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adding a classList to each element at a time in a array - plain js

I'm new to javascript and I've been trying something that although basic i can't really seem to understand why it isn't working.
I have three images and one button. Everytime I click that same button i want one of the images to disappear (using classList to add a Css class of display: none).
I'm trying to use the for loop but when I click the button they disappear at the same time. I've tried to create a variable inside the loop to store the index value but it returns an error.
Help please !!! Thanks
\\ Js
window.onload = function(){
var button = document.querySelector("button");
var imgs = document.querySelectorAll("#imagens img");
button.addEventListener("click",function(){
for(var i=0; i<imgs.length; i++){
imgs[i].classList.add("hidden");
//var currentImg = this.imgs[i];
//currentImg.classList.add("hidden");
}
})
};
\\\ CSS
.hidden{
display:none;
}
#images{
width:400px;
height:200px;
margin:0 auto;
}
#images img{
width:110px;
height:100px;
}
button{
margin:100px auto;
}
\\\ HTML
<div id="images">
<img src="https://media.defense.gov/2018/Jul/11/2001941257/780/780/0/180711-F-EF974- 0115.JPG" alt="">
<img src="https://live.staticflickr.com/3267/2590079513_12e2c73226_b.jpg" alt="">
<img src="https://upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Poinsettia_tree.jpg/360px-Poinsettia_tree.jpg" alt="">
<div>
<button type="button">change</button>
</div>
</div>

You can use setTimeout for this requirement and update the for loop inside button click like:
for (var i = 0; i < imgs.length; i++) {
(function(index) {
setTimeout(function() {
imgs[index].classList.add("hidden");
}, i * 1500);
})(i);
}
This way hidden class would be added to one image at a time after a delay of 1500 ms.

The problem is that every time the button is clicked, you loop through all the images so you add to all of them the hidden class. What you need to do is to create a global variable that can store the index of the last image you hid.
And when you click the button, you add the hidden class to the image at the index + 1 then increment that index for the next image. You don't need to have a for loop for that.
You also mistyped in your query selector, it should be
var imgs = document.querySelectorAll("#images img");
instead of
var imgs = document.querySelectorAll("#imagens img");
So here's what you should have :
let index = -1;
window.onload = function(){
var button = document.querySelector("button");
var imgs = document.querySelectorAll("#images img");
button.addEventListener("click",function(){
index++;
imgs[index].classList.add("hidden");
})
};
.hidden {
display: none;
}
#images {
width: 400px;
height: 200px;
margin: 0 auto;
}
#images img {
width: 110px;
height: 100px;
}
button {
margin: 100px auto;
}
<div id="images">
<img src="https://media.defense.gov/2018/Jul/11/2001941257/780/780/0/180711-F-EF974- 0115.JPG" alt="">
<img src="https://live.staticflickr.com/3267/2590079513_12e2c73226_b.jpg" alt="">
<img src="https://upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Poinsettia_tree.jpg/360px-Poinsettia_tree.jpg" alt="">
<div>
<button type="button">change</button>
</div>
</div>

Targeting one of multiple Classes / only part of the Class string - className vs classList

So I'm trying to put together a Javascript toggle for my photography portfolio site. My goal is to be able to click a button labeled Show Only Sunsets and hide every image without a "Sunsets" Class. The code I've come up with below ALMOST works, but there's a major flaw:
This code only preserves the visibility of images such as "1.jpg" below whose Class is exactly/only "Sunsets" (or "NSFW," or whatever). But often I'll need to give images more than one class, for example to differentiate verticals, or images that fall into multiple categories. So I need the code to preserve the visibility of any image such as "2.jpg" below which has "Sunsets" (or whatever) anywhere in its Class.
JS:
<script>
function filterOn(imageClass) {
var image = document.getElementsByTagName('figure');
for (i = 0; i < image.length; i++) {
if (image[i].className != imageClass) {
image[i].style.display = 'none';
}
}
document.getElementById(imageClass + '-off').innerHTML = 'Undo Filter';
document.getElementById(imageClass + '-off').setAttribute('onClick', "filterOff('" + imageClass + "')");
document.getElementById(imageClass + '-off').id = imageClass + '-on';
}
function filterOff(imageClass) {
var image = document.getElementsByTagName('figure');
for (i = 0; i < image.length; i++) {
if (image[i].className != imageClass) {
image[i].style.display = 'inline-block';
}
}
document.getElementById(imageClass + '-on').innerHTML = 'Show Only ' + imageClass;
document.getElementById(imageClass + '-on').setAttribute('onClick', "filterOn('" + imageClass + "')");
document.getElementById(imageClass + '-on').id = imageClass + '-off';
}
</script>
HTML:
<ul>
<li id="Sunsets-off" onClick="filterOn('Sunsets')">Show Only Sunsets</li>
<li id="NSFW-off" onClick="filterOn('NSFW')">Show Only NSFW</li>
</ul>
<img class="Sunsets" src="1.jpg">
<img class="vertical Sunsets" src="2.jpg">
<img class="NSFW vertical" src="3.jpg">
<img class="Architectural" src="4.jpg">
<img class="Sunsets Landscapes" src="5.jpg">
<img class="Abstract" src="6.jpg">
<img class="NSFW LondonAndrews" src="7.jpg">

That test:
if (image[i].className != imageClass) {
will indeed do a check against the whole class string.
There's the classList API for doing what you want, replacing your test with:
if (!image[i].classList.contains(imageClass)) {

I would simplify it by adding a class name to all images so you can easily target all the images, then use a toggled class to hide the images you don't want to see. this also gives you the ability to use css3 animations to fade the images you don't want to see.
function filterOn( clazz ){
// get all the images using the additional img class
var images = slice(document.getElementsByClassName('img'));
// hide all the images
var ret = images.map(function( image ){
image.classList.add('hide');
return image;
})
// reduce the images to only contain those you want to show
.filter(function( image ){
return image.classList.contains( clazz );
})
// show the image by removing the hide class
.forEach(function( image ){
image.classList.remove('hide');
});
}
// show all images
function showAll(){
var images = slice(document.getElementsByClassName('img'));
images.forEach(function( image ){
image.classList.remove('hide');
});
}
// helper function to get an array from an array like object
function slice( arrayLike ){
return Array.prototype.slice.call( arrayLike );
}
.img {
display: block;
float: left;
margin-left: .8em;
border: .3em solid #aaa;
}
.hide {
display: none;
}
.filters {
display: block;
width: 100%;
float: left;
}
.Sunsets {
border: .3em solid orange;
}
.NSFW {
border: .3em solid magenta;
}
<nav class="filters">
<button id="Sunsets-off" onClick="filterOn('Sunsets')">Show Only Sunsets</button>
<button id="NSFW-off" onClick="filterOn('NSFW')">Show Only NSFW</button>
<button id="show-all" onClick="showAll()">Show All</button>
</nav>
<!-- I added an img class to the images for ease of use later -->
<section class="images">
<img class="img Sunsets" src="http://placehold.it/50/50">
<img class="img vertical Sunsets" src="http://placehold.it/50/50">
<img class="img NSFW vertical" src="http://placehold.it/50/50">
<img class="img Architectural" src="http://placehold.it/50/50">
<img class="img Sunsets Landscapes" src="http://placehold.it/50/50">
<img class="img Abstract" src="http://placehold.it/50/50">
<img class="img NSFW LondonAndrews" src="http://placehold.it/50/50">
</section>

addClass jquery loop

I'm working on a web project that has a changing background image every few seconds. Problem is I don't know how to get the first image to return after all images are finished rotating. After the third image the screen goes white.
html :
<section class="slideshow">
<img src="img/img1.png" class="bgM show"/>
<img src="img/img2.png" class="bgM"/>
<img src="img/img3.jpg" class="bgM"/>
</section>
javascript
function switch() {
var $active = $('.slideshow IMG.show');
var $next = $active.next();
var $images = new Array();
var $length = $images.length;
$next.addClass('show');
$active.removeClass('show');
if ($images[$length].hasClass('show')) {
$images[0].addClass('show');
}
}
$(function() {
setInterval( "switch()", 8000 );
});

jsFiddle Demo
No need for the extra code. Just use an iterator with mod for the set of image elements.
$(function() {
var slide = $(".slideshow"), cur = 0;
setInterval(function(){
$('.show',slide).removeClass('show');
$('img',slide).eq((++cur)%3).addClass('show');
}, 1000 );//using 1000 just for demo purposes
});
.slideshow img.show{
border:2px solid red;
display:block;
}
.slideshow img{
display:none;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<section class="slideshow">
<img src="http://placehold.it/350x150" class="bgM show"/>
<img src="http://placehold.it/250x150" class="bgM"/>
<img src="http://placehold.it/150x150" class="bgM"/>
</section>

The first major issue is that your function switch is a reserved word (ie choose another name [I chose switch_images]).
Next you can check to see if the "next" image exists (.length). If it doesn't then set it to the first image in the slideshow:
<section class="slideshow">
<img src="img/img1.png" class="bgM show"/>
<img src="img/img2.png" class="bgM"/>
<img src="img/img3.jpg" class="bgM"/>
</section>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
<script type="text/javascript">
function switch_images() {
var $active = $('.slideshow IMG.show');
var $next = $active.next();
if(!$next.length){
$next = $('.slideshow IMG:first');
}
$active.removeClass('show');
$next.addClass('show');
}
$(function() {
setInterval( "switch_images()", 8000 );
});
</script>

Adding a CSS class to span tag when corresponding image is slide in

I have a two phase animation including a div full of images and to the right, a paragraph of 10 span sentences. The images are absolute, so they stack on top of each other and have a negative margin initially to hide the image, by overflow: hidden.
On phase 1 (when page loads and before user hovers over a span), the images are set at a 5 second interval per image to loop through the images in an infinite manner. This phase and it's interval will clear when the second phase happens, which is when you hover over a span tag, in which the corresponding image slides in to view.
I have phase 1 and phase 2 coded, but my question is: In phase 1, I have to implement it so that when it's animating through the images by default, the corresponding span tag has to have a CSS class just like when you hover over the span tag in phase 2.
Here is the code if anyone wants to fiddle around with it:
<!--begin:content-->
<div id="content">
<div id="pics">
<img src="ADD ANY IMAGE" id="defaultImg" alt="" />
<img src="ADD ANY IMAGE" id="hover_1_pic" alt="" />
<img src="ADD ANY IMAGE" id="hover_2_pic" alt="" />
<img src="ADD ANY IMAGE" id="hover_3_pic" alt="" />
<img src="ADD ANY IMAGE" id="hover_4_pic" alt="" />
<img src="ADD ANY IMAGE" id="hover_5_pic" alt="" />
<img src="ADD ANY IMAGE" id="hover_6_pic" alt="" />
<img src="ADD ANY IMAGE" id="hover_7_pic" alt="" />
<img src="ADD ANY IMAGE" id="hover_8_pic" alt="" />
<img src="ADD ANY IMAGE" id="hover_9_pic" alt="" />
<img src="ADD ANY IMAGE" id="hover_10_pic" alt="" />
</div>
<!--begin: homeText - block of span tags w/text referenced in jQuery -->
<div class="homeText">
<p>
<span id="hover_1" >evolve water.</span>
<span id="hover_2">stream the party.</span>
<br />
<span id="hover_3">let moms play.</span>
<span id="hover_4">play on big screens.</span>
<br />
<span id="hover_5">turn txt into sport.</span>
<span id="hover_6">have 18 wheels.</span>
<br />
<span id="hover_7">have chapters.</span>
<span id="hover_8">personify an issue.</span>
<br />
<span id="hover_9">transform neighborhoods.</span>
<br />
<span id="hover_10">become keepsakes</span>
</p>
</div>
</div><!--end content-->
CSS
#pics img {
height: 131px;
width: 334px;
position: absolute;
margin-left:-325px;
}
/* ADDED by ben sewards */
#pics {
height:179px;
width:335px;
position: relative;
overflow: hidden;
margin:0px;
padding-top:15px;
margin-left:49px;
float:left;
}
/* ADDED by ben sewards */
.homeText {
width:600px;
height:240px;
padding-left:15px;
padding-top: 10px;
overflow: hidden;
float:left;
}
.homeText p {
line-height: 115%;
font-family: #Adobe Fangsong Std R;
font-size: 2.6em;
font-weight:bolder;
color: #c0c0c0;
margin: 0px;
}
.homeText span:hover {
background-color:Lime;
color: White;
cursor: pointer;
}
.span-background-change {
background-color:Lime;
color: White;
}
JS Script
$('document').ready(function () {
slideIn('defaultImg');
timer = setInterval('slideInNext()', 5000);
functionHover();
});
var slideSpeed = 500;
var slideIn = function (id) {
$('#' + id).addClass('active').animate({ 'margin-left': '0px' }, { 'duration': slideSpeed, 'easing': 'swing', 'queue': true });
}
var slideOutCurrent = function () {
$('#pics img.active').removeClass('active').animate({ 'margin-left': '325px' }, { 'duration': slideSpeed, 'easing': 'swing', 'queue': true, 'complete': function () { $(this).css('margin-left', '-325px'); } });
}
var slideInNext = function () {
var curImage = $('#pics img.active');
var nextImage = curImage.next();
if (nextImage.length == 0) {
nextImage = $('#pics img:first');
}
slideOutCurrent();
slideIn(nextImage.attr('id'));
}
var queueToSlideIn = [];
var mouseOnTimer = null;
var mouseOffTimer = null;
var functionHover = function () {
$('.homeText span').hover(
//binding 2 handlers to hover event
function () { //when hovering over a span - mousenenter
clearTimeout(mouseOffTimer);
clearInterval(timer);
var thisId = $(this).attr('id');
mouseOnTimer = setTimeout(function () {
if (!$('#' + thisId + '_pic').hasClass('active')) {
addToQueue(thisId + '_pic');
}
}, 300);
},
function () { //when off of span - mouseleave
clearTimeout(mouseOnTimer);
mouseOffTimer = setTimeout(function () {
if (!$('#defaultImg').hasClass('active')) {
addToQueue('defaultImg');
}
}, 500);
}
);
$('.homeText span').click(function () {
//set current span on click
$span = $(this).attr('id');
//navigate to corresponding case study
var href = $('#' + $span + '_pic').attr('alt');
window.location.href = href;
});
}
var addToQueue = function (id) {
queueToSlideIn.push(id);
$('#pics').queue(function () { animateNext(); $(this).dequeue(); }).delay(slideSpeed);
}
var animateNext = function () {
if (queueToSlideIn.length > 0) {
var id = queueToSlideIn.shift();
slideOutCurrent();
slideIn(id);
}
};
Sorry if the indenting is messy.
Ben

I added anew class which is a duplicate of your hover class:
.homeText-hover {
background-color:Lime;
color: White;
cursor: pointer;
}
Then I added two line each to your SlideIn and slideOutCurrent functions:
var slideIn = function (id) {
var slId = id.split('_pic');
$('#' + slId[0]).addClass('homeText-hover');
$('#' + id).addClass('active').animate({ 'margin-left': '0px' }, { 'duration': slideSpeed, 'easing': 'swing', 'queue': true });
}
var slideOutCurrent = function () {
var slId = $('#pics img.active').attr('id').split('_pic');
$('#' + slId[0]).removeClass('homeText-hover');
$('#pics img.active').removeClass('active').animate({ 'margin-left': '325px' }, { 'duration': slideSpeed, 'easing': 'swing', 'queue': true, 'complete': function () { $(this).css('margin-left', '-325px'); } });
}
Your autoslide isn't working out in FF...

I like your solution, Ben. Another solution that uses the same principle of selecting identifying attributes would be to add a class, unique to each img-span pair, to each of the elements, so that each shares a specific class with its corresponding element.
Below is an explanation of the use of classes as flags, which I originally posted in a solution to a different question that has since been closed:
Classes as Flags
Adding a class to an element does not always mean that you are going to be giving it some new CSS styles. CSS is a language that USES CLASSES in order TO HELP identify elements to style a particular way; classes are NOT FOR THE SOLE PURPOSE of applying CSS to an element. Were this not the case, CSS would only be able to style elements through the use of classes, and not through the use of other selectors (IDs, parents, children, descendants, etc.).
Developers often use classes as "flags." Flags are a way of signaling something about a particular element without having to store that information in a variable. For example, imagine you have a list of elements and all the elements are styled exactly the same, via a CSS class. If a developer wanted to mark every other element in this list in a particular way (for some later use), without changing the style of the elements, he may choose to add a second class called "alternate" to the elements.
You can add as many classes as you want to an element and it is totally accepted coding style to add multiple classes that do not have any associated styles (provided that such classes are for some other use -scripting, etc.).

Added this snippet of code to my slideInNext function for desired results:
if (nextImage.attr('id') != "defaultImg") {
//add class to corresponding span tag of current image
var spanId = nextImage.attr('id');
//corresponing span of next image
spanId = spanId.substring(0, spanId.length - 4);
$('#' + spanId).addClass('span-background-change');
}
I just used the substring method in javascript to pull apart the images attribute id and place it in a local variable to represent the span id.

Change an image with onclick()

I want to change an image to some other image when i click on the object. the code is stacked in the following order:
<li><img><some text></img></li>
<li><img><some text></img></li>
<li><img><some text></img></li>
<li><img><some text></img></li>
<li><img><some text></img></li>
What I wish to do is, when I click on the <li> i want to change the image to a coloured version of the image, i.e. some other image. Now, I know I can use JQuery/JS to accomplish it. But I don't want a huge amount of JS code to accomplish something so simple.
Can it be done using something simpler? Like pseudo selectors? .active class?
I cannot seem to think of it.

To change image onclik with javascript you need to have image with id:
<p>
<img alt="" src="http://www.userinterfaceicons.com/80x80/minimize.png"
style="height: 85px; width: 198px" id="imgClickAndChange" onclick="changeImage()"/>
</p>
Then you could call the javascript function when the image is clicked:
function changeImage() {
if (document.getElementById("imgClickAndChange").src == "http://www.userinterfaceicons.com/80x80/minimize.png"){
document.getElementById("imgClickAndChange").src = "http://www.userinterfaceicons.com/80x80/maximize.png";
} else {
document.getElementById("imgClickAndChange").src = "http://www.userinterfaceicons.com/80x80/minimize.png";
}
}
This code will set the image to maximize.png if the current img.src is set to minimize.png and vice versa.
For more details visit:
Change image onclick with javascript link

Or maybe
and that is prob it
<img src="path" onclick="this.src='path'">

How about this? It doesn't require so much coding.
$(".plus").click(function(){
$(this).toggleClass("minus") ;
})
.plus{
background-image: url("https://cdn0.iconfinder.com/data/icons/ie_Bright/128/plus_add_blue.png");
width:130px;
height:130px;
background-repeat:no-repeat;
}
.plus.minus{
background-image: url("https://cdn0.iconfinder.com/data/icons/ie_Bright/128/plus_add_minus.png");
width:130px;
height:130px;
background-repeat:no-repeat;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="plus">CHANGE</div>

If your images are named you can reference them through the DOM and change the source.
document["imgName"].src="../newImgSrc.jpg";
or
document.getElementById("imgName").src="../newImgSrc.jpg";

The most you could do is to trigger a background image change when hovering the LI. If you want something to happen upon clicking an LI and then staying that way, then you'll need to use some JS.
I would name the images starting with bw_ and clr_ and just use JS to swap between them.
example:
$("#images").find('img').bind("click", function() {
var src = $(this).attr("src"),
state = (src.indexOf("bw_") === 0) ? 'bw' : 'clr';
(state === 'bw') ? src = src.replace('bw_','clr_') : src = src.replace('clr_','bw_');
$(this).attr("src", src);
});
link to fiddle: http://jsfiddle.net/felcom/J2ucD/

Here, when clicking next or previous, the src attribute of an img tag is changed to the next or previous value in an array.
<div id="imageGallery">
<img id="image" src="http://adamyost.com/images/wasatch_thumb.gif" />
<div id="previous">Previous</div>
<div id="next">Next</div>
</div>
<script src="http://code.jquery.com/jquery-1.11.0.min.js"></script>
<script>
$( document ).ready(function() {
var images = [
"http://placehold.it/350x150",
"http://placehold.it/150x150",
"http://placehold.it/50x150"
];
var imageIndex = 0;
$("#previous").on("click", function(){
imageIndex = (imageIndex + images.length -1) % (images.length);
$("#image").attr('src', images[imageIndex]);
});
$("#next").on("click", function(){
imageIndex = (imageIndex+1) % (images.length);
$("#image").attr('src', images[imageIndex]);
});
$("#image").attr(images[0]);
});
</script>
I was able to implement this by modifying this answer: jQuery array with next and previous buttons to scroll through entries

If you don't want use js, I think, you can use instead of img and then use css like
a {
background: url('oldImage.png');
}
a:visited {
background: url('newImage.png');
}
EDIT: Nope. Sorry it works only for :hover

You can try something like this:
CSS
div {
width:200px;
height:200px;
background: url(img1.png) center center no-repeat;
}
.visited {
background: url(img2.png) center center no-repeat;
}
HTML
<div href="#" onclick="this.className='visited'">
<p>Content</p>
</div>
Fiddle

This script helps to change the image on click the text:
<script>
$(document).ready(function(){
$('li').click(function(){
var imgpath = $(this).attr('dir');
$('#image').html('<img src='+imgpath+'>');
});
$('.btn').click(function(){
$('#thumbs').fadeIn(500);
$('#image').animate({marginTop:'10px'},200);
$(this).hide();
$('#hide').fadeIn('slow');
});
$('#hide').click(function(){
$('#thumbs').fadeOut(500,function (){
$('#image').animate({marginTop:'50px'},200);
});
$(this).hide();
$('#show').fadeIn('slow');
});
});
</script>
<div class="sandiv">
<h1 style="text-align:center;">The Human Body Parts :</h1>
<div id="thumbs">
<div class="sanl">
<ul>
<li dir="5.png">Human-body-organ-diag-1</li>
<li dir="4.png">Human-body-organ-diag-2</li>
<li dir="3.png">Human-body-organ-diag-3</li>
<li dir="2.png">Human-body-organ-diag-4</li>
<li dir="1.png">Human-body-organ-diag-5</li>
</ul>
</div>
</div>
<div class="man">
<div id="image">
<img src="2.png" width="348" height="375"></div>
</div>
<div id="thumbs">
<div class="sanr" >
<ul>
<li dir="5.png">Human-body-organ-diag-6</li>
<li dir="4.png">Human-body-organ-diag-7</li>
<li dir="3.png">Human-body-organ-diag-8</li>
<li dir="2.png">Human-body-organ-diag-9</li>
<li dir="1.png">Human-body-organ-diag-10</li>
</ul>
</div>
</div>
<h2><a style="color:#333;" href="http://www.sanwebcorner.com/">sanwebcorner.com</a></h2>
</div>

function chkicon(num,allsize) {
var flagicon = document.getElementById("flagicon"+num).value;
if(flagicon=="plus"){
//alert("P== "+flagicon);
for (var i = 0; i < allsize; i++) {
if(document.getElementById("flagicon"+i).value !=""){
document.getElementById("flagicon"+i).value = "plus";
document.images["pic"+i].src = "../images/plus.gif";
}
}
document.images["pic"+num].src = "../images/minus.gif";
document.getElementById("flagicon"+num).value = "minus";
}else if(flagicon=="minus"){
//alert("M== "+flagicon);
document.images["pic"+num].src = "../images/plus.gif";
document.getElementById("flagicon"+num).value = "plus";
}else{
for (var i = 0; i < allsize; i++) {
if(document.getElementById("flagicon"+i).value !=""){
document.getElementById("flagicon"+i).value = "plus";
document.images["pic"+i].src = "../images/plus.gif";
}
}
}
}