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Random movement of circles created by the script

I have a function that craeates divs with a circle.
Now they are all created and appear at the beginning of the page and go further in order.
Next, I need each circle to appear in a random place. I did this.
Now I need all of them to move randomly across the entire page, I have difficulties with this.
Here is an example of how everything works for one element that is already on the page.
https://jsfiddle.net/quej8wko/
But when I add this code, all my created circles don't move.
I get an error:
"message": "Uncaught TypeError: Cannot set properties of null (setting 'willChange')",
This is probably due to the fact that initially there are no circles on the page. How can I connect the code so that all created circles move?
//creating circles
var widthHeight = 40; // <-- circle width
var margin = 20; // <-- margin - is it necessary ?
var delta = widthHeight + margin;
function createDiv(id, color) {
let div = document.createElement('div');
var currentTop = 0;
var documentHeight = document.documentElement.clientHeight;
var documentWidth = document.documentElement.clientWidth;
div.setAttribute('class', id);
if (color === undefined) {
let colors = ['#35def2', '#35f242', '#b2f235', '#f2ad35', '#f24735', '#3554f2', '#8535f2', '#eb35f2', '#f2359b', '#f23547'];
div.style.backgroundColor = colors[Math.floor(Math.random() * colors.length)];
}
else {
div.style.backgroundColor = color;
}
div.classList.add("circle");
div.classList.add("animation");
// Get the random positions minus the delta
currentTop = Math.floor(Math.random() * documentHeight) - delta;
currentLeft = Math.floor(Math.random() * documentWidth) - delta;
// Keep the positions between -20px and the current positions
var limitedTop = Math.max(margin * -1, currentTop);
var limitedLeft = Math.max(margin * -1, currentLeft);
div.style.top = limitedTop + "px";
div.style.left = limitedLeft + "px";
document.body.appendChild(div);
}
let i = 0;
const oneSecond = 1000;
setInterval(() => {
i += 1;
createDiv(`circle${i}`)
}, oneSecond);
//move circles
function RandomObjectMover(obj, container) {
this.$object = obj;
this.$container = container;
this.container_is_window = container === window;
this.pixels_per_second = 250;
this.current_position = { x: 0, y: 0 };
this.is_running = false;
}
// Set the speed of movement in Pixels per Second.
RandomObjectMover.prototype.setSpeed = function(pxPerSec) {
this.pixels_per_second = pxPerSec;
}
RandomObjectMover.prototype._getContainerDimensions = function() {
if (this.$container === window) {
return { 'height' : this.$container.innerHeight, 'width' : this.$container.innerWidth };
} else {
return { 'height' : this.$container.clientHeight, 'width' : this.$container.clientWidth };
}
}
RandomObjectMover.prototype._generateNewPosition = function() {
// Get container dimensions minus div size
var containerSize = this._getContainerDimensions();
var availableHeight = containerSize.height - this.$object.clientHeight;
var availableWidth = containerSize.width - this.$object.clientHeight;
// Pick a random place in the space
var y = Math.floor(Math.random() * availableHeight);
var x = Math.floor(Math.random() * availableWidth);
return { x: x, y: y };
}
RandomObjectMover.prototype._calcDelta = function(a, b) {
var dx = a.x - b.x;
var dy = a.y - b.y;
var dist = Math.sqrt( dx*dx + dy*dy );
return dist;
}
RandomObjectMover.prototype._moveOnce = function() {
// Pick a new spot on the page
var next = this._generateNewPosition();
// How far do we have to move?
var delta = this._calcDelta(this.current_position, next);
// Speed of this transition, rounded to 2DP
var speed = Math.round((delta / this.pixels_per_second) * 100) / 100;
//console.log(this.current_position, next, delta, speed);
this.$object.style.transition='transform '+speed+'s linear';
this.$object.style.transform='translate3d('+next.x+'px, '+next.y+'px, 0)';
// Save this new position ready for the next call.
this.current_position = next;
};
RandomObjectMover.prototype.start = function() {
if (this.is_running) {
return;
}
// Make sure our object has the right css set
this.$object.willChange = 'transform';
this.$object.pointerEvents = 'auto';
this.boundEvent = this._moveOnce.bind(this)
// Bind callback to keep things moving
this.$object.addEventListener('transitionend', this.boundEvent);
// Start it moving
this._moveOnce();
this.is_running = true;
}
RandomObjectMover.prototype.stop = function() {
if (!this.is_running) {
return;
}
this.$object.removeEventListener('transitionend', this.boundEvent);
this.is_running = false;
}
// Init it
var x = new RandomObjectMover(document.querySelector(".circle"), window);
// Start it off
x.start();
.circle {
clip-path: circle(50%);
height: 40px;
width: 40px;
margin: 20px;
position: absolute;
}

I have modified the snippet which works as you expected.
There was a mistake where you were initializing and creating the object instance only once and none of the div elements that you created inside the setInterval function never got Instantiated.
I think you are just starting out with JavaScript with this sample project.
Below are few suggestions:
Learn to debug the code. You should be using dev tools by making use of debugger statement where it takes you to the source code to analyze the variable scope and stack during the runtime. console.log also helps in few situations.
I could see a lot of confusing naming convention (You have named the create div parameter as id but creating a div class using that id)
Try using ES6 features (class syntax is really good when writing OOP in JS although it's just a syntactic sugar for prototype)
//creating circles
var widthHeight = 40; // <-- circle width
var margin = 20; // <-- margin - is it necessary ?
var delta = widthHeight + margin;
function createAndInitializeDivObject(id, color) {
let div = document.createElement('div');
var currentTop = 0;
var documentHeight = document.documentElement.clientHeight;
var documentWidth = document.documentElement.clientWidth;
div.setAttribute('class', id);
if (color === undefined) {
let colors = ['#35def2', '#35f242', '#b2f235', '#f2ad35', '#f24735', '#3554f2', '#8535f2', '#eb35f2', '#f2359b', '#f23547'];
div.style.backgroundColor = colors[Math.floor(Math.random() * colors.length)];
}
else {
div.style.backgroundColor = color;
}
div.classList.add("circle");
div.classList.add("animation");
// Get the random positions minus the delta
currentTop = Math.floor(Math.random() * documentHeight) - delta;
currentLeft = Math.floor(Math.random() * documentWidth) - delta;
// Keep the positions between -20px and the current positions
var limitedTop = Math.max(margin * -1, currentTop);
var limitedLeft = Math.max(margin * -1, currentLeft);
div.style.top = limitedTop + "px";
div.style.left = limitedLeft + "px";
document.body.appendChild(div);
var x = new RandomObjectMover(document.querySelector(`.${id}`), window);
x.start();
}
let i = 0;
const oneSecond = 1000;
setInterval(() => {
i += 1;
createAndInitializeDivObject(`circle${i}`)
}, oneSecond);
//move circles
function RandomObjectMover(obj, container) {
this.$object = obj;
this.$container = container;
this.container_is_window = container === window;
this.pixels_per_second = 250;
this.current_position = { x: 0, y: 0 };
this.is_running = false;
}
// Set the speed of movement in Pixels per Second.
RandomObjectMover.prototype.setSpeed = function(pxPerSec) {
this.pixels_per_second = pxPerSec;
}
RandomObjectMover.prototype._getContainerDimensions = function() {
if (this.$container === window) {
return { 'height' : this.$container.innerHeight, 'width' : this.$container.innerWidth };
} else {
return { 'height' : this.$container.clientHeight, 'width' : this.$container.clientWidth };
}
}
RandomObjectMover.prototype._generateNewPosition = function() {
// Get container dimensions minus div size
var containerSize = this._getContainerDimensions();
var availableHeight = containerSize.height - this.$object.clientHeight;
var availableWidth = containerSize.width - this.$object.clientHeight;
// Pick a random place in the space
var y = Math.floor(Math.random() * availableHeight);
var x = Math.floor(Math.random() * availableWidth);
return { x: x, y: y };
}
RandomObjectMover.prototype._calcDelta = function(a, b) {
var dx = a.x - b.x;
var dy = a.y - b.y;
var dist = Math.sqrt( dx*dx + dy*dy );
return dist;
}
RandomObjectMover.prototype._moveOnce = function() {
// Pick a new spot on the page
var next = this._generateNewPosition();
// How far do we have to move?
var delta = this._calcDelta(this.current_position, next);
// Speed of this transition, rounded to 2DP
var speed = Math.round((delta / this.pixels_per_second) * 100) / 100;
//console.log(this.current_position, next, delta, speed);
this.$object.style.transition='transform '+speed+'s linear';
this.$object.style.transform='translate3d('+next.x+'px, '+next.y+'px, 0)';
// Save this new position ready for the next call.
this.current_position = next;
};
RandomObjectMover.prototype.start = function() {
if (this.is_running) {
return;
}
// Make sure our object has the right css set
this.$object.willChange = 'transform';
this.$object.pointerEvents = 'auto';
this.boundEvent = this._moveOnce.bind(this)
// Bind callback to keep things moving
this.$object.addEventListener('transitionend', this.boundEvent);
// Start it moving
this._moveOnce();
this.is_running = true;
}
RandomObjectMover.prototype.stop = function() {
if (!this.is_running) {
return;
}
this.$object.removeEventListener('transitionend', this.boundEvent);
this.is_running = false;
}
// Init it
var x = new RandomObjectMover(document.querySelector(".circle"), window);
// Start it off
x.start();
.circle {
width: 35px;
height: 35px;
border-radius: 35px;
background-color: #ffffff;
border: 3px solid purple;
position: absolute;
}
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" href="style.css">
</head>
<body>
<div class="circle"></div>
<script src="app.js"></script>
</body>
</html>

Progress bar not updating even with SetTimeout

I have this inside index.html
<body>
<script>
window.onload=function() {
let videoDiv = createVideoDiv()
document.getElementById("contentVideo").appendChild(videoDiv);
document.addEventListener("keydown", function(inEvent){
controlVideo(inEvent.keyCode);
});
}
</script>
<div id="progressBarWrapper">
<div id="progressBar"></div>
</div>
<div id="contentVideo"></div>
</body>
and this css
#progressBarWrapper {
width: 100%;
height:15px;
background-color: black;
}
#progressBar {
width: 0%;
height: 15px;
background-color: green;
}
this is how the video div is created:
function createVideoDiv() {
var video = document.createElement("VIDEO");
video.setAttribute('controls', '');
//video.setAttribute('autoplay', '');
video.setAttribute('preload', 'auto');
video.setAttribute('width', larguraVideo);
video.setAttribute('id', 'video');
var source = document.createElement("SOURCE");
source.setAttribute('src', obterVideoClicado());
source.setAttribute('type', 'video/mp4');
video.addEventListener('progress', function() {
var range = 0;
var bf = this.buffered;
var time = this.currentTime;
while(!(bf.start(range) <= time && time <= bf.end(range))) {
range += 1;
}
var loadStartPercentage = bf.start(range) / this.duration;
var loadEndPercentage = bf.end(range) / this.duration;
var loadPercentage = loadEndPercentage - loadStartPercentage;
setTimeout(ajustarProgressBar, 40, loadPercentage * 100);
});
video.addEventListener('loadeddata', function() {
var myBar = document.getElementById("progressBarWrapper");
myBar.style = "display:none;";
video.play();
});
video.appendChild(source);
return video;
}
this is how the progress bar is adjusted
function ajustarProgressBar(valor) {
var progressBar = document.getElementById("progressBar");
progressBar.style.width = valor + "%";
}
Even the progress bar is being fired by
setTimeout(ajustarProgressBar, 40, loadPercentage * 100);
the progress bar is not updating and stays 0% all the time.
The progress bar is to be adjusted by the video download progress.
The video progress is working fine. I have printed that to console and the values are changing as the video download progresses.

You have to pass param to function:
var valor = loadPercentage * 100;
var delay = 100;
setTimeout(() => ajustarProgressBar(valor), delay);
--Edit
Your video progress event listener would now look like:
video.addEventListener('progress', function() {
var range = 0;
var bf = this.buffered;
var time = this.currentTime;
while(!(bf.start(range) <= time && time <= bf.end(range))) {
range += 1;
}
var loadStartPercentage = bf.start(range) / this.duration;
var loadEndPercentage = bf.end(range) / this.duration;
var loadPercentage = loadEndPercentage - loadStartPercentage;
var valor = loadPercentage * 100;
var delay = 100;
setTimeout(() => ajustarProgressBar(valor), delay);
});

The setTimeout function takes 2 parameters:
The function to call after the delay time
The delay time in milliseconds
So to call your function you must make a function that will call your function like this:
setTimeout(() => ajustarProgresBar(loadPercentage * 100), 40);
So in your code it might look like this:
var loadStartPercentage = bf.start(range) / this.duration;
var loadEndPercentage = bf.end(range) / this.duration;
var loadPercentage = loadEndPercentage - loadStartPercentage;
setTimeout(() => ajustarProgressBar(loadPercentage*100), 40);

How to call a function only for the first time - JavaScript

Note: I need to achieve this with pure javascript, I know there is a .one() method in jquery to do this, but I need the same output in pure javascript.
Scenario: I am trying to call a function when a user scrolls and reaches to the 3/4 part or more of the page, but the problem rises when user reaches that part, We all know they can't be pixel perfect so, after the condition is met, the function gets executed per pixel scroll.
I want that to execute only once the condition is met, then add a section at the bottom of the page, and then again user should reach the bottom and the function should get executed only once and so on...
Snippet:
var colors = ['skyblue', 'powderblue', 'lightgreen', 'indigo', 'coral'];
var addPage = function() {
var page = document.createElement('div');
page.classList.add('page');
page.style.backgroundColor = colors[Math.floor(Math.random() * colors.length)];
document.body.append(page);
console.log('added a new page');
}
var scrollAndAdd = function() {
if (window.scrollY < (window.innerHeight * (3 / 4))) {
// execute addPage only once for each attempt; it's creating infinite pages
addPage();
}
}
window.addEventListener('scroll', scrollAndAdd);
* {
margin: 0;
padding: 0;
}
.page {
height: 100vh;
}
<div class='page' style='background-color: lightgreen'></div>
<div class='page' style='background-color: skyblue'></div>

You don't really need logic to run the function just once; instead, use a different expression to determine whether to add the page. Once the page is added that same expression should no longer evaluate to true until more scrolling is done.
NB: I also changed a bit the random pick logic.
var colors = ['powderblue', 'lightgreen', 'indigo', 'coral', 'skyblue'];
var addPage = function() {
var page = document.createElement('div');
page.classList.add('page');
// Make sure the same color is not selected twice in sequence:
var colorIndex = Math.floor(Math.random() * (colors.length-1));
var color = colors.splice(colorIndex,1)[0];
colors.push(color);
page.style.backgroundColor = color;
document.body.append(page);
}
var scrollAndAdd = function() {
if (window.scrollY > document.body.clientHeight - window.innerHeight - 10) {
addPage();
}
}
window.addEventListener('scroll', scrollAndAdd);
* {
margin: 0;
padding: 0;
}
.page {
height: 100vh;
}
<div class='page' style='background-color: lightgreen'></div>
<div class='page' style='background-color: skyblue'></div>

I hope it will help you:
var colors = ['skyblue', 'powderblue', 'lightgreen', 'indigo', 'coral'];
var addPage = function() {
var page = document.createElement('div');
page.classList.add('page');
page.style.backgroundColor = colors[Math.floor(Math.random() * colors.length)];
document.body.append(page);
console.log('added a new page');
}
var scrollAndAdd = function() {
var a = document.body.clientHeight - window.innerHeight * (5 / 4)
if (window.scrollY > a) {
addPage();
}
}
window.addEventListener('scroll', scrollAndAdd);
* {
margin: 0;
padding: 0;
}
.page {
height: 100vh;
}
<div class='page' style='background-color: lightgreen'></div>
<div class='page' style='background-color: skyblue'></div>

Well how about curry it up with local flag.
var colors = ['skyblue', 'powderblue', 'lightgreen', 'indigo', 'coral'];
const localCurry = function(func, immediateAction) {
var flag;
return function() {
var context = this, args = arguments;
var callNow = immediateAction && !flag;
flag = true;
if (callNow) func.apply(context, args);
}
}
var addPage = localCurry(function() {
var page = document.createElement('div');
page.classList.add('page');
page.style.backgroundColor = colors[Math.floor(Math.random() * colors.length)];
document.body.append(page);
console.log('added a new page');
}, true);
var scrollAndAdd = function() {
var a = document.body.clientHeight - window.innerHeight * (5 / 4)
if (window.scrollY > a) {
addPage();
}
}
window.addEventListener('scroll', scrollAndAdd);
Now you do have option to reset the flag based on timer or custom logic.

style.pointerEvents not functioning

I'm trying to make an element that shrinks as you click it more and more. Once it reaches a threshold of 1%, it should reappear in full length and not be clickable. the style.pointerEvents is not working. (This is code added in, in order to solve an issue.) This is all of the code, there must be conflicting variables or something. But the main premise is to shake the element and shrink and then regrow and disable itself and after a waiting period enable itself.
`var rotated = false;
var height = 24.6;
var width = 15
function clickedhub() {
clicked();
timeout();
}
function clicked() {
document.getElementById('box').onclick = function() {
var div = document.getElementById('box'),
deg = rotated ? 0 : 10;
div.style.webkitTransform = 'rotate('+deg+'deg)';
div.style.msTransform = 'rotate('+deg+'deg)';
div.style.oTransform = 'rotate('+deg+'deg)';
div.style.transform = 'rotate('+deg+'deg)';
}
setInterval(res, 140);
function res() {
document.getElementById('box').style = function() {
var div = document.getElementById('box'),
deg = rotated ? 0 : 0;
div.style.webkitTransform = 'rotate('+deg+'deg)';
div.style.mozTransform = 'rotate('+deg+'deg)';
div.style.msTransform = 'rotate('+deg+'deg)';
div.style.oTransform = 'rotate('+deg+'deg)';
div.style.transform = 'rotate('+deg+'deg)';
}
}
}
function timeout() {
document.getElementById('box').onclick = function() {
var div = document.getElementById('box');
width = width / 1.5;
height = height / 1.5;
}
}
setInterval(gamerule, 10);
function gamerule() {
var div = document.getElementById('box');
if (width <= 1) {
div.removeEventListener("click", gamerule);
width = 100;
height = 100;
} else {
width--;
height--;
}
div.style.width = width + '%';
div.style.height = height + '%';
div.addEventListener("click", gamerule);
}
`

This should work for you
//setInterval(gamerule, 10);
let width = 100;
let height = 100;
var div = document.getElementById('box');
function gamerule() {
if (width <= 1) {
div.removeEventListener("click", gamerule);
width = 100;
height = 100;
} else {
width--;
height--;
}
div.style.width = width + '%';
div.style.height = height + '%';
}
div.addEventListener("click", gamerule);
#box{
background-color:red;
width:100%;
height:100%;
}
#container{
width:500px;
height:500px;
}
Click on the red box
<div id="container" >
<div id="box">
</div>
</div>

How to move an image depending on mouse location using JS?

I would like an image to move to the left if the mouse is to the left of the screen and to the right if the mouse to the right of the screen, using javascript, here is the code I have so far:
var dirx = 0;
var spdx = 35;
var imgLeftInt;
var imgTopInt;
var imgHeight;
var imgWidth;
var divWidth;
var divHeight;
var t;
var tempX;
var tempY;
So I'm pretty sure I'm not missing any variables...
function animBall(on) {
imgLeftInt = parseInt(document.images['logo'].style.left);
imgTopInt = parseInt(document.images['logo'].style.top);
imgHeight = parseInt(document.images['logo'].height);
imgWidth = parseInt(document.images['logo'].width);
divWidth = parseInt(document.images['container'].width);
if (tempX > 779){
dirx = 1;
}
else if(tempX < 767){
dirx = 2;
}
else {
spdx = 0;
}
So if tempX, which should be the x coordinate of the mouse location, is bigger than 779, which is the halfway point of the div tag, the image should go right. If it's less than that, it should go left, and otherwise, the speed should be zero, as in it should stay still.
if(dirx == 1){
goRight();
} else if(dirx == 2) {
goLeft();
}
}
function getMouseXY(e) {
tempX = e.clientX;
tempY = e.clientY;
}
I found hundreds of different ways to get the mouse location, but this was off W3C so I assume it works.
function goRight() {
document.images['logo'].style.left = imgLeftInt+spdx +"px";
if (imgLeftInt > (divWidth-imgWidth)){
dirx = 2;
spdx= 20;
}
}
function goLeft() {
document.images['logo'].style.left = (imgLeftInt-spdx) +"px";
if (imgLeftInt < 5){
dirx = 1;
spdx= 20;
}
}
</script>
So that's my whole script.
<div id="container" onmousemove="getMouseXY(event);" width="1546" height="423">
Start Animation Stop Animation <br />
<img src="http://qabila.tv/images/logo_old.png" style="position:absolute;left:10px;top:20px;" id="logo" />
</div>
I left the dependency on the mouse location to the very end so the animation script works fine (or at least worked, unless I broke something trying to get it to read the mouse location).
Any ideas what I'm doing wrong??
If it's any help, I've hosted the code here.

I went to your link and tried debugging your code. I get an error on line 21 because your document has no "container" image ("container" is a div).
At the start of your question, you said you wanted to know mouse position relative to center of "screen". For that, you'd probably want to use window.innerWidth instead of the width attribute that you set on your div.

Well that needed a whole load of work, anyway, I have done some of it for you and you can now see things partially working, but you will need to play with it on jsfiddle. Perhaps you can now open some specific questions regarding getting this to work.
<div id="container" width="1546" height="423"> <a id="start" href="#">Start Animation</a> <a id="stop" href="#">Stop Animation</a>
<br />
<img src="http://qabila.tv/images/logo_old.png" style="position:absolute;left:10px;top:20px;" id="logo" />
</div>
/*jslint sub: true, maxerr: 50, indent: 4, browser: true */
/*global */
(function () {
"use strict";
var start = document.getElementById("start"),
stop = document.getElementById("stop"),
container = document.getElementById("container"),
logo = document.getElementById("logo"),
dirx = 0,
spdx = 35,
imgLeftInt,
imgTopInt,
imgHeight,
imgWidth,
divWidth,
divHeight,
t,
tempX,
tempY;
function getMouseXY(e) {
tempX = e.clientX;
tempY = e.clientY;
}
function goRight() {
logo.style.left = imgLeftInt + spdx + "px";
if (imgLeftInt > (divWidth - imgWidth)) {
dirx = 2;
spdx = 20;
}
}
function goLeft() {
logo.style.left = (imgLeftInt - spdx) + "px";
if (imgLeftInt < 5) {
dirx = 1;
spdx = 20;
}
}
// attribute on unused
function animBall(on) {
imgLeftInt = parseInt(logo.style.left, 10);
imgTopInt = parseInt(logo.style.top, 10);
imgHeight = parseInt(logo.height, 10);
imgWidth = parseInt(logo.width, 10);
divWidth = parseInt(container.width, 10);
if (tempX > 779) {
dirx = 1;
} else if (tempX < 767) {
dirx = 2;
} else {
spdx = 0;
}
if (dirx === 1) {
goRight();
} else if (dirx === 2) {
goLeft();
}
}
function startAnim() {
t = setInterval(animBall, 80);
}
start.addEventListener("click", startAnim, false);
function stopAnim() {
clearInterval(t);
}
stop.addEventListener("click", stopAnim, false);
container.addEventListener("mousemove", getMouseXY, false);
}());

Why don't you usee the html5 canvas and gee.js
Here's the js fiddle result (it may take a while to load, but that's fault of jsfiddle, the script will load much faster once on your website): http://jsfiddle.net/wLCeE/7/embedded/result/
and here's the much simpler code to make it work:
var g = new GEE({
width: 500,
height: 423,
container: document.getElementById('canvas')
});
var img = new Image(); // Create new img element
img.onload = function () {
demo(g)
};
img.src = 'http://qabila.tv/images/logo_old.png'; // Set source path
function demo(g) {
var style = "left"
g.draw = function () {
if (g.mouseX > g.width / 2 && style == "left") styleRight()
else if (g.mouseX < g.width / 2 && style == "right") styleLeft()
}
function styleLeft() {
style = "left"
g.ctx.clearRect(0, 0, g.width, g.height)
g.ctx.drawImage(img, 0, 0)
}
function styleRight() {
style = "right"
g.ctx.clearRect(0, 0, g.width, g.height)
g.ctx.drawImage(img, g.width - img.width, 0)
}
}