jQuery Scroll Current Position and Next-Prev Navigator - javascript

I need a bit of advice as I can't get my noob head around the following, please see this fiddle: http://jsfiddle.net/NtUpw/
The code works as intended, but when the current div offset goes > 41 and prev is hit, I'd like the page to return to the beginning of the current div, not to one before that. Any idea how can I add this condition?
I realise the current code isn't the cleanest (actually it's a combination of two fiddles), but I hope someone could take a look at it anyway. Thanks.
$('a.buttons').on('click', function (e) {
e.preventDefault();
var t = $(this).text(),
that = $(this);
if (t === 'next' && $('.current').next('div.post').length > 0 ) {
var $next = $('.current').next('.post');
var top = $next.offset().top;
$('body').animate({
scrollTop: $('.current').next('div.post').offset().top - 40
});
} else if (t === 'prev' && $('.current').prev('div.post').length > 0 ) {
var $prev = $('.current').prev('.post');
var top = $prev.offset().top;
$('body').animate({
scrollTop: $('.current').prev('div.post').offset().top - 40
});
}
$(window).bind('scroll', function () {
$('.post').each(function () {
var post = $(this);
var position = post.position().top - $(window).scrollTop();
if (position <= 40) {
post.addClass('current');
post.prev().removeClass("current");
} else {
post.removeClass('current');
}
});
});

The prev action works by moving always the div to the previous; the solution is to check the current position of the navigator respect to the current div:
var $prev;
var top;
var firstElem = true;
if ($('.current').prev('div.post').length > 0) {
$prev = $('.current').prev('.post');
top = $prev.offset().top;
firstElem = false
}
var currTop = $('.current').offset().top;
var navBottom = $('.navigation').offset().top + 40;
if (currTop == navBottom && !firstElem) {
$('body,html').animate({
scrollTop: $('.current').prev('div.post').offset().top - 40
});
with this the navigator jumps to the previous div only if is not at the top of the current; alternatively jumps to the previous.
The firefox issue depends on how Firefox places the overflow, it places it at the html level not at body like other browsers.
To let it work you must define the scrolling action with:
$('body,html').animate({
});
Working fiddle: http://jsfiddle.net/IrvinDominin/2QYgR/3/

Related

How to change when Jquery edits my CSS upon reaching an anchor point?

I've found this piece of Jquery to change CSS when it reaches an anchor point.
$(window).on("scroll", function() {
var scrollPosition = scrollY || pageYOffset;
if (scrollPosition > $("#someAnchor").position().top - $(window).height()) {
alert("run code here");
}
});
The problem is it does so when the bottom of the screen reaches the anchor point, but it needs to run the code when the top touches the anchor point. How do I do this?
Hoping this works well for you:
var ranOffsetCode = false
$(window).on("scroll", function() {
var docScrollTop = $(document).scrollTop(); // Figure out how far we scrolled.
var someAnchorTop = $('#someAnchor').offset().top - $('#someAnchor').height(); // Figure out how far down the element is on the page
if (docScrollTop >= someAnchorTop) { // If we scrolled up to or past the element, fire this
if (ranOffsetCode === false) { // This makes sure we only run the function once and not every scroll
ranOffsetCode = true;
console.log('run code here'); // Functional code to execute after we scrolled down this far.
}
}
else {
ranOffsetCode = false;
}
});
Demo
Simply remove - $(window).height()
$(window).on("scroll", function() { var scrollPosition = scrollY || pageYOffset;
if (scrollPosition > $("#someAnchor").position().top) { alert("run code here"); } });
Not really meant to be an answer, but it might help:
var spam = false;
$(window).on("scroll", function() {
var scrollPosition = scrollY || pageYOffset;
$('#pos').html( 'y: '+scrollY+', a: '+$("#someAnchor").position().top + ', p: '+scrollPosition );
if (!spam && (scrollPosition > $("#someAnchor").position().top)) {
alert('hit it!');
spam = true;
}
});
Some html:
<div style="position:fixed; top:0; left:85%; width:15%; height:20px">
<span id="pos" style="font-family:Courier; font-size:0.5em; white-space:pre"></span>
</div>

Floating JQuery menu issues on slower connection

I'm trying to create a floating menu (#quickmenu in left hand sidebar of bottom link) that stops at #weather whilst also re-calculating the bottom = $(\'#weather\').offset().top; every 0.5 seconds...
Page to test: Bristol International Jazz & Blues Festival 2014 | Festival Archive
The recalculation is key as I use expandable content in the main body and because without recaculating on slower connections it doestn't work. I need only #weather.offset.top to be recalculated every 5 seconds, not the whole script otherwise it refreshes and flickers...
I've tried to do code it myself and it's not working, it's 99% not coded correctly but can't figure out what's going wrong? The logic seems to be correct though... if (y >= top && z <= bottom) { ....
<script type="text/javascript">
$(document).ready(function () {
top = $('#quickmenu').offset().top;
var didScroll = false;
$(window).scroll(function() {
didScroll = true;
});
setInterval(function() {
if ( didScroll ) {
didScroll = false;
bottom = $('#weather').offset().top;
y = $(this).scrollTop();
z = y + $('#quickmenu').height();
if (y >= top && z <= bottom) {
// if so, add the fixed class
$('#quickmenu').addClass('fixed');
} else if(z > bottom) {
// otherwise remove it
$('#quickmenu').removeClass('fixed').addClass('absolute');
} else {
// otherwise remove it
$('#quickmenu').removeClass('fixed');
}
}
}, 500);
});
</script>
Thanks for the input, and apologies for lack of clarity within the question. I have fixed my issue by taking another approach. I hope that this is less resource heavy?
<script type="text/javascript">
(function () {
var s = document.querySelector(\'#event-info\').style;
s.overflow = \'inherit\';
s.height = \'auto\';
})();
window.updateQuickMenuPos = function () {
var menu = document.querySelector(\'#quickmenuwrapper\');
var scroll_pos = document.body.scrollTop;
var menu_pos = menu.offsetTop + 10;
var weather = document.querySelector(\'#weather\');
var pos = (scroll_pos - menu_pos);
// min height
if (pos < 0) {
pos = 0;
}
// max height
if (menu_pos + menu.offsetHeight + pos > weather.offsetTop) {
pos = weather.offsetTop - menu.offsetHeight - menu_pos;
}
var s = menu.style;
s[\'webkitTransform\'] = s[\'mozTransform\'] = s[\'transform\'] = \'translateY(\' + pos + \'px)\';
};
jQuery(document).scroll(window.updateQuickMenuPos);
</script>

Get static value from variable (scroll function)

I have a "follow scroll" function, but I want it to turn off when it returns to a certain point. My code is as follows:
scrollSidebar: function(scroll) {
var elemPos = $('#bestvideos-2').offset().top,
scroll2 = scroll;
if(scroll2 >= elemPos) {
$('#bestvideos-2').animate({
'margin-top':(scroll - 315)+'px'
},0);
} else {
$('#bestvideos-2').css('margin-top','0');
}
}
$(window).scroll(function() {
var scrollHeight = $(window).scrollTop();
Scroll.scrollSidebar(scrollHeight);
})
The problem is - every time I get up, it goes way up, not following scroll. What I'm thinking is storing a variable elemPos somewhere and keep it static (now it's changing each time I scroll).
What can I do with this?
Pass the value to the scrollSidebar function - make sure that the var elemPos = $('#bestvideos-2').offset().top is executed on dom ready
scrollSidebar: function (elemPos, scroll) {
var scroll2 = scroll;
if (scroll2 >= elemPos) {
$('#bestvideos-2').animate({
'margin-top': (scroll - 315) + 'px'
}, 0);
} else {
$('#bestvideos-2').css('margin-top', '0');
}
}
var elemPos = $('#bestvideos-2').offset().top
$(window).scroll(function () {
var scrollHeight = $(window).scrollTop();
Scroll.scrollSidebar(elemPos, scrollHeight);
})

scroll other scrollbars with scrollbar

i have 3 divs with scrollbars.
If i scroll in div 1 i want to scroll div 2 and 3 in the opposite direction.
The distance scrolled should be half the distance of div 1.
This is what i have now (small part, rest is in jsfiddle), which works for 1 div.
$("#textBox1").scroll(function () {
console.log("scroll 1");
var offset = $("#textBox1").scrollTop() - scrollPosTBox1;
var half_offset = offset/2.0;
disable1 = true;
if(disable2 == false) {
$("#textBox2").scrollTop(scrollPosTBox2 - half_offset);
}
if(disable3 == false) {
$("#textBox3").scrollTop(scrollPosTBox3 - half_offset);
}
disable1 = false;
});
However, if i try to get the same for the other 2 divs then i can't scroll anything anymore.
This is because div 1 triggers div 2 and div 2 triggers back to div 1 for example.
I tried to fix this with the disable code but it doesn't help.
Can someone help me?
http://jsfiddle.net/XmYh5/1/
No disrespect to #EmreErkan and #Simon for their effort. Here's a no-click version of this.
var $boxes = $("#textBox1,#textBox2,#textBox3"),
active;
$boxes.scrollTop(150);
// set initial scrollTop values
updateScrollPos();
// bind mouseenter:
// 1) find which panel is active
// 2) update scrollTop values
$boxes.mouseenter(function () {
active = this.id;
updateScrollPos();
});
// bind scroll for all boxes
$boxes.scroll(function (e) {
$this = $(this);
// check to see if we are dealing with the active box
// if true then set scrolltop of other boxes relative to the active box
if(this.id == active){
var $others = $boxes.not($this),
offset = $this.scrollTop()-$this.data("scroll"),
half_offset = offset / 2;
$others.each(function(){
$this = $(this);
$this.scrollTop($this.data("scroll") - half_offset);
});
}
});
// utility function:
// assign scrollTop values element's data attributes (data-scroll)
function updateScrollPos() {
$boxes.each(function(){
$this = $(this);
$this.data("scroll",$this.scrollTop());
});
}
Fiddle
You can use a variable to determine active textbox with .mousedown() and do the trick if it's active;
var activeScroll = '';
$("#textBox1").on('mousedown focus mouseenter', function () {
activeScroll = 'scroll1';
}).scroll(function () {
if (activeScroll == 'scroll1') {
console.log("scroll 1");
var offset = $("#textBox1").scrollTop() - scrollPosTBox1;
var half_offset = offset / 2.0;
$("#textBox2").scrollTop(scrollPosTBox2 - half_offset);
$("#textBox3").scrollTop(scrollPosTBox3 - half_offset);
}
});
You can check your updated jsFiddle here.
Finally got a dynamic solution for this, was more complex than I thought but I think I got it:
http://jsfiddle.net/XmYh5/14/
var initialTop = 150,
factor = 2;
$(".textBox")
.addClass('disabled')
.scrollTop(initialTop)
.on('scroll', function () {
var $this = $(this);
if(!$this.is('.disabled')) {
this.lastOffset = this.lastOffset || initialTop;
var offset = $this.scrollTop(),
step = (offset - this.lastOffset) / factor;
$this.siblings().each( function() {
var $this = $(this),
offset = $this.scrollTop() - step;
$this.scrollTop(offset);
this.lastOffset = offset;
});
this.lastOffset = offset;
}
})
.on('mouseenter', function() {
$(this).removeClass('disabled').siblings().addClass('disabled');
});

.next() not working as intended

So,
if($(this).hasClass('active')){
$(this).removeClass('active');
$(this).prev().addClass('active');
}
works fine, it adds the class "active" to this previous div of the same kind.
if($(this).hasClass('active')){
$(this).removeClass('active');
$(this).next().addClass('active');
}
However, adds the class to the next div (as i intend for it to do) for about 0.5 of a second BUT then removes it.
Here's ALL of the jQuery (as per your comments below) - Please do not comment on my horrible code organization
$(window).load(function () {
// Initial variables
var numberSlides = 0;
var currentSlide = 1;
var ready = true;
var pageWidthR = $(document).width() - 352;
var pageWidthL = $(document).width() - 352;
// Update number of slides by number of .slide elements
$('#features-slider .slide').each(function () {
numberSlides++;
});
// Go through each slide and move it to the left of the screen
var i = 0;
$($('#features-slider .slide').get().reverse()).each(function () {
if (i == 0) {
} else {
var newWidth = i * 115;
$(this).css('left', '-' + newWidth + '%');
}
i++;
});
// Animate the first slide in
$('#features-slider .slide:last-child').addClass('active').animate({
left: 0
}, 1500);
// Remove the loading message
$('#loading').fadeOut(1000, function () {
$('#loading').remove();
// Now that we're done - we can show it
$('#features-slider').show();
});
/***** Left and Right buttons *****/
/* Right */
$('#rightbutton').click(function () {
var numberSlides = 0;
$('#features-slider .slide').each(function () {
numberSlides++;
});
var index = $('.slide.active').index() + 1;
if (!$('.slide').is(':animated') && index != 1) {
$('#features-slider .slide').each(function () {
if ($(this).hasClass('active')) {
var currentLeft = $(this).css('left');
var newLeft = parseInt(currentLeft) + 115;
} else {
var currentLeft = $(this).css('left');
var newLeft = parseInt(currentLeft) + 115;
}
$(this).animate({
left: newLeft + '%'
}, 1500);
if ($(this).hasClass('active')) {
$(this).removeClass('active');
$(this).prev().addClass('active');
}
});
}
});
/* Left */
$('#leftbutton').click(function () {
var numberSlides = 0;
$('#features-slider .slide').each(function () {
numberSlides++;
});
var index = $('.slide.active').index() + 1;
if (!$('.slide').is(':animated') && index != numberSlides) {
$('#features-slider .slide').each(function () {
if ($(this).hasClass('active')) {
var currentLeft = $(this).css('left');
var newLeft = parseInt(currentLeft) - 115;
} else {
var currentLeft = $(this).css('left');
var newLeft = parseInt(currentLeft) - 115;
}
$(this).animate({
left: newLeft + '%'
}, 1500);
if ($(this).hasClass('active')) {
$(this).next().addClass('active');
$(this).removeClass('active').not($(this).next());
}
});
}
});
});
$(document).ready(function () {
// Hide the slider and show a loading message while we do stuff and the images / DOM loads - Also disable overflow on the body so no horizontal scrollbar is shown
$('body').css('overflow-x', 'hidden');
$('#features-slider').hide();
$('#loading').html('<center> <img id="loader" src="/wp-content/themes/responsive/library/images/ajax-loader.gif" /> Loading</center>');
});
RESOLVED
New left button function :
$('#leftbutton').click(function(){
var numberSlides = 0;
$('#features-slider .slide').each(function(){
numberSlides++;
});
var index = $('.slide.active').index()+1;
if( !$('.slide').is(':animated') && index != numberSlides ){
var done = false;
$('#features-slider .slide').each(function(){
if($(this).hasClass('active')){
var currentLeft = $(this).css('left');
var newLeft = parseInt(currentLeft)-115;
} else {
var currentLeft = $(this).css('left');
var newLeft = parseInt(currentLeft)-115;
}
$(this).animate({left: newLeft+'%'}, 1500);
if($(this).hasClass('active') && done == false){
$(this).next().addClass('active');
$(this).removeClass('active');
done = true;
}
});
});
If you're iterating forward through the elements, then it should be clear what's going on - you add the "active" class to the next element, and then the next iteration takes it away.
This is just a guess however as you did not post enough code for me (or anybody else) to be sure.
edit — ok now that you've updated the question, it's clear that the guess was correct. The .each() function will iterate forward through the elements. When an element has the "active" class, and the code removes it and adds it to the next element, then on the next iteration the work is undone.
Since you are referencing this and by the behavior you're describing, you are likely iterating a loop for a list of elements. As a result, you are completing the action you want but the next iteration is removing the previous changes due to your usage of removing a class and then adding the class back.
As it stands now, your code does not illustrate how this occurence can be happening.
Update:
As suspected, you seem to be looping as signified by: each(function(){. While iterating through your objects the class is being pushed forward and is not acting as desired. You are stating add the class to the next element, but remove it from the current element, and this behavior continues through your iteration.
On a side note, update your code to call removeClass() on the current object first, before adding it to the next object:
if ($(this).hasClass('active')) {
$(this).removeClass('active').next().addClass('active');
}

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