Develop Reference

Finding where element meets top of scrollable div

I have a scrollable div container fits multiple "pages" (or div's) inside of it's container.
My goal is to, at any given moment, figure out where inside my red container does it reach the top of my scrollable container. So it can be a constant on scroll event, or a button that triggers this task.
So for example. If I have a absolute div element inside one of my red boxes at top:50px. And if I scroll to where that div element reaches the top of my scrollable container. The trigger should say that I am at 50px of my red container.
I'm having a hard time grasping how to accomplish this but I've tried things like:
$("#pageContent").scroll(function(e) {
console.log($(this).scrollTop());
});
But it doesn't take into account the separate pages and I don't believe it it completely accurate depending on the scale. Any guidance or help would be greatly appreciated.
Here is my code and a jsfiddle to better support my question.
Note: If necessary, I use scrollspy in my project so I could target which red container needs to be checked.
HTML
<div id="pageContent" class="slide" style="background-color: rgb(241, 242, 247); height: 465px;">
<div id="formBox" style="height: 9248.627450980393px;">
<div class="trimSpace" style="width: 1408px; height: 9248.627450980393px;">
<div id="formScale" style="width: 816px; -webkit-transform: scale(1.7254901960784315); display: block;">
<form action="#" id="XaoQjmc0L51z_form" autocomplete="off">
<div class="formContainer" style="width:816px;height:1056px" id="xzOwqphM4GGR_1">
<div class="formContent">
<div class="formBackground">
<div style="position:absolute;top:50px;left:100px;width:450px;height:25px;background-color:#fff;color:#000;">When this reaches the top, the "trigger" should say 50px"</div>
</div>
</div>
</div>
<div class="formContainer" style="width:816px;height:1056px" id="xzOwqphM4GGR_2">
<div class="formContent">
<div class="formBackground"><div style="position:absolute;top:50px;left:100px;width:450px;height:25px;background-color:#fff;color:#000;">This should still say 50px</div></div>
</div>
</div>
</form>
</div>
</div>
</div>
</div>
CSS
#pageContent {
position:relative;
padding-bottom:20px;
background-color:#fff;
z-index:2;
overflow:auto;
-webkit-overflow-scrolling: touch;
-webkit-transform: translate(0, 0);
-moz-transform: translate(0, 0);
-ms-transform: translate(0, 0);
transform: translate(0, 0);
}
#formBox {
display: block;
position: relative;
height: 100%;
padding: 15px;
}
.trimSpace {
display: block;
position: relative;
margin: 0 auto;
padding: 0;
height: 100%;
overflow: hidden;
}
#formScale::after {
display: block;
content:'';
padding-bottom:5px;
}
#formScale {
position:relative;
width:816px;
margin:0;
-webkit-transform-origin: 0 0;
-moz-transform-origin: 0 0;
transform-origin: 0 0;
-ms-transform-origin: 0 0;
}
.formContainer {
position:relative;
margin : 0 auto 15px auto;
padding:0;
}
.formContent {
position:absolute;
width:100%;
height:100%;
}
.formBackground {
width:100%;
height:100%;
background-color:red;
}
JS
var PAGEWIDTH = 816;
$(window).resize(function (e) {
zoomProject();
resize();
});
function resize() {
$("#pageContent").css('height', window.innerHeight - 45 + 'px');
}
function zoomProject() {
var maxWidth = $("#formBox").width(),
percent = maxWidth / PAGEWIDTH;
$("#formScale").css({
'transform': 'scale(' + percent + ')',
'-moz-transform': 'scale(' + percent + ')',
'-webkit-transform': 'scale(' + percent + ')',
'-ms-transform': 'scale(' + percent + ')'
});
$(".trimSpace").css('width', (PAGEWIDTH * percent) + 'px');
$("#formBox, .trimSpace").css('height', ($("#formScale").height() * percent) + 'px');
}
zoomProject();
resize();
EDIT:
I don't think I am conveying a good job at relaying what I want to accomplish.
At the moment there are two .formContainer's. When I scroll #pageContainer, the .formContainer divs move up through #pageContainer.
So what I want to accomplish is, when a user clicks the "ME" button or #click (as shown in the fiddle below), I'd like to know where in that particular .formContainer, is it touching the top of #pageContainer.
I do use scroll spy in my real world application so I know which .formContainer is closest to the top. So if you just want to target one .formContainer, that is fine.
I used these white div elements as an example. If I am scrolling #pageContainer, and that white div element is at the top of screen as I am scrolling and I click on "ME", the on click trigger should alert to me that .formContainer is touching the top of #pageContainer at 50px from the top. If, the the red container is just touching the top of #pageContainer, it should say it is 0px from the top.
I hope that helps clear up some misconception.
Here is an updated jsfiddle that shows the kind of action that I want to happen.

I am giving this a stab because I find these things interesting. It might just be a starting point since I have a headache today and am not thinking straight. I'd be willing to bet it can be cleaned up and simplified some.
I also might be over-complicating the approach I took, getting the first visible form, and the positioning. I didn't use the getBoundingClientRect function either.
Instead, I approached it trying to account for padding and margin, using a loop through parent objects up to the pageContent to get the offset relative to that element. Because the form is nested a couple levels deep inside the pageContent element you can't use position(). You also can't use offset() since that changes with scroll. The loop approach allowed me to factor the top margin/padding in. I haven't looked at the other solutions proposed fully so there might be a shorter way to accomplish this.
Keeping in mind that the scale will affect the ACTUAL location of the child elements, you have to divide by your scale percentage when getting the actual location. To do that I moved the scalePercentage to a global var so it was usable by the zoom function and the click.
Here's the core of what I did. The actual fiddle has more logging and junk:
var visForm = getVisibleForm();
var formTop = visForm.position().top;
var parents = visForm.parentsUntil('#pageContent');
var truOffset = 0;
parents.each(function() {
truOffset -= $(this).position().top;
});
// actual location of form relative to pageContent visible pane
var formLoc = truOffset - formTop;
var scaledLoc = formLoc / scalePercent;
Updated Fiddle (forgot to account for scale in get func): http://jsfiddle.net/e6vpq9c8/5/

If I understand your question correctly, what you want is to catch when certain descendant elements reach the top of the outer container, and then determine the position of the visible "page" (div with class formContainer) relative to the top.
If so, the first task is to mark the specific elements that could trigger this:
<div class='triggerElement' style="position:absolute;top:50px;left:100px;width:450px;height:25px;background-color:#fff;color:#000;">When this reaches the top, the "trigger" should say 50px"</div>
Then the code:
// arbitrary horizontal offset - customize for where your trigger elements are placed horizontally
var X_OFFSET = 100;
// determine once, at page load, where outer container is on the page
var outerContainerRect;
$(document).ready(function() {
outerContainerRect = $("#pageContent").get(0).getBoundingClientRect();
});
// when outer container is scrolled
$("#pageContent").scroll(function(e) {
// determine which element is at the top
var topElement = $(document.elementFromPoint(outerContainerRect.left+X_OFFSET, outerContainerRect.top));
/*
// if a trigger element
if (topElement.hasClass("triggerElement")) {
// get trigger element's position relative to page
console.log(topElement.position().top);
}
*/
var page = topElement.closest(".formContainer");
if (page.length > 0) {
console.log(-page.get(0).getBoundingClientRect().top);
}
});
EDIT: Changed code to check formContainer elements rather than descendant elements, as per your comment.
http://jsfiddle.net/j6ybgf58/23/
EDIT #2: A simpler approach, given that you know which formContainer to target:
$("#pageContent").scroll(function(e) {
console.log($(this).scrollTop() - $("#xzOwqphM4GGR_1").position().top);
});
http://jsfiddle.net/rL4Ly3yy/5/
However, it still gives different results based on the size of the window. This seems unavoidable - the zoomProject and resize functions are explicitly resizing the content, so you would have to apply the inverse transforms to the number you get from this code if you want it in the original coordinate system.

I do not fully understand what it is that you are needing, but if i am correct this should do the trick
$("#pageContent").scroll(function(e) {
// If more then 50 pixels from the top has been scrolled
// * if you want it to only happen at 50px, just execute this once by removing the scroll listener on pageContent
if((this.scrollHeight - this.scrollTop) < (this.scrollHeight - 50)) {
alert('it is');
}
});
ScrollHeight is the full height of the object including scrollable pixels.
ScrollTop is the amount of pixels scrolled from the top.

You can use waypoints to detect the position of divs based on where you're scrolling.
Here is a link to their official website's example: http://imakewebthings.com/waypoints/shortcuts/inview/

Span banner image across width of browser window

So Far:
The image is shown on the browser, but it is not resized.
<html>
<img id="banner" src="c:/Users/Name/Downloads/picture.jpg" alt="banner" />
<Script>
var X = screen.width;
var Y = screen.height;
banner = document.getElementById('banner');
banner.style.width = X + 'px';
banner.style.height = (Y/5) + 'px';
</Script>
</html>
Other Attempts:
Show the image using purely javascript
Width and height variables accessed through javascript
First, try with no size specs
Image is not shown when I use:
document.write("<img src='c:/Users/Name/Downloads/picture.jpg' />")
Future Thoughts:
My next attempt will be trying to pass the javascript width and height variables to the html since it seems that the html image always shows and given the right size specifications, then that would be exactly what I want. I will post that here if I find a successful method.

markup and CSS like this should do trick for you.
<div class="banner"></div>
div
{
background:url(https://www.google.com/images/srpr/logo11w.png) no-repeat left top;
width:100%;
height:200px;
background-size:cover;
}
Or even better you can try this CSS instead of above
div
{
position:fixed;
left:0px;
right:0px;
top:0;
height:250px;
background:url(https://www.google.com/images/srpr/logo11w.png) no-repeat center center;
}

Image Slider with "Responsive Width", "Fixed Height", "Center Aligned" and "Auto Rotate"

I need a full width (responsive) slider with fixed height and centered image ( the min width is 960px and people with a wider screens will see the rest of the image (the extra on the left and right)) and it needs to auto-rotate.
Now I got the html/css worked out, but my javascript is rubbish so i have no idea how to let the images slide. I've checked out a lot of Questions here but nothing seems to work. My image dimensions are 2300x350.
CSS:
body {
margin: 0 auto;
}
#slider_container {
width:100%;
height:350px;
overflow:hidden;
position: relative;
z-index: 1;
}
.image {
position:relative;
float:left;
height: 350px;
width: 100%;
overflow: hidden;
}
.image img {
position:absolute;
left:50%;
top:50%;
margin-left:-1150px;
margin-top:-175px;
}
HTML:
<div id="slider_container">
<div class="image">
<img src="images/header.jpg" />
</div>
<div class="image">
<img src="images/header2.jpg"/>
</div>
<div class="image">
<img src="images/header3.jpg" />
</div>
</div>
With this code the pictures come out nice in the middle on every screen but
how do I let it slide and autorotate? I guess the first image just needs to be replaced by the second so a z-index change? or + or - the width of one picture?

You need to only style the img tag if using flexslider. Try the fiddle link below. I have included four files for this.
jQuery 1.9.1
flexslider.css
jquery.flexslider-min.js
bg_direction_nav.png
jsfiddle

Please check this... http://www.jqueryscript.net/demo/Responsive-jQuery-Full-Width-Image-Slider-Plugin-responsiveSlides/ it is full width and fixed height slider and auto rotate. Here you have options to styling according to your needs
$(function(){
var p=$('#content').responsiveSlides({
height:450, // slides conteiner height
background:'#fff', // background color and color of overlayer to fadeout on init
autoStart:true, // boolean autostart
startDelay:0, // start whit delay
effectInterval:5000, // time to swap photo
effectTransition:1000, // time effect
pagination:[
{
active:true, // activate pagination
inner:true, // pagination inside or aouside slides conteiner
position:'B_R', /*
pagination align:
T_L = top left
T_C = top center
T_R = top right
B_L = bottom left
B_C = bottom center
B_R = bottom right
*/
margin:10, // pagination margin
dotStyle:'', // dot pagination class style
dotStyleHover:'', // dot pagination class hover style
dotStyleDisable:'' // dot pagination class disable style
}
]
});
});
For more modification please see jquery.responsiveSlides.js

Fully expand this CSS inline-block div scan-line

I want this scan line effect to work properly. To reveal the text from left to right. As if the cathode-ray is burning it into the phosphors on the screen.
The idea is to slide across black rows, that have a transparent tip. Here is a 80% working demo.
The rightmost black .mask div in every row will not expand. It must.
I have tried to keep the right-most .mask div with a black background as inline-block and make it full width. I somewhat understand why the request does not work (width:100% pushes the other inline-blocks onto the next line, as is only proper), but there must be a way to get this full right hand side without hacking the widths in javascript.
.row {
font-family:'Courier New',Courier,monospace;
font-size:16px;
display:block;
height:auto;
width:100%;
min-width:20%;
position:relative;
margin-right:0px;
}
.mask {
display:inline-block;
width:auto; /* 100% does not work */
background:black;
white-space:pre;
}

this won't work on jsbin becuase it uses absolute positioning (unless you view the full screen demo).. but I provided it anyways for you to copy/paste it into your own browser http://jsbin.com/uteyik/12/.. below are the change highlights:
css:
.row {
..
position:absolute; /* changed to absolute */
}
.mask {
..
width:100%; /* changed to 100% */
position:absolute; /*changed to absolute */
}
and javascript:
jQuery(document).ready(function() {
function fill_box(rows) {
var rowHeight = getSampleRowHeight();
var thisRowHeight = 0;
for(var i = 0; i < rows; i += 1) {
$('.box').append('<div class="row" style="top: '+thisRowHeight+'"><div class="scan_cursor i1"> </div><div class="scan_cursor i2"> </div><div class="scan_cursor i3"> </div><div class="mask"> </div></div>');
thisRowHeight +=rowHeight;
}
}
fill_box(30);
function tag_animate(el) {
// animate the mask
el.animate( {
'margin-left' : '100%'
},
{
complete : function () {
tag_animate(el.parent().next().find('.mask'));
}
}
);
// animate the stripes
el.siblings().animate( {
'margin-left': '100%'
},
{
complete : function () {
el.siblings().hide();
}
}
);
}
tag_animate($('.box').find('.row').eq(0).find('.mask'));
function getSampleRowHeight() {
// get sample row height, append to dom to calculate
$('.box').append('<div class="row" style="display: hidden"> <div class="scan_cursor i1"> </div></div>');
var rowHeight = $('.row').height();
$('.box').find('.row').remove();
return rowHeight;
}
});
explanation: I first create a dummy row and calculate it's height. I then create rows that have position: absolute and position it from the top using the dummy row height x row number. the idea is that I wanted to make everything with absolute positioning so that the mask doesn't push the stripes below when it's 100%, also the row has to be absolute because as I make it's contents disappear, I don't want the rows below to jump up.
bonus: see it work the opposite way (ie the text disappearing): http://jsbin.com/uteyik/9 this was my initial (and incorrect) answer

Slide gallery with image tooltips, images breaking out of unlimited width block

I'm trying to develop a slide gallery with image tooltips according to this design:
What I need to develop is a slider controlled by two buttons, each time a button is pressed the slider's content must move a width of the slider or the width of the content left on that side, whichever is smaller. Upon mouse entering an image inside the slider the full-size version must be displayed as a tooltip.
Here's a fiddle of my solution so far, the problem I'm having is that images that don't fully fit into view plus the hidden area to the left get moved to a new line. You can see the problem by clicking the
"Show content size" button, the width of the content element will be equal to the width of the container element + content element's margin-left.
Bonus points if you can suggest an algorithm for moving the content to the right, I've got left figured out to a T (or so I think, anyway), but right is going to take a little more work (it doesn't check whether the end of the content has been reached). Update: It seems I can't implement proper movement to the right until the other issue is resolved, here's the algorithm I came up with, I can't measure "left to display" if I can't measure the actual width of the content element.

I created something you might like:
gallery demo
The gallery does not scroll the full gallery width by default (you can change that) cause some initially cut-off images at the right side, after a 'full' slide would result cut-off again, just on the other side of our gallery. You have for that cause the beKind variable. Adjust it as you like.
It hides the buttons if there's not enough content to make the gallery usable.
The gallery calculates the remaining space to scroll.
Once the slider end reached - the left/right buttons make the gallery jump to the beginning/end, so that are always usable. (Seems kinda weird to have a button... but that does nothing right? ;) )
The Tooltip has a hover-intent built in, to not piss off our users if they unintentionally hovered our gallery: (the tooltip fades in if the hover is registered for more that 120ms. Fair timing. I like it.)
As pointed out in your comment now the tooltip will not go off the screen.
jQ:
// Slide Kind Gallery - by roXon // non plugin v. // CC 2012.
$(window).load(function(){
var galW = $('#gallery').outerWidth(true),
beKind = 120, // px substracted to the full animation to allow some images to be fully visible - if initially partly visible.
sumW = 0;
$('#slider img').each(function(){
sumW += $(this).outerWidth(true);
});
$('#slider').width(sumW);
if(sumW <= galW){ $('.gal_btn').remove(); }
function anim(dir){
var sliderPos = Math.abs($('#slider').position().left),
rem = dir ==='-=' ? rem = sumW-(sliderPos+galW) : rem = sliderPos,
movePx = rem<=galW ? movePx = rem : movePx = galW-beKind;
if( movePx <= 10){
movePx = dir==='-=' ? movePx=rem : movePx = galW-sumW;
dir = '';
}
$('#slider').stop(1).animate({left: dir+''+movePx },1000);
}
$('.gal_btn').on('click', function(){
var doit = $(this).hasClass('gal_left') ? anim('+=') : anim('-=');
});
});
And the tooltip script:
// Addon // Tooltip script
var $tt = $('#tooltip');
var ttW2 = $tt.outerWidth(true)/2;
var winW = 0;
function getWW(){ winW = $(window).width(); }
getWW();
$(window).on('resize', getWW);
$('#slider img').on('mousemove',function(e){
var m = {x: e.pageX, y: e.pageY};
if( m.x <= ttW2 ){
m.x = ttW2;
}else if( m.x >= (winW-ttW2) ){
m.x = winW-ttW2;
}
$tt.css({left: m.x-ttW2, top: m.y+10});
}).hover(function(){
$clon = $(this).clone();
var t = setTimeout(function() {
$tt.empty().append( $clon ).stop().fadeTo(300,1);
},120);
$(this).data('timeout', t);
},function(){
$tt.stop().fadeTo(300,0,function(){
$(this).hide();
});
clearTimeout($(this).data('timeout'));
});
HTML
(Place the #tooltip div after the body tag)
<div id="tooltip"></div>
<div id="gallery_container">
<div id="gallery">
<div id="slider">
<img src="" alt="" />
<img src="" alt="" />
</div>
</div>
<div class="gal_left gal_btn">◀</div>
<div class="gal_right gal_btn">▶</div>
</div>
CSS:
/*GALLERY*/
#gallery_container{
position:relative;
margin:0 auto;
width:600px;
padding:0 30px; /*for the buttons */
background:#eee;
border-radius:5px;
box-shadow: 0 2px 3px #888;
}
#gallery{
position:relative;
height:100px;
width:600px;
overflow:hidden;
}
#slider{
position:absolute;
left:0px;
height:100px;
}
#slider img{
height:100.999%; /* fixes some MOZ image resize inconsistencies */
float:left;
cursor:pointer;
border-right:3px solid transparent; /* instead of margin that could leat to some wrong widths calculations. */
}
.gal_btn{
position:absolute;
top:0px;
width:30px; /*the container padding */
height:40px;
padding:30px 0;
text-align:center;
font-size:30px;
cursor:pointer;
}
.gal_left{left:0px;}
.gal_right{right:0px;}
/* end GALLERY */
/* TOOLTIP ADDON */
#tooltip{
position:absolute;
z-index:100;
width:300px;
padding:10px;
background:#fff;
background: rgba(255,255,255,0.3);
box-shadow:0px 3px 6px -2px #111;
display:none;
}
#tooltip *{
width:100%;
vertical-align:middle;
}
/* end TOOLTIP ADDON */
Hope you'll like it, and you learned some useful UI design tricks.
By the way, if you want to populate your ALT attributes (Search engines like it!) you can also grab that text and make it appear inside the tooltip like here!:
demo with text inside the tooltip
Happy coding.

I don't know if I understand correctly your problem. If you set a width wide enough to .scroll-content div, images wouldn't go to the "next line". So a solution would be to set a width with css. If not, you could use jquery to determine the total width of all the images and give it to the .scroll-content div. Calculate total width of Children with jQuery