Develop Reference

JS Array Remove from last and remove all buttons

I'm Like to add two buttons, like [REMOVE FROM LAST] and [REMOVE ALL] to remove marks on the image.
I have added a function to clear array, but when I click the button, nothing happen.
Marks are not removed, maybe this approach is not a correct way to do this.
Can anyone help me to do this please? Thanks to all.
var App = App || {};
App.points = []; // Use array to store objects like [{x,y,r}, {x,y,r} ...]
jQuery(function($) {
const $radius = $(".radius");
$('#image_preview').on('click', function(ev) {
const $this = $(this),
r = parseInt($radius.val().trim(), 10), // Parse as Integer radix 10
o = $this.offset(),
y = ev.pageY - o.top,
x = ev.pageX - o.left;
$("<div />", {
"class": "circle",
css: {
top: y,
left: x,
width: r * 2,
height: r * 2,
},
appendTo: $this // append to #image_preview!
});
// Append data to App.points
App.points.push({x,y,r});
// Test
console.log( App.points )
});
});
function clearArray() {
return App.points = []
}
#image_preview {
position: relative; /* Add this since child are absolute! */
background: #eee;
margin: 15px;
cursor: crosshair;
}
#image_preview img {
display: inline-block;
vertical-align: top;
}
.circle {
position: absolute;
background: rgba(255, 0, 0, 0.2) url("https://i.imgur.com/qtpC8Rf.png") no-repeat 50% 50%;
border-radius: 50%;
transform: translate(-50%, -50%); /* use translate instead of JS calculations */
}
.radius {
position: absolute;
}
<button onclick="clearArray();">Clear Array</button>Radius: <input type="text" value="20" class="radius" name="radius">
<div id="image_preview">
<img src="https://i.imgur.com/B7VsSq3.png" alt="graph">
</div>
<script src="//code.jquery.com/jquery-3.1.0.js"></script>

Collecting input data and showing it in div

I have some quantity inputs. I want to collect the data in "inputs" and show them in "#yolcudropdown". But I just can't pull the data. Inputs must be disabled. There should be no manual entry. I did something at the bottom of the "javascript" section. But I couldn't run it.
(function( $ ) {
$.fn.number = function(customOptions) {
var options = {
'containerClass' : 'number-style',
'minus' : 'number-minus',
'plus' : 'number-plus',
'containerTag' : 'div',
'btnTag' : 'span'
};
options = $.extend(true, options, customOptions);
var input = this;
input.wrap('<' + options.containerTag + ' class="' + options.containerClass + '">');
var wrapper = input.parent();
wrapper.prepend('<' + options.btnTag + ' class="' + options.minus + '"></' + options.btnTag + '>');
var minus = wrapper.find('.' + options.minus);
wrapper.append('<' + options.btnTag + ' class="' + options.plus + '"></' + options.btnTag + '>');
var plus = wrapper.find('.' + options.plus);
var min = input.attr('min');
var max = input.attr('max');
if(input.attr('step')){
var step = +input.attr('step');
} else {
var step = 1;
}
if(+input.val() <= +min){
minus.addClass('disabled');
}
if(+input.val() >= +max){
plus.addClass('disabled');
}
minus.click(function () {
var input = $(this).parent().find('input');
var value = input.val();
if(+value > +min){
input.val(+value - step);
if(+input.val() === +min){
input.prev('.' + options.minus).addClass('disabled');
}
if(input.next('.' + options.plus).hasClass('disabled')){
input.next('.' + options.plus).removeClass('disabled')
}
} else if(!min){
input.val(+value - step);
}
});
plus.click(function () {
var input = $(this).parent().find('input');
var value = input.val();
if(+value < +max){
input.val(+value + step);
if(+input.val() === +max){
input.next('.' + options.plus).addClass('disabled');
}
if(input.prev('.' + options.minus).hasClass('disabled')){
input.prev('.' + options.minus).removeClass('disabled')
}
} else if(!max){
input.val(+value + step);
}
});
};
})(jQuery);
$('.quntity-input').each(function () {
$(this).number();
});
/* THIS IS IMPORTANT */
$(document).ready(function() {
$(document).on('change', '.btw', function() {
$('#yolcudropdown').text($(this).val());
});
});
.number-style {
display: -ms-flexbox;
display: flex;
-ms-flex-wrap: wrap;
flex-wrap: wrap;
-ms-flex-pack: start !important;
justify-content: flex-start !important;
-ms-flex-align: center !important;
align-items: center !important;
}
.number-style .number-minus,
.number-style .number-plus {
height: 28px;
background: #ffffff;
border: 2px solid #e2e2e2 !important;
width: 28px;
-webkit-border-radius: 100%;
-moz-border-radius: 100%;
-ms-border-radius: 100%;
border-radius: 100%;
line-height: 23px;
font-size: 19px;
font-weight: 700;
text-align: Center;
border: none;
display: block;
cursor: pointer;
}
.number-style .number-minus:active,
.number-style .number-plus:active {
background: #e2e2e2;
}
.number-style .number-minus {
line-height: 20px;
}
.number-style .number-minus::after {
content: "-";
font-size: 10px;
}
.number-style .number-plus {
line-height: 18px;
}
.number-style .number-plus::after {
content: "+";
font-size: 10px;
}
.number-style .quntity-input {
width: 28px;
background: #e00f23;
-webkit-border-radius: 100%;
-moz-border-radius: 100%;
-ms-border-radius: 100%;
border-radius: 100%;
line-height: 21px;
font-size: 14px;
color: #ffffff;
font-weight: 700;
text-align: Center;
margin: 0 5px;
display: block;
cursor: pointer;
text-align: center;
border: none;
height: 28px;
font-weight: 600;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<input class="quntity-input btw" type="text" value="0" step="1" min="0" max="10">
<input class="quntity-input btw" type="text" value="0" step="1" min="0" max="10">
<div id="yolcudropdown">İnput quantity show this div</div>
"class" names of "input" elements are the same. I need to collect inputs with the same value and display them in the div instantly

HTMLInputElement
Input type "text" has no min max or step attributes, so your HTML is absolutely invalid. Try not to write It-works, I'm a framework -code. Respect the W3C standards.
Use type="number" (CSS pseudos can help you remove default spinner arrows from such elements)
Also step could be floats. Respect that and use parseFloat() in JS
CSS Flex to align stuff
Seems you know about CSS-flex, use it! Height, therefore- line-height... 19? 20? 23px? No. Just use flex.
CSS !important
!important is sign of poor coding style and should be left to Bootstrap only. Or to hopefully override Bootstrap styles - or in that cases when developers actually know what they are doing.
jQuery Plugins
jQuery plugins, I suggest to read the DOCS and get a deeper knowledge on how plugins work. Almost every jQuery method is a plugin. .hide() , .addClass()... I won't count them all. Plugins are chainable .removeClass("foo").stop().fadeTo(1), and so should be your .number() plugin.
To achieve chain-ability you simply return the bound this. PS: that's not jQuery... that's how JS works.
jQuery Plugins are not meant to be called inside a $.each() loop. $() is already a collection of DOM Nodes wrapped in a jQuery Object. No need to .each(). Same like: you would rather use $('a').css({color:'blue'}) instead of $('a').each(){ $(this).css({color: 'blue'}); });. Same effect, less code. Plugins.
jQuery DOM ready
jQuery(function($) { }); // DOM ready and $ alias in scope
Or if you don't care about ±IE, or you use ES6 syntax and a toolchain like Babel than: jQuery($ => { }) will suffice.
jQuery $ Object Constructor
jQuery allows you to define an HTMLElement that will eventually become a new DOM element wrapped with all the jQuery powers, Methods. Meaning that, if instead of passing a selector, you pass a more complex Tag-alike string (say: $("<span/>", {}); - jQuery will create an inMemory SPAN element and allow you to use the second parameter {} for most of the available jQuery Methods for that $Element. Let's use this!
jQuery plugin callbacks
If you want to provide a callback after a user changes the input value, provide a callback method. Don't force a programmer to write new spaghetti code, stick to the scope of your available Plugin internal Methods.
Sum Elements values
To sum Elements values you can use Array.prototype.reduce, just make sure to use an initialValue to prevent possible TypeErrors.
Example
Finally, here's the simplified CSS and improved JS:
(function($) {
$.fn.number = function(customOptions) {
const options = $.extend(true, {
containerTag: "div",
containerClass: "number-style",
minusClass: "number-minus", // consistency in wording!
minusText: "-", // Give power to the user!
plusClass: "number-plus",
plusText: "+",
btnTag: "button",
onChange() {}, // Provide a nifty callback!
}, customOptions);
this.each(function() { // Use .each() here!
const $input = $(this);
let val = parseFloat($input.value || 0); // floats!
const min = parseFloat($input.attr("min"));
const max = parseFloat($input.attr("max"));
const step = parseFloat($input.is("[step]") ? $input.attr("step") : 1);
const handleStyles = () => {
$minus.toggleClass('disabled', val <= min);
$plus.toggleClass('disabled', val >= max);
};
const change = () => {
val = Math.max(min, Math.min(max, val)); // Keep val in range.
$input.val(val); // Update input value
handleStyles(); // Update styles
options.onChange.call($input[0], val); // Trigger a public callback
}
const decrement = () => {
val -= step;
change();
};
const increment = () => {
val += step;
change();
};
const $minus = $(`<${options.btnTag}>`, {
type: "button",
title: "Decrement",
class: options.minusClass,
text: options.minusText,
on: {
click: decrement
}
});
const $plus = $(`<${options.btnTag}>`, {
class: options.plusClass,
title: "Increment",
text: options.plusText,
on: {
click: increment
}
});
const $wrapper = $(`<${options.containerTag}>`, {
class: options.containerClass,
});
$input.after($wrapper);
$wrapper.append($minus, $input.detach(), $plus); // Append all
handleStyles(); // handle initial styles
});
return this; // make your plugin chainable!
};
})(jQuery);
jQuery(function($) { // DOM ready and $ alias in scope
const $quantityInp = $('.quantity-input'); // Cache your elements!
const $dropdown = $('#yolcudropdown'); // Cache your elements!
$quantityInp.number({
onChange(val) { // our custom onChange callback!
const tot = $quantityInp.get().reduce((acc, el) => {
acc += parseFloat(el.value);
return acc;
}, 0);
$dropdown.text(tot);
}
});
});
/* QuickReset */ * { margin:0; box-sizing:border-box; }
.number-style input::-webkit-outer-spin-button,
.number-style input::-webkit-inner-spin-button {
-webkit-appearance: none;
}
.number-style {
display: flex;
}
.number-style > * {
height: 2em;
min-width: 2em;
border-radius: 2em;
display: flex; /* Use flex. */
justify-content: center;
text-align: center;
border: 0;
background: #ddd;
}
.number-style button {
background: #fff;
box-shadow: inset 0 0 0 2px #ccc;
cursor: pointer;
user-select: none;
/* no highlight, please! */
}
.number-style button:active {
background: #0bf;
}
.number-style input {
background: #e00f23;
color: #fff;
margin: 0 5px;
}
.number-style .disabled {
opacity: 0.2;
cursor: default;
}
/* Custom overrides: */
.number-style>* {
width: 2em;
/* just for roundness */
}
<input class="quantity-input" type="number" value="0" step="1" min="0" max="10">
<input class="quantity-input" type="number" value="0" step="1" min="0" max="10">
<div id="yolcudropdown">0</div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
Additional reading:
HTMLInputElement
Math/min
Math/max
jQuery plugin-creation
$ new-elements
Array/reduce
jQuery.toggleClass()
And PS: it's "quantity", not "quntity"

Vertical dragBar for resizing two divs

I wanted a vertical dragBar for resizing two divs. I have created an example for the same but I am facing an issue.
Actual : As and when I resize the the upper div and move the slider down, the area of parent div increases and hence a scroll bar is given.
Expected: When Resizing, if the slider is moved down, it should only show the data contained in the upper div and when slider is moved up, it should show the content of lower div and should not increase the over all length of the parent div.
var handler = document.querySelector('.handler');
var wrapper = handler.closest('.wrapper');
var boxA = wrapper.querySelector('.box1');
var boxB = wrapper.querySelector('.box2');
var isHandlerDragging = false;
document.addEventListener('mousedown', function(e) {
// If mousedown event is fired from .handler, toggle flag to true
if (e.target === handler) {
isHandlerDragging = true;
}
});
document.addEventListener('mousemove', function(e) {
// Don't do anything if dragging flag is false
if (!isHandlerDragging) {
return false;
}
// Get offset
var containerOffsetTop= wrapper.offsetTop;
var containerOffsetBottom= wrapper.offsetBottom;
// Get x-coordinate of pointer relative to container
var pointerRelativeXpos = e.clientY - containerOffsetTop;
var pointerRelativeXpos2 = e.clientY - e.offsetTop + e.offsetHeight;
var boxAminWidth = 30;
boxA.style.height = (Math.max(boxAminWidth, pointerRelativeXpos - 2)) + 'px';
boxA.style.flexGrow = 0;
boxB.style.height = (Math.max(boxAminWidth, pointerRelativeXpos2 - 8)) + 'px';
boxB.style.flexGrow = 0;
});
document.addEventListener('mouseup', function(e) {
// Turn off dragging flag when user mouse is up
isHandlerDragging = false;
});
body {
margin: 40px;
}
.wrapper {
background-color: #fff;
color: #444;
/* Use flexbox */
}
.box1, .box2 {
background-color: #444;
color: #fff;
border-radius: 5px;
padding: 20px;
font-size: 150%;
margin-top:2%;
/* Use box-sizing so that element's outerwidth will match width property */
box-sizing: border-box;
/* Allow box to grow and shrink, and ensure they are all equally sized */
}
.handler {
width: 20px;
height:7px;
padding: 0;
cursor: ns-resize;
}
.handler::before {
content: '';
display: block;
width: 100px;
height: 100%;
background: red;
margin: 0 auto;
}
<div class="wrapper">
<div class="box1">A</div>
<div class="handler"></div>
<div class="box2">B</div>
</div>
Hope I was clear in explaining the issue I am facing in my project. Any help is appreciated.

It looks like your on the right track. You just need to make the wrapper a flexbox with the flex direction column and assign it a height. Also box 2 needs to have a flex of 1 so it can grow and shrink as needed. Finally I needed to remove the code that set the flex grow to 0 in the JavaScript. Here is the result.
var handler = document.querySelector('.handler');
var wrapper = handler.closest('.wrapper');
var boxA = wrapper.querySelector('.box1');
var boxB = wrapper.querySelector('.box2');
var isHandlerDragging = false;
document.addEventListener('mousedown', function(e) {
// If mousedown event is fired from .handler, toggle flag to true
if (e.target === handler) {
isHandlerDragging = true;
}
});
document.addEventListener('mousemove', function(e) {
// Don't do anything if dragging flag is false
if (!isHandlerDragging) {
return false;
}
e.preventDefault();
// Get offset
var containerOffsetTop= wrapper.offsetTop;
var containerOffsetBottom= wrapper.offsetBottom;
// Get x-coordinate of pointer relative to container
var pointerRelativeXpos = e.clientY - containerOffsetTop;
var pointerRelativeXpos2 = e.clientY - e.offsetTop + e.offsetHeight;
var boxAminWidth = 30;
boxA.style.height = (Math.max(boxAminWidth, pointerRelativeXpos - 2)) + 'px';
boxB.style.height = (Math.max(boxAminWidth, pointerRelativeXpos2 - 8)) + 'px';
});
document.addEventListener('mouseup', function(e) {
// Turn off dragging flag when user mouse is up
isHandlerDragging = false;
});
body {
margin: 40px;
}
.wrapper {
background-color: #fff;
color: #444;
/* Use flexbox */
display: flex;
flex-direction: column;
height: 200px;
}
.box1, .box2 {
background-color: #444;
color: #fff;
border-radius: 5px;
padding: 20px;
font-size: 150%;
margin-top:2%;
/* Use box-sizing so that element's outerwidth will match width property */
box-sizing: border-box;
/* Allow box to grow and shrink, and ensure they are all equally sized */
}
.box2 {
flex: 1;
}
.handler {
width: 20px;
height:7px;
padding: 0;
cursor: ns-resize;
}
.handler::before {
content: '';
display: block;
width: 100px;
height: 100%;
background: red;
margin: 0 auto;
}
<div class="wrapper">
<div class="box1">A</div>
<div class="handler"></div>
<div class="box2">B</div>
</div>

animate opacity in and out on scroll

So I have a set of elements called .project-slide, one after the other. Some of these will have the .colour-change class, IF they do have this class they will change the background colour of the .background element when they come into view. This is what I've got so far: https://codepen.io/neal_fletcher/pen/eGmmvJ
But I'm looking to achieve something like this: http://studio.institute/clients/nike/
Scroll through the page to see the background change. So in my case what I'd want is that when a .colour-change was coming into view it would slowly animate the opacity in of the .background element, then slowly animate the opacity out as I scroll past it (animating on scroll that is).
Any suggestions on how I could achieve that would be greatly appreciated!
HTML:
<div class="project-slide fullscreen">
SLIDE ONE
</div>
<div class="project-slide fullscreen">
SLIDE TWO
</div>
<div class="project-slide fullscreen colour-change" data-bg="#EA8D02">
SLIDE THREE
</div>
<div class="project-slide fullscreen">
SLIDE TWO
</div>
<div class="project-slide fullscreen colour-change" data-bg="#cccccc">
SLIDE THREE
</div>
</div>
jQuery:
$(window).on('scroll', function () {
$('.project-slide').each(function() {
if ($(window).scrollTop() >= $(this).offset().top - ($(window).height() / 2)) {
if($(this).hasClass('colour-change')) {
var bgCol = $(this).attr('data-bg');
$('.background').css('background-color', bgCol);
} else {
}
} else {
}
});
});

Set some data-gb-color with RGB values like 255,0,0…
Calculate the currently tracked element in-viewport-height.
than get the 0..1 value of the inViewport element height and use it as the Alpha channel for the RGB color:
/**
* inViewport jQuery plugin by Roko C.B.
* http://stackoverflow.com/a/26831113/383904
* Returns a callback function with an argument holding
* the current amount of px an element is visible in viewport
* (The min returned value is 0 (element outside of viewport)
*/
;
(function($, win) {
$.fn.inViewport = function(cb) {
return this.each(function(i, el) {
function visPx() {
var elH = $(el).outerHeight(),
H = $(win).height(),
r = el.getBoundingClientRect(),
t = r.top,
b = r.bottom;
return cb.call(el, Math.max(0, t > 0 ? Math.min(elH, H - t) : (b < H ? b : H)), H);
}
visPx();
$(win).on("resize scroll", visPx);
});
};
}(jQuery, window));
// OK. Let's do it
var $wrap = $(".background");
$("[data-bg-color]").inViewport(function(px, winH) {
var opacity = (px - winH) / winH + 1;
if (opacity <= 0) return; // Ignore if value is 0
$wrap.css({background: "rgba(" + this.dataset.bgColor + ", " + opacity + ")"});
});
/*QuickReset*/*{margin:0;box-sizing:border-box;}html,body{height:100%;font:14px/1.4 sans-serif;}
.project-slide {
height: 100vh;
display: flex;
align-items: center;
justify-content: center;
}
.project-slide h2 {
font-weight: 100;
font-size: 10vw;
}
<div class="project-slides-wrap background">
<div class="project-slide">
<h2>when in trouble...</h2>
</div>
<div class="project-slide" data-bg-color="0,200,255">
<h2>real trouble...</h2>
</div>
<div class="project-slide">
<h2>ask...</h2>
</div>
<div class="project-slide" data-bg-color="244,128,36">
<h2>stack<b>overflow</b></h2>
</div>
</div>
<script src="//code.jquery.com/jquery-3.1.0.js"></script>

Looks like that effect is using two fixed divs so if you need something simple like that you can do it like this:
But if you need something more complicated use #Roko's answer.
var fixed = $(".fixed");
var fixed2 = $(".fixed2");
$( window ).scroll(function() {
var top = $( window ).scrollTop();
var opacity = (top)/300;
if( opacity > 1 )
opacity = 1;
fixed.css("opacity",opacity);
if( fixed.css('opacity') == 1 ) {
top = 0;
opacity = (top += $( window ).scrollTop()-400)/300;
if( opacity > 1 )
opacity = 1;
fixed2.css("opacity",opacity);
}
});
.fixed{
display: block;
width: 100%;
height: 200px;
background: blue;
position: fixed;
top: 0px;
left: 0px;
color: #FFF;
padding: 0px;
margin: 0px;
opacity: 0;
}
.fixed2{
display: block;
width: 100%;
height: 200px;
background: red;
position: fixed;
top: 0px;
left: 0px;
color: #FFF;
padding: 0px;
margin: 0px;
opacity: 0;
}
.container{
display: inline-block;
width: 100%;
height: 2000px;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="container">
Scroll me!!
</div>
<div class="fixed">
</div>
<div class="fixed2">
</div>

Semi-fixed text in a scrolling container

I've got a bunch of horizontal boxes containing text. The boxes are all in a horizontally scrolling container:
// generate some random data
var model = {
leftEdge: ko.observable(0)
};
model.rows = populateArray(10 + randInt(20), randRow);
ko.applyBindings(model);
$(function() {
$('.slide').on('scroll', function() {
model.leftEdge(this.scrollLeft);
})
})
function randRow() {
var events = populateArray(50 + randInt(100), randEvent);
var left = randInt(1000);
events.forEach(function(event) {
event.left = left;
left += 10 + event.width + randInt(1000);
});
return {
events: events
}
}
function randEvent() {
var word = randWord()
var width = 50 + Math.max(8 * word.length, randInt(200));
var event = {
left: 0,
width: width,
label: word
};
event.offset = ko.computed(function() {
// reposition the text to stay
// * within its container
// * fully on-screen (if possible)
var leftEdge = model.leftEdge();
return Math.max(0, Math.min(
leftEdge - event.left,
event.width - 8 * event.label.length
));
});
return event;
}
function randWord() {
var n = 2 + randInt(5);
var ret = "";
while (n-- > 0) {
ret += randElt("rmhntsk");
ret += randElt("aeiou");
}
return ret;
}
function randElt(arr) {
return arr[randInt(arr.length)];
}
function populateArray(n, populate) {
var arr = new Array(n);
for (var i = 0; i < n; i++) {
arr[i] = populate();
}
return arr;
}
function randInt(n) {
return Math.floor(Math.random() * n);
}
.slide {
max-width: 100%;
overflow: auto;
border: 5px solid black;
}
.row {
position: relative;
height: 25px;
}
.event {
position: absolute;
top: 2.5px;
border: 1px solid black;
padding: 2px;
background: #cdffff;
font-size: 14px;
font-family: monospace;
}
.event > span {
position: relative;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.2.0/knockout-min.js"></script>
<div class="slide" data-bind="foreach: rows">
<div class="row" data-bind="foreach: events">
<div class="event" data-bind="style: { left: left+'px', width: width+'px' }"><span data-bind="text:label, style: { left: offset() + 'px' }"></div>
</div>
</div>
What I'd like to do is as the user scrolls from left-to-right, reposition the text within each box that partially overlaps the left border of the visible window to keep the text as visible as possible.
Currently I'm doing this by manually repositioning each item of text.
Is there a cleaner way to do this using CSS?

A friend helped me come up with this solution.
In English, the idea is to add an overlay to each row that is positioned relatively to the frame of the scrolling box, rather than the contents.
Then we can place a label for any box that overlaps the left edge in this overlay and it will appear to smoothly move as the box underneath it scrolls.
// generate some random data
var model = {
leftEdge: ko.observable(0),
};
model.rows = populateArray(10 + randInt(20), randRow);
model.width = Math.max.apply(Math, $.map(model.rows, function(row) {
return row.width
}));
ko.applyBindings(model);
$(function() {
$('.slide').on('scroll', function() {
model.leftEdge(this.scrollLeft);
})
})
function randRow() {
var events = populateArray(50 + randInt(100), randEvent);
var left = randInt(1000);
events.forEach(function(event) {
event.left = left;
left += 10 + event.width + randInt(1000);
});
return {
events: events,
width: left
}
}
function randEvent() {
var word = randWord()
var width = 50 + Math.max(8 * word.length, randInt(200));
var event = {
width: width,
label: word,
};
event.tense = ko.computed(function() {
// reposition the text to stay#
// * within its container
// * fully on-screen (if possible)
var leftEdge = model.leftEdge();
return ['future', 'present', 'past'][
(leftEdge >= event.left) +
(leftEdge > event.left + event.width - 8 * event.label.length)
];
});
return event;
}
function randWord() {
var n = 2 + randInt(5);
var ret = "";
while (n-- > 0) {
ret += randElt("rmhntsk");
ret += randElt("aeiou");
}
return ret;
}
function randElt(arr) {
return arr[randInt(arr.length)];
}
function populateArray(n, populate) {
var arr = new Array(n);
for (var i = 0; i < n; i++) {
arr[i] = populate();
}
return arr;
}
function randInt(n) {
return Math.floor(Math.random() * n);
}
.wrapper {
position: relative;
border: 5px solid black;
font-size: 14px;
font-family: monospace;
}
.slide {
max-width: 100%;
overflow: auto;
}
.slide > * {
height: 25px;
}
.overlay {
position: absolute;
width: 100%;
left: 0;
}
.overlay .past {
display: none
}
.overlay .present {
position: absolute;
z-index: 1;
top: 5.5px;
left 0;
}
.overlay .future {
display: none
}
.row {
position: relative;
}
.event {
position: absolute;
top: 2.5px;
border: 1px solid black;
padding: 2px;
background: #cdffff;
height: 14px;
}
.event .past {
float: right;
}
.event .present {
display: none;
}
.event .future {
float: left;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.2.0/knockout-min.js"></script>
<div class="wrapper">
<div class="slide" data-bind="foreach: rows, style: { width: width + 'px' }">
<div class="overlay" data-bind="foreach: events">
<span data-bind="text:label, css: tense"></span>
</div>
<div class="row" data-bind="foreach: events">
<div class="event" data-bind="style: { left: left+'px', width: width+'px' }"><span data-bind="text:label, css: tense"></div>
</div>
</div></div>
This doesn't result in less javascript, but it does result in more efficient javascript, as class changes happen much less often than offset changes, so fewer updates to DOM elements are required.
You can avoid processing every "event" (in the above example) by doing some pre-partitioning of the horizontal space, and only updating events in the relevant partition.