query using css or you can define screen width for your jQuery code.
if($(window).width() > 767){
$(document).ready(function(){
$(window).scroll(function(){
var sticky = $('#top-header'),
scroll = $(window).scrollTop();
if (scroll >= 100) {
sticky.addClass('fixed');
} else {
sticky.removeClass('fixed');
}
});
});
}

use this code and you also need one more condition for mobile device width. using this code you can remove the "fixed" class on resize also.
$(document).ready(function(){
$(window).on('scroll resize',function(){
var sticky = $('#top-header');
var scrollTop = $(document).scrollTop();
var windowWidth = $(window).width();
if(scrollTop >= 200 && windowWidth >= 768){
sticky.addClass('fixed');
}else {
sticky.removeClass('fixed');
}
});
});

Show and hiding div after scroll point

I am using this script to hide a div and show it when have scrolled past a certain point in the page. This is working fine, but when I scroll back up to the top, the div then stays visible. Could anyone help me with an amendment I can make to the code to hide the div again when scrolling back above the desired point?
Thanks, T
$(document).ready( function() {
$("#dvid").hide(); //hide your div initially
var topOfOthDiv = $("#othdiv").offset().top;
$(window).scroll(function() {
if($(window).scrollTop() > topOfOthDiv) { //scrolled past the other div?
$("#dvid").show(); //reached the desired point -- show div
}
});
});

$(document).ready( function() {
$("#dvid").hide(); //hide your div initially
var topOfOthDiv = $("#othdiv").offset().top;
$(window).scroll(function() {
if($(window).scrollTop() > topOfOthDiv) { //scrolled past the other div?
$("#dvid").show(); //reached the desired point -- show div
}
else{
$("#dvid").hide(); //else above the desired point -- hide div
}
});
});

$(document).ready( function() {
$("#dvid").hide(); //hide your div initially
var topOfOthDiv = $("#othdiv").offset().top;
$(window).scroll(function() {
if($(window).scrollTop() > topOfOthDiv) { //scrolled past the other div?
$("#dvid").show(); //reached the desired point -- show div
} else {
$("dvid").show(); //hide div
}
});
});

First, check the element visibility:
var rect = element.getBoundingClientRect();
var visible = Boolean(
rect.top >= 0
&& rect.left >= 0
&& rect.bottom <= (window.innerHeight || document.documentElement.clientHeight)
&& rect.right <= (window.innerWidth || document.documentElement.clientWidth)
);
Then bind event to revalidate visibility:
jQuery(window).bind('DOMContentLoaded load resize scroll', fn);
// fn - is your function to show/hide elements in accordance with previous statement
So, the final code would be:
$(document).ready( function() {
var checkVisibility = function () {
$("#dvid, #othdiv").each(function () {
var rect = this.getBoundingClientRect(),
visible = Boolean(
rect.top >= 0
&& rect.left >= 0
&& rect.bottom <= (window.innerHeight || document.documentElement.clientHeight)
&& rect.right <= (window.innerWidth || document.documentElement.clientWidth)
);
$(this)[visible ? 'show' : 'hide']();
});
};
//hide your divs initially
$("#dvid, #othdiv").hide();
jQuery(window).bind('DOMContentLoaded load resize scroll', checkVisibility);
});

Disabling Mousewheel JS horizontal scroll under certain screen size

I'm using .mousewheel to translate my downwards scroll into horizontal scroll on desktop, however for mobile I want to disable this behavior. I have tried the following:
if ( $(window).width() > 480) {
$('html, body, *').mousewheel(function(e, delta) {
this.scrollLeft -= (delta * -0.5);
e.preventDefault();
});
}
else {
$("html, body, *").bind("mousewheel", function() {
return false;
});
}
But no success, the horizontal scrolling works fine but the body content is still locked in place on mobile.

To get the viewport width:
var viewportWidth = Math.max(document.documentElement.clientWidth, window.innerWidth || 0)
Then you can just make a small change to your if statement:
if (viewportWidth > 480) { ... }
Full code example
This includes a little "fix-up" with the way that the scroll translation was happening - I couldn't get the previous way to work.
var viewportWidth = Math.max(document.documentElement.clientWidth, window.innerWidth || 0);
if (viewportWidth > 480) {
$('body').mousewheel(function(e) {
$(this).scrollLeft($(this).scrollLeft() - e.deltaY);
e.preventDefault();
});
} else {
$("body").on("mousewheel", function() { return false; });
}

Building an animated menu with Jquery that responds to page scrolling

Sorry for the terrible title, but I'm not sure how else to describe what I'm trying to build. I'm using some code I found on this site, basically what I'm trying to do is build a left handed navigation menu, that highlights the appropriate section as the user scrolls to it.
$(document).ready(function() {
var topRange = 200, // measure from the top of the viewport to X pixels down
edgeMargin = 20, // margin above the top or margin from the end of the page
animationTime = 600, // time in milliseconds
contentTop = []; //array of sidebar links
$('nav ul').append('<div id="slider"></div>');
var sliderTop = $("nav ul li a").eq(0).parent().position().top;
var sliderLeft = $("nav ul li a").eq(0).parent().position().left;
var sliderHeight = $("nav ul li a").eq(0).parent().outerHeight();
$('#slider').css({
'height': sliderHeight,
'left': sliderLeft,
'top': sliderTop,
'width': '100%'
});
// Stop animated scroll if the user does something
$('html,body').bind('scroll mousedown DOMMouseScroll mousewheel keyup', function(e) {
if (e.which > 0 || e.type == 'mousedown' || e.type == 'mousewheel') {
$('html,body').stop();
}
})
// Set up content an array of locations
$('#sidebar').find('a').each(function() {
contentTop.push($($(this).attr('href')).offset().top);
})
// Animate menu scroll to content
$('#sidebar').find('a').click(function() {
var sel = this,
newTop = Math.min(contentTop[$('#sidebar a').index($(this))], $(document).height() - $(window).height()); // get content top or top position if at the document bottom
$('html,body').stop().animate({
'scrollTop': newTop
}, animationTime, function() {
window.location.hash = $(sel).attr('href');
});
return false;
})
//scroll function
function scroller() {
var winTop = $(window).scrollTop(),
bodyHt = $(document).height(),
vpHt = $(window).height() + edgeMargin; // viewport height + margin
$.each(contentTop, function(i, loc) {
if ((loc > winTop - edgeMargin && (loc < winTop + topRange || (winTop + vpHt) >= bodyHt))) {
//animate slider
x = $("#sidebar li").eq(i).position();
$("#slider").animate({
top: (x.top)
}, 100);
}
})
}
//scroll event handler
$(window).scroll(scroller)
})
I have most of it working, however when you actually click a link on the menu the animation is very slow to catch up with the actual scrolling. I understand why this is happening, because it updates the position one at a time after each section is reached, but I'm wondering if there's a way to make this animation faster, and more fluid. I've attached a fiddle with my code, thank you in advance for your help!
http://jsfiddle.net/jamesmyers/6mbmq1pe/

You will get a better slider animation effect by temporarily detaching the scroll handler and scrolling the slider directly, with the same animationTime as for the main animation.
To do this, you also need to :
namespace the scroll event .nav, to allow safe use of .off()
stop() the slider animation in the "if the user does something" block
I've also included a few efficiency savings in the way contentTop and #slider are set up but these are not actually necessary.
$(document).ready(function() {
var topRange = 200, // measure from the top of the viewport to X pixels down
edgeMargin = 20, // margin above the top or margin from the end of the page
animationTime = 600, // time in milliseconds
contentTop, //array of sidebar links
navLinkWrapper = $("nav ul li a").eq(0).parent();
var $slider = $("<div id=\"slider\" />").css({
'height': navLinkWrapper.outerHeight(),
'left': navLinkWrapper.position().left,
'top': navLinkWrapper.position().top,
'width': '100%'
}).appendTo($('nav ul'));
// Stop animated scroll if the user does something
$('html,body').on('scroll mousedown DOMMouseScroll mousewheel keyup', function(e) {
if (e.which > 0 || e.type == 'mousedown' || e.type == 'mousewheel') {
$('html,body').stop();
$slider.stop(); //<<<<<<<
}
});
// Set up content an array of locations
contentTop = $('#sidebar a').map(function() {
return $($(this).attr('href')).offset().top;
});
// Animate menu scroll to content
$('#sidebar a').on('click', function(e) {
e.preventDefault();
$(window).off('scroll.nav', scroller); //<<<<<<<
$slider.stop().animate({ //<<<<<<<
top: ($(this).closest("li").position().top) //<<<<<<<
}, animationTime); //<<<<<<<
var sel = this,
newTop = Math.min(contentTop[$('#sidebar a').index($(this))], $(document).height() - $(window).height()); // get content top or top position if at the document bottom
$('html,body').stop().animate({
'scrollTop': newTop
}, animationTime, function() {
window.location.hash = $(sel).attr('href');
$(window).on('scroll.nav', scroller); //<<<<<<<
});
});
//scroll function
function scroller() {
var winTop = $(window).scrollTop(),
bodyHt = $(document).height(),
vpHt = $(window).height() + edgeMargin; // viewport height + margin
$.each(contentTop, function(i, loc) {
if ((loc > winTop - edgeMargin && (loc < winTop + topRange || (winTop + vpHt) >= bodyHt))) {
//animate slider
$slider.animate({
top: ($("#sidebar li").eq(i).position().top)
}, 100);
}
});
}
//scroll event handler
$(window).on('scroll.nav', scroller); //<<<<<<<
});
Updated fiddle

Animate element on scroll

I would like to animate a div when user scrolls the page.
For that, i implemented this code:
var slide = jQuery(".apresentacao-spc-01");
var opening = false;
var closing = false;
var pos = jQuery(window).scrollTop();
jQuery(window).scroll(function() {
var pos = jQuery(window).scrollTop();
console.log(pos);
if (pos > 100) {
if (!opening) {
opening = true; closing = false;
slide.stop().animate({
'opacity': 1,
'margin-left': '0px'
}, 700, function() {
opening = false;
});
}
} else {
if (!closing) {
closing = true; opening = false;
slide.stop().animate({
'opacity': 0,
'margin-left': '-1000px'
}, 500, function() {
closing = false;
});
}
}
});
The issue is:
Using "if (pos > 100) {", if the user resolution is big enough to show the element before he needs to scroll, he won't see the element unless he begins to scroll the page.
My question is:
How can I get a scroll animation that will be executed when the element is visible?
I mean: If the element is visible on page load, the animation automatically starts... If the element is not visible on page load, the animation waits the scroll reach the element to start...
Thanks.

There a few different things you could do. My first thought was to query the height of the viewport with something like this:
var viewportWidth = document.documentElement.clientWidth
, viewportHeight = document.documentElement.clientHeight
And then trigger the animation if it is taller than the distance the element is down.
A more dynamic solution would be to use a function that checks to see if the element is in viewport the automatically, that way you wouldn't need to worry about adjusting the height if you changed stuff on your page:
function isElementInViewport (el) {
var rect = el.getBoundingClientRect();
return (
rect.top >= 0 &&
rect.left >= 0 &&
rect.bottom <= (window.innerHeight || document.documentElement.clientHeight) && /*or $(window).height() */
rect.right <= (window.innerWidth || document.documentElement.clientWidth) /*or $(window).width() */
);
}
credit to this response.
There is a use guide and further information in the link provided.
Good luck!