JQuery Resize - Bring to Front - javascript

I've made several overlapping objects draggable and resizable via the JQuery Draggable and Resizable plugins. When dragging an object, it's instantly brought up to the frontmost position thanks to the stack option. The Resizable plugin doesn't have this option so when an element in the background is being resized but not dragged, it stays in the back.
How do I make an object being resized jump to the front just like it happens when it's being dragged?
Thanks

You can implement this yourself by using the start event of the resizable widget.
In that event you just loop through your draggable/resizable elements to find the highest zIndex, then set your currently resizing element higher in the stack.
For example (heavily commented for clarity).
// Common class of our draggable/resizable elements
const targetClass = ".foo";
$(targetClass)
.resizable({
start: (event, ui) => {
// current resizing element
const element = $(ui.element[0]);
let topZIndex = 0;
// loop over all our elements
$(targetClass).each((i, obj) => {
// get the current zIndex as an int, using the unary operator
// and accounting for NaN values like 'auto'
const currentZIndex = +$(obj).css("zIndex") || 0;
// if current zIndex is higher, update the topZIndex
currentZIndex > topZIndex && (topZIndex = currentZIndex);
});
// set the resizing elements zIndex above the highest
element.css("zIndex", topZIndex + 1);
}
})
.draggable({
stack: targetClass
});
.foo {
width: 100px;
height: 100px;
padding: 0.5em;
position: absolute !important;
}
.foo h3 {
text-align: center;
margin: 0;
}
<script src="https://code.jquery.com/jquery-3.6.0.js"></script>
<script src="https://code.jquery.com/ui/1.13.2/jquery-ui.js"></script>
<link rel="stylesheet" href="//code.jquery.com/ui/1.13.2/themes/base/jquery-ui.css">
<div id="container">
<div class="foo ui-widget-content">
<h3 class="ui-widget-header">test 1</h3>
</div>
<div class="foo ui-widget-content">
<h3 class="ui-widget-header">test 2</h3>
</div>
<div class="foo ui-widget-content">
<h3 class="ui-widget-header">test 3</h3>
</div>
</div>

Related

JavaScript: Detect if DOM element overlaping, inside or ouside with DOM element?

I'm making a small game in JavaScript. I've created a small example js fiddle demo link. There are three situations as listed bellow:
A: Outside of target object.
B: Overlaping with target object's border.
C: Inside of target object.
According to Have object detect if completely inside other object JavaScript, I've known how to detect if the object inside of target (Situation C). How about situation A and B?
<div class="main">
<div class="target"></div>
<div class="obj">A</div>
<div style="top:15%; left:50%;" class="obj">B</div>
<div style="top:25%; left:35%;" class="obj">C</div>
</div>
One way to do this would be to use Element#getBoundingClientRect() to obtain the absolute coordinates of the DOM elements being classified for overlap, containment, etc.
This function returns to top, right, bottom and left coordiates of the corresponding DOM element which you can use to determine containment of an element with respect to a container.
You could implement a function like findContainment() shown below, where the containment of element is classified against a container element:
function findContainment(element, container) {
/*
Obtain the bounding rectangle for each element
*/
const brE = element.getBoundingClientRect()
const brC = container.getBoundingClientRect()
/*
If the boundaries of container pass through the boundaries of
element then classifiy this as an overlap
*/
if (
/* Does container left or right edge pass through element? */
(brE.left < brC.left && brE.right > brC.left) ||
(brE.left < brC.right && brE.right > brC.right) ||
/* Does container top or bottom edge pass through element? */
(brE.top < brC.top && brE.bottom > brC.top) ||
(brE.top < brC.bottom && brE.bottom > brC.bottom)) {
return "overlap";
}
/*
If boundaries of element fully contained inside bounday of
container, classify this as containment of element in container
*/
if (
brE.left >= brC.left &&
brE.top >= brC.top &&
brE.bottom <= brC.bottom &&
brE.right <= brC.right
) {
return "contained"
}
/*
Otherwise, the element is fully outside the container
*/
return "outside"
}
const main = document.querySelector(".main")
console.log("A", findContainment(document.querySelector(".a"), main))
console.log("B", findContainment(document.querySelector(".b"), main))
console.log("C", findContainment(document.querySelector(".c"), main))
console.log("D", findContainment(document.querySelector(".d"), main))
console.log("E", findContainment(document.querySelector(".e"), main))
.main {
width: 50%;
height: 200px;
border: 5px solid #000;
position: relative;
}
.obj {
width: 40px;
height: 40px;
border: 1px solid blue;
position: absolute;
}
<div class="main">
<div style="top:105%; left:25%;" class="obj a">A</div>
<div style="top:15%; left:-5%;" class="obj b">B</div>
<div style="top:20%; left:40%;" class="obj c">C</div>
<div style="top:20%; left:110%;" class="obj d">D</div>
<div style="top:90%; left:95%;" class="obj e">E</div>
</div>
Here's a working fiddle as well - hope that helps!

Recalculate width of dragged element with jQuery UI draggable

I need to dynamically change the width of a <div> if it is dragged out of its parent element so its right edge stays "glued" to the parent's right edge and the contents of a <div> wrap inside the new width. After days of googling and reading posts here I've managed to resize the <div> once when it touches the parent. I tried mouseup/mousedown to restart it but it doesn't work.
The end result should work both ways (return to its original size when dragged back into the parent), something like resizing the <div> from the left edge while it's floated to the right. But for now, I at least want it to resize dynamically as I'm dragging it "out of" the parent.
I'm sure I've seen this somewhere and I refuse to believe it's impossible.
let item = $( '#item' );
let draggableRight;
let parentWidth = $('#parent').outerWidth();
function resizeMe() {
draggableRight = item.position().left + item.width();
if (draggableRight > parentWidth) {
item.width(item.width() - 50);
}
}
item.draggable({
scroll: false,
containment: 'parent',
drag: function (event, ui) {
resizeMe();
}
});
#parent {
height: 100vh;
}
#item {
position: absolute;
cursor: move;
}
<div id="parent">
<div id="item">
<span>Some random text</span>
<p>I want this to continue wrapping/shrinking as I'm dragging to the right.</p>
</div>
</div>
<script src="https://code.jquery.com/jquery-3.3.1.min.js"></script>
<script src="https://code.jquery.com/ui/1.12.1/jquery-ui.min.js"></script>

Run Jquery only when an element is in the viewport

I'm trying to perform the Jquery function below when the element becomes visible in the viewport rather than on the page load. What would I need to change to allow that to happen? I'm using an external JS file to perform the Jquery, so keep that in mind.
Here's a piece of the HTML that is associated with the Jquery function -
<div class="skillbar clearfix " data-percent="70%">
<div class="skillbar-title" style="background: #FF704D;">
<span>Illustrator</span></div>
<div class="skillbar-bar" style="background: #FF704D;"></div>
<div class="skill-bar-percent">70%</div>
</div>
jQuery(document).ready(function(){
jQuery('.skillbar').each(function(){
jQuery(this).find('.skillbar-bar').animate({
width:jQuery(this).attr('data-percent')
},4000);
});
});
I once came across such problem and what I used is waypoints small library.
all you need is to include this library and do:
var waypoint = new Waypoint({
element: document.getElementById('waypoint'),
handler: function(direction) {
console.log('Element is in viewport');
}
})
Using CSS3 transitions instead of jQuery animations might be more performant and simpler. a cheap and nasty way of pushing it out of screen to demonstarate the effect.
There's a couple of things you'll need to do - firstly if you only want the animation to trigger when it's in the viewport then you'll need to check if anything is in the viewport on scroll. Then only update the bars width when it comes into view. If you want the effect to repeat every time it comes into viewport you'll need to set .skillbar-bar's width back to 0 if it's out of the viewport (just add an else statement to the viewport checking if)
I've added a 1000px margin-top and 400px margin-bottom in my example to .skillbar as a cheap and nasty way of demonstrating the effect
(function($){
$(document).ready(function(){
var $els = $('.skillbar'); // Note this must be moved to within event handler if dynamically adding elements - I've placed it for performance reasons
var $window = $(window);
$window.on('scroll', function(){
$els.each(function(){ // Iterate over all skillbars
var $this = $(this);
if($window.scrollTop() > $this.offset().top - $window.height()){ // Check if it's in viewport
$this.find('.skillbar-bar').css({'width' : $this.attr('data-percent')}); // Update the view with percentage
}
});
});
});
}(jQuery));
.skillbar{
margin-top: 1000px;
margin-bottom: 400px;
position: relative
}
.skillbar-bar{
transition: width 4s;
position: absolute;
height: 20px;
}
.skill-bar-percent{
position: absolute;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
Scroll down 1000px :)
<div class="skillbar clearfix " data-percent="70%">
<div class="skillbar-title">
<span>Illustrator</span></div>
<div class="skillbar-bar" style="background: #FF704D; width: 20%"></div>
<div class="skill-bar-percent">70%</div>
</div>
This might work for you.
var el = $('.yourElement'),
offset = el.offset(),
scrollTop = $(window).scrollTop();
//Check for scroll position
if ((scrollTop > offset.top)) {
// Code..
}

JQuery UI - How to apply containment to selector that matches multiple divs?

Example:
<div>
<div class='drop'>
<div class='drag'></div>
</div>
<div class='drop'>
</div>
<div class='drop'>
</div>
<div class='drop'>
</div>
<div>
</div>
</div>
$('div.drag').draggable({ containment: 'div.drop' });
Normally, if there is only 1 "div.drop" element, it works as intended. If there are more than 1(like in the example above), I thought that it would be dragged/dropped in any of the "div.drop" divs. As it turns out, it is only draggable/droppable to the first element matched by the "div.drop" selector.
Is there a workaround for this(that is, make it contained/droppable/draggable only in the "div.drop" divs)?
EDIT: I guess you are right guys. After some introspection, I realized that I didn't go for your suggested solutions since there are padding between the divs and I don't want the the "div.drag" divs to be dropped on the padded area.
It don't works like that !!
The containment is to constraint bound of dragging.
You want drag and drop.
Then you have to configure drag for div.grag:
$('div.drag').draggable();
And configure drop for div.drop:
$('div.drop').droppable();
You can add containment for your drag element with your first div level:
<div id='dragZone'>
<div class='drop'>
<div class='drag'></div>
</div>
<div class='drop'>
</div>
</div>
$('div.drag').draggable({ containment: '#dragZone'});
containment restricts the movement of a draggable within the bounds of the given element(s). You could set containment to the parent of the div.drops.
You should make the div.drops droppable, append the draggable on drop, and use the revert: 'invalid' option so that the draggable reverts if it's not dropped on a droppable
$('div.drop').droppable({drop: function(e, ui) {
ui.draggable.appendTo(this);
}});
$('div.drag').draggable({
helper: 'clone',
revert: 'invalid'
});
As the guys have pointed out the containment selector does not work like that as it Constrains dragging to within the bounds of the specified element or region.
You could try something like below:
JQuery References:
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.5.0/jquery.min.js"></script>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.9/jquery-ui.min.js"></script>
HTML:
<div id="dragContainer">
<div class='drop'>
<div class='drag'>drag</div>
</div>
<div class='drop'>drop
</div>
<div class='drop'>drop
</div>
<div class='drop'>drop
</div>
<div class='nodrop'>
</div>
</div>
JQuery:
<script type="text/javascript">
$('div.drag').draggable({ containment: '#dragContainer', revert: "invalid" });
$('div.drop').droppable( {
drop: handleDropEvent
} );
function handleDropEvent( event, ui ) {
var draggable = ui.draggable;
alert( 'Ok to drop here onto me!' );
}
</script>
Do try my code
<style>
.container {
border: 2px solid #000;
}
.container img {
width: 45px;
height: 45px;
}
.draggable {
width: 40px;
height: 40px;
background: #F90;
border-radius: 10px;
margin: 0 0 0 0;
float: top;
}
.draggable.is-pointer-down {
background: #09F;
z-index: 2; /* above other draggies */
}
.draggable.is-dragging { opacity: 0.7; }
</style>
<script>
$(document).ready( function() {
var $draggables = $('.draggable').draggabilly({
// contain to parent element
    **containment: "#box"**
});
});
</script>
Hello. I think this might help you :)
<div class="container" id="box">
and my images are inside this div.

How to scroll to an element inside a div?

I have a scrolled div and I want to have an event when I click on it, it will force this div to scroll to view an element inside.
I wrote its JavasSript like this:
document.getElementById(chr).scrollIntoView(true);
but this scrolls all the page while scrolling the div itself.
How to fix that?
I want to say it like this:
MyContainerDiv.getElementById(chr).scrollIntoView(true);
You need to get the top offset of the element you'd like to scroll into view, relative to its parent (the scrolling div container):
var myElement = document.getElementById('element_within_div');
var topPos = myElement.offsetTop;
The variable topPos is now set to the distance between the top of the scrolling div and the element you wish to have visible (in pixels).
Now we tell the div to scroll to that position using scrollTop:
document.getElementById('scrolling_div').scrollTop = topPos;
If you're using the prototype JS framework, you'd do the same thing like this:
var posArray = $('element_within_div').positionedOffset();
$('scrolling_div').scrollTop = posArray[1];
Again, this will scroll the div so that the element you wish to see is exactly at the top (or if that's not possible, scrolled as far down as it can so it's visible).
You would have to find the position of the element in the DIV you want to scroll to, and set the scrollTop property.
divElem.scrollTop = 0;
Update:
Sample code to move up or down
function move_up() {
document.getElementById('divElem').scrollTop += 10;
}
function move_down() {
document.getElementById('divElem').scrollTop -= 10;
}
Method 1 - Smooth scrolling to an element inside an element
var box = document.querySelector('.box'),
targetElm = document.querySelector('.boxChild'); // <-- Scroll to here within ".box"
document.querySelector('button').addEventListener('click', function(){
scrollToElm( box, targetElm , 600 );
});
/////////////
function scrollToElm(container, elm, duration){
var pos = getRelativePos(elm);
scrollTo( container, pos.top , 2); // duration in seconds
}
function getRelativePos(elm){
var pPos = elm.parentNode.getBoundingClientRect(), // parent pos
cPos = elm.getBoundingClientRect(), // target pos
pos = {};
pos.top = cPos.top - pPos.top + elm.parentNode.scrollTop,
pos.right = cPos.right - pPos.right,
pos.bottom = cPos.bottom - pPos.bottom,
pos.left = cPos.left - pPos.left;
return pos;
}
function scrollTo(element, to, duration, onDone) {
var start = element.scrollTop,
change = to - start,
startTime = performance.now(),
val, now, elapsed, t;
function animateScroll(){
now = performance.now();
elapsed = (now - startTime)/1000;
t = (elapsed/duration);
element.scrollTop = start + change * easeInOutQuad(t);
if( t < 1 )
window.requestAnimationFrame(animateScroll);
else
onDone && onDone();
};
animateScroll();
}
function easeInOutQuad(t){ return t<.5 ? 2*t*t : -1+(4-2*t)*t };
.box{ width:80%; border:2px dashed; height:180px; overflow:auto; }
.boxChild{
margin:600px 0 300px;
width: 40px;
height:40px;
background:green;
}
<button>Scroll to element</button>
<div class='box'>
<div class='boxChild'></div>
</div>
Method 2 - Using Element.scrollIntoView:
Note that browser support isn't great for this one
var targetElm = document.querySelector('.boxChild'), // reference to scroll target
button = document.querySelector('button'); // button that triggers the scroll
// bind "click" event to a button
button.addEventListener('click', function(){
targetElm.scrollIntoView()
})
.box {
width: 80%;
border: 2px dashed;
height: 180px;
overflow: auto;
scroll-behavior: smooth; /* <-- for smooth scroll */
}
.boxChild {
margin: 600px 0 300px;
width: 40px;
height: 40px;
background: green;
}
<button>Scroll to element</button>
<div class='box'>
<div class='boxChild'></div>
</div>
Method 3 - Using CSS scroll-behavior:
.box {
width: 80%;
border: 2px dashed;
height: 180px;
overflow-y: scroll;
scroll-behavior: smooth; /* <--- */
}
#boxChild {
margin: 600px 0 300px;
width: 40px;
height: 40px;
background: green;
}
<a href='#boxChild'>Scroll to element</a>
<div class='box'>
<div id='boxChild'></div>
</div>
Native JS, Cross Browser, Smooth Scroll (Update 2020)
Setting ScrollTop does give the desired result but the scroll is very abrupt. Using jquery to have smooth scroll was not an option. So here's a native way to get the job done that supports all major browsers. Reference - caniuse
// get the "Div" inside which you wish to scroll (i.e. the container element)
const El = document.getElementById('xyz');
// Lets say you wish to scroll by 100px,
El.scrollTo({top: 100, behavior: 'smooth'});
// If you wish to scroll until the end of the container
El.scrollTo({top: El.scrollHeight, behavior: 'smooth'});
That's it!
And here's a working snippet for the doubtful -
document.getElementById('btn').addEventListener('click', e => {
e.preventDefault();
// smooth scroll
document.getElementById('container').scrollTo({top: 175, behavior: 'smooth'});
});
/* just some styling for you to ignore */
.scrollContainer {
overflow-y: auto;
max-height: 100px;
position: relative;
border: 1px solid red;
width: 120px;
}
body {
padding: 10px;
}
.box {
margin: 5px;
background-color: yellow;
height: 25px;
display: flex;
align-items: center;
justify-content: center;
}
#goose {
background-color: lime;
}
<!-- Dummy html to be ignored -->
<div id="container" class="scrollContainer">
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div id="goose" class="box">goose</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
</div>
<button id="btn">goose</button>
Update: As you can perceive in the comments, it seems that Element.scrollTo() is not supported in IE11. So if you don't care about IE11 (you really shouldn't, Microsoft is retiring IE11 in June 2022), feel free to use this in all your projects. Note that support exists for Edge! So you're not really leaving your Edge/Windows users behind ;)
Reference
To scroll an element into view of a div, only if needed, you can use this scrollIfNeeded function:
function scrollIfNeeded(element, container) {
if (element.offsetTop < container.scrollTop) {
container.scrollTop = element.offsetTop;
} else {
const offsetBottom = element.offsetTop + element.offsetHeight;
const scrollBottom = container.scrollTop + container.offsetHeight;
if (offsetBottom > scrollBottom) {
container.scrollTop = offsetBottom - container.offsetHeight;
}
}
}
document.getElementById('btn').addEventListener('click', ev => {
ev.preventDefault();
scrollIfNeeded(document.getElementById('goose'), document.getElementById('container'));
});
.scrollContainer {
overflow-y: auto;
max-height: 100px;
position: relative;
border: 1px solid red;
width: 120px;
}
body {
padding: 10px;
}
.box {
margin: 5px;
background-color: yellow;
height: 25px;
display: flex;
align-items: center;
justify-content: center;
}
#goose {
background-color: lime;
}
<div id="container" class="scrollContainer">
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div id="goose" class="box">goose</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
<div class="box">duck</div>
</div>
<button id="btn">scroll to goose</button>
Code should be:
var divElem = document.getElementById('scrolling_div');
var chElem = document.getElementById('element_within_div');
var topPos = divElem.offsetTop;
divElem.scrollTop = topPos - chElem.offsetTop;
You want to scroll the difference between child top position and div's top position.
Get access to child elements using:
var divElem = document.getElementById('scrolling_div');
var numChildren = divElem.childNodes.length;
and so on....
If you are using jQuery, you could scroll with an animation using the following:
$(MyContainerDiv).animate({scrollTop: $(MyContainerDiv).scrollTop() + ($('element_within_div').offset().top - $(MyContainerDiv).offset().top)});
The animation is optional: you could also take the scrollTop value calculated above and put it directly in the container's scrollTop property.
We can resolve this problem without using JQuery and other libs.
I wrote following code for this purpose:
You have similar structure ->
<div class="parent">
<div class="child-one">
</div>
<div class="child-two">
</div>
</div>
JS:
scrollToElement() {
var parentElement = document.querySelector('.parent');
var childElement = document.querySelector('.child-two');
parentElement.scrollTop = childElement.offsetTop - parentElement.offsetTop;
}
We can easily rewrite this method for passing parent and child as an arguments
Another example of using jQuery and animate.
var container = $('#container');
var element = $('#element');
container.animate({
scrollTop: container.scrollTop = container.scrollTop() + element.offset().top - container.offset().top
}, {
duration: 1000,
specialEasing: {
width: 'linear',
height: 'easeOutBounce'
},
complete: function (e) {
console.log("animation completed");
}
});
None of other answer fixed my issue.
I played around with scrollIntoView arguments and managed to found a solution. Setting inline to start and block to nearest prevents parent element (or entire page) to scroll:
document.getElementById(chr).scrollIntoView({
behavior: 'smooth',
block: 'nearest',
inline: 'start'
});
There are two facts :
1) Component scrollIntoView is not supported by safari.
2) JS framework jQuery can do the job like this:
parent = 'some parent div has css position==="fixed"' || 'html, body';
$(parent).animate({scrollTop: $(child).offset().top}, duration)
Here's a simple pure JavaScript solution that works for a target Number (value for scrollTop), target DOM element, or some special String cases:
/**
* target - target to scroll to (DOM element, scrollTop Number, 'top', or 'bottom'
* containerEl - DOM element for the container with scrollbars
*/
var scrollToTarget = function(target, containerEl) {
// Moved up here for readability:
var isElement = target && target.nodeType === 1,
isNumber = Object.prototype.toString.call(target) === '[object Number]';
if (isElement) {
containerEl.scrollTop = target.offsetTop;
} else if (isNumber) {
containerEl.scrollTop = target;
} else if (target === 'bottom') {
containerEl.scrollTop = containerEl.scrollHeight - containerEl.offsetHeight;
} else if (target === 'top') {
containerEl.scrollTop = 0;
}
};
And here are some examples of usage:
// Scroll to the top
var scrollableDiv = document.getElementById('scrollable_div');
scrollToTarget('top', scrollableDiv);
or
// Scroll to 200px from the top
var scrollableDiv = document.getElementById('scrollable_div');
scrollToTarget(200, scrollableDiv);
or
// Scroll to targetElement
var scrollableDiv = document.getElementById('scrollable_div');
var targetElement= document.getElementById('target_element');
scrollToTarget(targetElement, scrollableDiv);
given you have a div element you need to scroll inside, try this piece of code
document.querySelector('div').scroll(x,y)
this works with me inside a div with a scroll, this should work with you in case you pointed the mouse over this element and then tried to scroll down or up. If it manually works, it should work too
User Animated Scrolling
Here's an example of how to programmatically scroll a <div> horizontally, without JQuery. To scroll vertically, you would replace JavaScript's writes to scrollLeft with scrollTop, instead.
JSFiddle
https://jsfiddle.net/fNPvf/38536/
HTML
<!-- Left Button. -->
<div style="float:left;">
<!-- (1) Whilst it's pressed, increment the scroll. When we release, clear the timer to stop recursive scroll calls. -->
<input type="button" value="«" style="height: 100px;" onmousedown="scroll('scroller',3, 10);" onmouseup="clearTimeout(TIMER_SCROLL);"/>
</div>
<!-- Contents to scroll. -->
<div id="scroller" style="float: left; width: 100px; height: 100px; overflow: hidden;">
<!-- <3 -->
<img src="https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-logo.png?v=9c558ec15d8a" alt="image large" style="height: 100px" />
</div>
<!-- Right Button. -->
<div style="float:left;">
<!-- As (1). (Use a negative value of 'd' to decrease the scroll.) -->
<input type="button" value="»" style="height: 100px;" onmousedown="scroll('scroller',-3, 10);" onmouseup="clearTimeout(TIMER_SCROLL);"/>
</div>
JavaScript
// Declare the Shared Timer.
var TIMER_SCROLL;
/**
Scroll function.
#param id Unique id of element to scroll.
#param d Amount of pixels to scroll per sleep.
#param del Size of the sleep (ms).*/
function scroll(id, d, del){
// Scroll the element.
document.getElementById(id).scrollLeft += d;
// Perform a delay before recursing this function again.
TIMER_SCROLL = setTimeout("scroll('"+id+"',"+d+", "+del+");", del);
}
Credit to Dux.
Auto Animated Scrolling
In addition, here are functions for scrolling a <div> fully to the left and right. The only thing we change here is we make a check to see if the full extension of the scroll has been utilised before making a recursive call to scroll again.
JSFiddle
https://jsfiddle.net/0nLc2fhh/1/
HTML
<!-- Left Button. -->
<div style="float:left;">
<!-- (1) Whilst it's pressed, increment the scroll. When we release, clear the timer to stop recursive scroll calls. -->
<input type="button" value="«" style="height: 100px;" onclick="scrollFullyLeft('scroller',3, 10);"/>
</div>
<!-- Contents to scroll. -->
<div id="scroller" style="float: left; width: 100px; height: 100px; overflow: hidden;">
<!-- <3 -->
<img src="https://cdn.sstatic.net/Sites/stackoverflow/company/img/logos/so/so-logo.png?v=9c558ec15d8a" alt="image large" style="height: 100px" />
</div>
<!-- Right Button. -->
<div style="float:left;">
<!-- As (1). (Use a negative value of 'd' to decrease the scroll.) -->
<input type="button" value="»" style="height: 100px;" onclick="scrollFullyRight('scroller',3, 10);"/>
</div>
JavaScript
// Declare the Shared Timer.
var TIMER_SCROLL;
/**
Scroll fully left function; completely scrolls a <div> to the left, as far as it will go.
#param id Unique id of element to scroll.
#param d Amount of pixels to scroll per sleep.
#param del Size of the sleep (ms).*/
function scrollFullyLeft(id, d, del){
// Fetch the element.
var el = document.getElementById(id);
// Scroll the element.
el.scrollLeft += d;
// Have we not finished scrolling yet?
if(el.scrollLeft < (el.scrollWidth - el.clientWidth)) {
TIMER_SCROLL = setTimeout("scrollFullyLeft('"+id+"',"+d+", "+del+");", del);
}
}
/**
Scroll fully right function; completely scrolls a <div> to the right, as far as it will go.
#param id Unique id of element to scroll.
#param d Amount of pixels to scroll per sleep.
#param del Size of the sleep (ms).*/
function scrollFullyRight(id, d, del){
// Fetch the element.
var el = document.getElementById(id);
// Scroll the element.
el.scrollLeft -= d;
// Have we not finished scrolling yet?
if(el.scrollLeft > 0) {
TIMER_SCROLL = setTimeout("scrollFullyRight('"+id+"',"+d+", "+del+");", del);
}
}
This is what has finally served me
/** Set parent scroll to show element
* #param element {object} The HTML object to show
* #param parent {object} The HTML object where the element is shown */
var scrollToView = function(element, parent) {
//Algorithm: Accumulate the height of the previous elements and add half the height of the parent
var offsetAccumulator = 0;
parent = $(parent);
parent.children().each(function() {
if(this == element) {
return false; //brake each loop
}
offsetAccumulator += $(this).innerHeight();
});
parent.scrollTop(offsetAccumulator - parent.innerHeight()/2);
}
I needed to scroll a dynamically loading element on a page so my solution was a little more involved.
This will work on static elements that are not lazy loading data and data being dynamically loaded.
const smoothScrollElement = async (selector: string, scrollBy = 12, prevCurrPos = 0) => {
const wait = (timeout: number) => new Promise(resolve => setTimeout(resolve, timeout));
const el = document.querySelector(selector) as HTMLElement;
let positionToScrollTo = el.scrollHeight;
let currentPosition = Math.floor(el.scrollTop) || 0;
let pageYOffset = (el.clientHeight + currentPosition);
if (positionToScrollTo == pageYOffset) {
await wait(1000);
}
if ((prevCurrPos > 0 && currentPosition <= prevCurrPos) !== true) {
setTimeout(async () => {
el.scrollBy(0, scrollBy);
await smoothScrollElement(selector, scrollBy, currentPosition);
}, scrollBy);
}
};
browser does scrolling automatically to an element that gets focus, so what you can also do it to wrap the element that you need to be scrolled to into <a>...</a> and then when you need scroll just set the focus on that a

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