Develop Reference

mousedown and touchstart not registering on mobile devices

I have created the following simple image comparison slider - modified from the version on w3schools (I know my mistake to use their code).
This all works fine on a desktop but when I try to use it on a mobile, nothing happens - it doesn't even register the console.log on the mousedown/touchstart (when I press on the slider button with my finger).
I was wondering if anyone could spot anything obvious with why it isn't working on mobile devices
(() => {
$.fn.imageComparisonSlider = function() {
var returnValue = this.each((index, item) => {
var $container = $(this);
var $overlay = $container.find('.image-comparison-slider__bottom-image');
var $slider = $('<span class="image-comparison-slider__slider"></span>');
var $window = $(window);
var touchStarted = false;
var width = $container.outerWidth();
$container.prepend($slider);
$container.on('mousedown touchstart', '.image-comparison-slider__slider', event => {
event.preventDefault();
console.log('touchstart');
touchStarted = true;
});
$window.on("mousemove touchmove", windowEvent => {
if (touchStarted) {
// get the cursor's x position:
let pos = getCursorPos(windowEvent);
// prevent the slider from being positioned outside the image:
if (pos < 0) pos = 0;
if (pos > width) pos = width;
// execute a function that will resize the overlay image according to the cursor:
slide(pos);
}
});
$window.on('mouseup touchend', event => {
event.preventDefault();
touchStarted = false;
});
function getCursorPos(e) {
var thisEvent = e || window.event;
// calculate the cursor's x coordinate, relative to the image
return thisEvent.pageX - $container.offset().left;
}
function slide(x) {
// set the width of the overlay
$overlay.width(width - x);
// position the slider
$slider[0].style.left = x + 'px';
}
function resetSlider() {
$overlay.width('50%');
$slider[0].style.left = $overlay.width() + 'px'
width = $container.outerWidth();
}
});
return returnValue;
};
})($);
$('.image-comparison-slider__container').imageComparisonSlider();
.image {
display: block;
width: 100%;
}
.image-comparison-slider__title {
text-align: center;
}
.image-comparison-slider__container,
.image-comparison-slider__image-holder {
position: relative;
}
.image-comparison-slider__bottom-image {
position: absolute;
overflow: hidden;
top: 0;
right: 0;
bottom: 0;
z-index: 1;
width: 50%;
}
.image-comparison-slider__caption {
position: absolute;
padding: 1rem;
color: white;
background: rgba(0, 0, 0, 0.6);
z-index: 2;
white-space: nowrap;
}
.image-comparison-slider__top-image .image-comparison-slider__caption {
top: 0;
left: 0;
}
.image-comparison-slider__bottom-image .image-comparison-slider__caption {
bottom: 0;
right: 0;
}
.image-comparison-slider__image {
display: block;
z-index: 1;
}
.image-comparison-slider__bottom-image .image {
position: absolute;
right: 0;
top: 0;
height: 100%;
width: auto;
}
.image-comparison-slider__slider {
position: absolute;
z-index: 3;
cursor: ew-resize;
/*set the appearance of the slider:*/
width: 50px;
height: 50px;
background-color: rgba(255, 96, 38, 0.8);
border-radius: 50%;
top: 50%;
left: 50%;
display: flex;
justify-content: center;
align-items: center;
transform: translate(-50%, -50%);
}
.image-comparison-slider__slider:after {
content: "< >";
color: white;
font-weight: bold;
font-size: 25px;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="image-comparison-slider__container">
<div class="image-comparison-slider__image-holder image-comparison-slider__top-image">
<img src="https://www.fillmurray.com/g/400/300" alt="A test image 1" class="image">
<div class="image-comparison-slider__caption">Left Image</div>
</div>
<div class="image-comparison-slider__image-holder image-comparison-slider__bottom-image">
<img src="https://www.fillmurray.com/400/300" alt="A test image 2" class="image">
<div class="image-comparison-slider__caption">Right Image</div>
</div>
</div>
Fiddle link for code

Ok have managed to fix this - the touch wasn't registering because of the transform so I changed that and just used negative margin as the button was a fixed size.
I then had to fix the thisEvent.pageX for android - so did a check with isNaN and then set it to e.originalEvent.touches[0].pageX if it was true.
Working version:
(() => {
$.fn.imageComparisonSlider = function() {
var returnValue = this.each((index, item) => {
var $container = $(this);
var $overlay = $container.find('.image-comparison-slider__bottom-image');
var $slider = $('<span class="image-comparison-slider__slider"></span>');
var $window = $(window);
var touchStarted = false;
var width = $container.outerWidth();
$container.prepend($slider);
$container.on('mousedown touchstart', '.image-comparison-slider__slider', event => {
event.preventDefault();
console.log('touchstart');
touchStarted = true;
});
$window.on("mousemove touchmove", windowEvent => {
if (touchStarted) {
// get the cursor's x position:
let pos = getCursorPos(windowEvent);
// prevent the slider from being positioned outside the image:
if (pos < 0) pos = 0;
if (pos > width) pos = width;
// execute a function that will resize the overlay image according to the cursor:
slide(pos);
}
});
$window.on('mouseup touchend', event => {
event.preventDefault();
touchStarted = false;
});
function getCursorPos(e) {
var thisEvent = e || window.event;
let xVal = thisEvent.pageX;
if (isNaN(xVal)) {
xVal = e.originalEvent.touches[0].pageX;
}
// calculate the cursor's x coordinate, relative to the image
return xVal - $container.offset().left;
}
function slide(x) {
// set the width of the overlay
$overlay.width(width - x);
// position the slider
$slider[0].style.left = x + 'px';
}
function resetSlider() {
$overlay.width('50%');
$slider[0].style.left = $overlay.width() + 'px'
width = $container.outerWidth();
}
});
return returnValue;
};
})($);
$('.image-comparison-slider__container').imageComparisonSlider();
.image {
display: block;
width: 100%;
}
.image-comparison-slider__title {
text-align: center;
}
.image-comparison-slider__container,
.image-comparison-slider__image-holder {
position: relative;
}
.image-comparison-slider__bottom-image {
position: absolute;
overflow: hidden;
top: 0;
right: 0;
bottom: 0;
z-index: 1;
width: 50%;
}
.image-comparison-slider__caption {
position: absolute;
padding: 1rem;
color: white;
background: rgba(0, 0, 0, 0.6);
z-index: 2;
white-space: nowrap;
}
.image-comparison-slider__top-image .image-comparison-slider__caption {
top: 0;
left: 0;
}
.image-comparison-slider__bottom-image .image-comparison-slider__caption {
bottom: 0;
right: 0;
}
.image-comparison-slider__image {
display: block;
z-index: 1;
}
.image-comparison-slider__bottom-image .image {
position: absolute;
right: 0;
top: 0;
height: 100%;
width: auto;
}
.image-comparison-slider__slider {
position: absolute;
z-index: 3;
cursor: ew-resize;
width: 50px;
height: 50px;
background-color: rgba(255, 96, 38, 0.8);
border-radius: 50%;
top: 50%;
left: 50%;
display: flex;
justify-content: center;
align-items: center;
margin: -25px 0 0 -25px;
}
.image-comparison-slider__slider:after {
content: "< >";
color: white;
font-weight: bold;
font-size: 25px;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="image-comparison-slider__container">
<div class="image-comparison-slider__image-holder image-comparison-slider__top-image">
<img src="https://www.fillmurray.com/g/400/300" alt="A test image 1" class="image">
<div class="image-comparison-slider__caption">Left Image</div>
</div>
<div class="image-comparison-slider__image-holder image-comparison-slider__bottom-image">
<img src="https://www.fillmurray.com/400/300" alt="A test image 2" class="image">
<div class="image-comparison-slider__caption">Right Image</div>
</div>
</div>

Image slider buttons not detecting click?

I have an image slider which is working fine rotating images alone using setInterval(). However, the buttons I've added to control which image is clicked aren't responding to click events.
I have used addEventListener and i'm currently using .on('click') but neither are working.
HTML:
<div id="sliderContainer">
<img src="assets/image0.png" id="sliderImage"/>
<div id="left_holder">
<img id="leftArrow" src="assets/arrow_left.png">
</div>
<div id="right_holder">
<img id="rightArrow" src="assets/arrow_right.png">
</div>
</div>
CSS:
#sliderContainer {
width: 700px;
height: 500px;
margin: 0 auto;
position: relative;
margin-bottom: 5% !important;
}
#sliderImage {
width: 700px;
height: 500px;
position: absolute;
}
#left_holder {
height: 500px;
width: 100px;
position: absolute;
left: 0px;
top: 0px;
}
#right_holder {
height: 500px;
width: 100px;
position: absolute;
right: 0px;
top: 0px;
}
#leftArrow {
height: 50px;
width: 50px;
position: absolute;
top: 45%;
left: 0px;
}
#rightArrow {
height: 50px;
width: 50px;
position: absolute;
top: 45%;
right: 0px;
}
JS:
$(document).ready(function () {
/*var leftbtn = document.getElementById("leftArrow");
var rightbtn = document.getElementById("rightArrow");*/
var imagecount = 0;
var total = 4;
console.log(imagecount);
function slider(x) {
var Image = document.getElementById('sliderImage');
imagecount = imagecount + x;
if (imagecount > total) {
imagecount = 0;
}
if(imagecount < 0) {
imagecount = total;
}
Image.src = "assets/image" + imagecount + ".png"
}
window.setInterval(function sliderA() {
var Image = document.getElementById('sliderImage');
imagecount = imagecount + 1;
console.log(imagecount);
if (imagecount > total) {
imagecount = 0;
}
if (imagecount < 0) {
imagecount = total;
}
Image.src = "assets/image" + imagecount + ".png"
},5000);
//EVENT LISTENERS
/*leftbtn.addEventListener("click", slider(-1));
rightbtn.addEventListener("click", slider(1));*/
$(document).on('click', '#leftArrow', slider(-1));
$(document).on('click', '#rightArrow', slider(1));
}); //Doc Ready

You have to pass an event handler (callback), not calling that function.
$(document).on('click', '#leftArrow', function() {
slider(-1);
});
$(document).on('click', '#rightArrow', function() {
slider(-1);
});

How to move two different images across the screen using JavaScript

I have been challenged with a website that requires me to make two images race at random across the screen to a finish line. I am required to make this happen using JavaScript. Unfortunately I have ran into some trouble here making this happen.
I have the script that allows a div container and an object "animate" (which is a small square) to move across the screen to the right as I am supposed to do. My question comes into play when trying to do this to two different images.
The goal is to have the animation I have created to apply to the images, I cannot figure out how to apply the functions to the images already placed on the page to make it seem as if they are racing on random intervals across the page to the finish line.
I understand the concept of the animation and the JavaScript behind it, I just dont understand how to make it apply to an image, and more than 1 image at that.
Please advise.
Here is my code that I am using: you can see that I left my demo animation on the page, and the two images I am looking to apply it to.
function myMove()
{
var elem = document.getElementById("animate");
var pos = 0;
var id = setInterval(frame, 5);
function frame()
{
if (pos == 350)
{
clearInterval(id);
}
else
{
pos++;
elem.style.left = pos + 'px';
}
}
}
<div id="traffic-light">
<div id="stopLight" class="bulb"></div>
<div id="yeildLight" class="bulb"></div>
<div id="goLight" class="bulb"></div>
</div>
<style>
body {
overflow: hidden;
}
#bluefish {
position: absolute;
top: 31pc;
width: 17pc;
left: -.5pc;
}
#turtle {
position: absolute;
width: 15pc;
top: 20pc;
}
body {
background-image: url("http://www.hpud.org/wp-content/uploads/2015/08/WaterBackground2.jpg")
}
.finishline {
position: absolute;
right: -12pc;
top: 18pc;
}
#traffic-light {
height: 10pc;
width: 4pc;
background-color: #333;
border-radius: 20pc;
position: absolute;
}
.bulb {
height: 2pc;
width: 2pc;
background-color: #111;
border-radius: 50%;
margin: 15px auto;
transition: background 500ms;
}
#container {
width: 400px;
height: 400px;
position: relative;
background: yellow;
}
#animate {
width: 50px;
height: 50px;
position: absolute;
background: red;
}
</style>
<img id="bluefish" src="http://clipartist.net/openclipart.org/2013/July/Blue_Fish_Goldfish.png">
<img id="turtle" src="http://www.clipartkid.com/images/386/turtle-free-stock-photo-illustration-of-a-green-sea-turtle-uPgZrm-clipart.png">
<img src="https://t1.rbxcdn.com/877010da8ce131dfcb3fa6a9b07fea89" class="finishline">
<p>
<button onclick="myMove()">Click Me</button>
</p>
<div id="container">
<div id="animate"></div>
</div>

Try this one:
function myMove()
{
var elemBluefish = document.getElementById("bluefish");
var elemBluefishWin = document.getElementById("bluefishwin");
var elemTurtle = document.getElementById("turtle");
var elemTurtleWin = document.getElementById("turtlewin");
var posBluefish = 0;
var posTurtle = 0;
var hasWinner = false;
elemBluefishWin.style.display = 'none';
elemTurtleWin.style.display = 'none';
var id = setInterval(frame, 5);
function frame()
{
if(posBluefish >= 350 && posTurtle >= 350)
{
clearInterval(id);
return;
}
if(posBluefish < 350)
{
posBluefish += Math.round(Math.random()*10);
if(posBluefish >= 350)
{
posBluefish = 350;
if(!hasWinner){
hasWinner = true;
elemBluefishWin.style.display = 'unset';
}
}
elemBluefish.style.left = posBluefish + 'px';
}
if(posTurtle < 350)
{
posTurtle += Math.round(Math.random()*10);
if(posTurtle >= 350)
{
posTurtle = 350;
if(!hasWinner){
hasWinner = true;
elemTurtleWin.style.display = 'unset';
}
}
elemTurtle.style.left = posTurtle + 'px';
}
}
}
<div id="traffic-light">
<div id="stopLight" class="bulb"></div>
<div id="yeildLight" class="bulb"></div>
<div id="goLight" class="bulb"></div>
</div>
<style>
body {
overflow: hidden;
}
#bluefish {
position: absolute;
top: 31pc;
width: 17pc;
left: -.5pc;
}
#turtle {
position: absolute;
width: 15pc;
top: 20pc;
}
#bluefishwin {
position: absolute;
right: 1pc;
top: 31pc;
display: none;
}
#turtlewin {
position: absolute;
right: 1pc;
top: 20pc;
display: none;
}
body {
background-image: url("http://www.hpud.org/wp-content/uploads/2015/08/WaterBackground2.jpg")
}
.finishline {
position: absolute;
right: -12pc;
top: 18pc;
}
#traffic-light {
height: 10pc;
width: 4pc;
background-color: #333;
border-radius: 20pc;
position: absolute;
}
.bulb {
height: 2pc;
width: 2pc;
background-color: #111;
border-radius: 50%;
margin: 15px auto;
transition: background 500ms;
}
/*#container {
width: 400px;
height: 400px;
position: relative;
background: yellow;
}
#animate {
width: 50px;
height: 50px;
position: absolute;
background: red;
}*/
</style>
<img id="bluefish" src="http://clipartist.net/openclipart.org/2013/July/Blue_Fish_Goldfish.png">
<img id="turtle" src="http://www.clipartkid.com/images/386/turtle-free-stock-photo-illustration-of-a-green-sea-turtle-uPgZrm-clipart.png">
<img src="https://t1.rbxcdn.com/877010da8ce131dfcb3fa6a9b07fea89" class="finishline">
<img id="bluefishwin" src="http://a.dryicons.com/images/icon_sets/coquette_part_3_icons_set/png/128x128/prize_winner.png">
<img id="turtlewin" src="http://a.dryicons.com/images/icon_sets/coquette_part_3_icons_set/png/128x128/prize_winner.png">
<p>
<button onclick="myMove()">Click Me</button>
</p>
<div id="container">
<div id="animate"></div>
</div>
It gets an element for each image and adds every 5ms a random amount of pixels (between 0 and 9) to each pos of image.
If both "racers" reached the target (350px) the interval is cleared and the race is over.
The winner gets an image displayed at the finish line.

an example:
function startRace() {
animateRacer("player1", true);
animateRacer("player2", true);
}
function animateRacer(playerId, reset) {
var elem = document.getElementById(playerId);
var pos = parseInt(elem.style.left, 10);
if (isNaN(pos) || reset) {
pos = 0;
}
//console.log(playerId + ': ' + pos);
if (pos < 450) {
pos += randStep(3);
elem.style.left = pos + 'px';
setTimeout('animateRacer("' + playerId + '")', randStep(5));
}
}
function randStep(max) {
var min = 1;
return Math.floor(Math.random() * (max - min)) + min;
}
body {
overflow: hidden;
}
#container {
width: 500px;
height: 160px;
position: relative;
background-color: yellow;
}
.player {
width: 50px;
height: 50px;
background-color: gray;
position: relative;
}
#player1 {
background-color: red;
top: 20px;
}
#player2 {
background-color: blue;
top: 40px;
}
<p>
<button onclick="startRace()">Start Race</button>
</p>
<div id="container">
<div id="player1" class="player"></div>
<div id="player2" class="player"></div>
</div>

function mover(obj) {
this.obj=obj;
this.pos = 0;
this.id = setInterval(this.frame, 5);
}
mover.prototype.frame=function() {
if (this.pos == 350) {
clearInterval(this.id);
} else {
this.pos++;
this.obj.style.left = this.pos + 'px';
}
}
}
Simply do:
img1=new mover(document.getElementById("pic1"));
You can repeat this with every image and you could store them into an array:
images=[];
function letsmove(){
images.push(new mover(someid));
...
}
And you can do this with all images on the site:
images=[];
function letsmove(){
domimages=document.getElementsByTagName("img");
domimages.forEach(function(img){
images.push(new mover(img));
});
}
}
See JS OOP and JS Prototyping for more explanation

Slideshow with random pics

So I made this little Slideshow with HTML/CSS/JS and I want to make it so that the 6 images appear randomly and not 1,2,3.. more like 2,3,1.. for example. Any help is appreciated. Many thanks in advance.
JS:
var imagecount = 1;
var total = 6;
function slide(x) {
var Image = document.getElementById('img');
imagecount = imagecount + x;
if(imagecount > total){imagecount = 1;}
if(imagecount < 1){imagecount = total;}
Image.src = "images/img"+ imagecount +".jpg";
ChangeText(imagecount);
}
window.setInterval(function slideA(x) {
var Image = document.getElementById('img');
imagecount = imagecount + 1;
if(imagecount > total){imagecount = 1;}
if(imagecount < 1){imagecount = total;}
Image.src = "images/img"+ imagecount +".jpg";
ChangeText(imagecount);
}, 3000);
function ChangeText(imgNum){
var allImagesAndText = {1: "Seltene römische Goldmünze", 2: "Römische Funde", 3: "Römische Wandmalerei", 4: "Tutanchamun", 5: "Cheops Pyramide", 6: "Ägyptische Malerei"};
document.getElementById("text1").innerHTML = allImagesAndText[imgNum];
}
CSS:
#container {
height: 450px;
width: 650px;
margin: 20px auto;
position: relative;
z-index: 1;
border: 10px solid #000;
border-radius: 10px;
}
#img {
height: 450px;
width: 650px;
}
#left_holder {
height: 450px;
width: 100px;
position: absolute;
left: 0px;
top: 0px;
}
#right_holder {
height: 450px;
width: 100px;
position: absolute;
right: 0px;
top: 0px;
}
.left {
height: 50px;
width: 50px;
position: absolute;
top: 40%;
left: 0px;
}
.right {
height: 50px;
width: 50px;
position: absolute;
top: 40%;
right: 0px;
}
#text1 {
position: absolute;
color: #fff;
font-size: 32px;
background-color: #000;
opacity: 0.5;
left: 37%;
z-index: 2;
}
HTML:
<div id="container">
<div id="text1">Text</div>
<img src="images/img1.jpg" id="img" />
<div id="left_holder">
<img onClick="slide(-1)" class="left" src="images/arrow_left.png" />
</div>
<div id="right_holder">
<img onClick="slide(1)" class="right" src="images/arrow_right.png" />
</div>
</div>

You can create unique random image slider. So it doesn't repeat image multiple times (Soham's answer is fine but it will repeat same image multiple times in a row).
Something like this:
var imagecount = 1;
var total = 6;
var uniqueRandoms = [];
function makeUniqueRandom() {
if (!uniqueRandoms.length) {
for (var i = imagecount; i <= total; i++) {
uniqueRandoms.push(i);
}
}
var index = Math.floor(Math.random() * uniqueRandoms.length);
var val = uniqueRandoms[index];
uniqueRandoms.splice(index, 1);
return val;
}
I used this SO answer.
And then in your code just call that function where you need it.
Example with your code just for autoslide is here https://jsfiddle.net/2gra4wk1/

You can add a function:-
function generateRandom(){
var x = Math.floor((Math.random() * 6) + 1); //generates random number from 1 to 6
return x;
}
And then call this function and use appropriately

JS slider tooltip

I have a slider with a pop-up that shows the current value of the slider.
but I want it only appears if I click on the slider and disappears when I do not click
is there a way to do it?
Below is my css js and html code
html:
<input type="range" id="myrange" name="myrange" class="zoom-range" min="0.25" max="2.00" step="0.01"/>
<output id="rangeHover" for="myrange" onmouseover="value = myrange.valueAsNumber;"></output>
js:
function modifyOffset() {
var el, newPoint, newPlace, offset, siblings, k;
width = this.offsetWidth;
newPoint = (this.value - this.getAttribute("min")) / (this.getAttribute("max") - this.getAttribute("min"));
offset = -1;
if (newPoint < 0) { newPlace = 0; }
else if (newPoint > 1) { newPlace = width; }
else { newPlace = width * newPoint + offset; offset -= newPoint;}
siblings = this.parentNode.childNodes;
for (var i = 0; i < siblings.length; i++) {
sibling = siblings[i];
if (sibling.id == this.id) { k = true; }
if ((k == true) && (sibling.nodeName == "OUTPUT")) {
outputTag = sibling;
}
}
outputTag.style.left = newPlace + "px";
outputTag.style.marginLeft = offset + "%";
outputTag.innerHTML = this.value;
}
function modifyInputs() {
var inputs = document.getElementsByTagName("input");
for (var i = 0; i < inputs.length; i++) {
if (inputs[i].getAttribute("type") == "range") {
inputs[i].onchange = modifyOffset;
// the following taken from http://stackoverflow.com/questions/2856513/trigger-onchange-event-manually
if ("fireEvent" in inputs[i]) {
inputs[i].fireEvent("onchange");
} else {
var evt = document.createEvent("HTMLEvents");
evt.initEvent("change", false, true);
inputs[i].dispatchEvent(evt);
}
}
}
}
window.onload = modifyInputs;
css:
output {
position: absolute;
background-image: linear-gradient(#FAFAD2, #FAFAD2);
width: 30px;
height: 15px;
text-align: center;
color: black;
border-radius: 5px;
display: block;
bottom: 120%;
margin-top:5000px;
font-size:11px;
left: 100%;
}
output:after {
content: "";
position: absolute;
width: 0px;
height: 0px;
border-top: 10px solid #FAFAD2;
border-left: 5px solid transparent;
border-right: 5px solid transparent;
top: 100%;
left: 100%;
margin-left: -26px;
margin-top: -1px;
}
#rangeHover{
display: block;
position: relative;
margin: -50px;
padding-right:10px;
padding-left:10px;
}
Thanks for help!

you could add to css:
output
{
display:none
}
input:hover + output
{
display:block;
}
UPDATE
tooltip visible on click:
input:active+ output
{
display:block;
}