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Background image change from array of images on button click in JavaScript

I want to change the background image of my app on button click. I put the images in an array and selecting the background image randomly. Below is the code.
const background = [
"image/2.png",
"image/4.png",
"image/9.png",
"image/14.png",
"image/12.png",
"image/17.png",
];
function changeColor() {
const getimage = `${
background[Math.floor(Math.random() * background.length)]
}`;
document.querySelector("body").style.backgroundImage = 'url("getimage")';
console.log(getimage);
}
The Console log shows that 'on button click' the getimage variable is changing randomly. But in the browser, the background is not changing! Not getting what am I missing?

When you set the style you are setting the url to getimage as a string instead of the element. To fix your problem, you just need to put it as the element, either as
document.querySelector("body").style.backgroundImage = `url("${getimage}")`;
// uses `` to include a variable using ${}
or:
document.querySelector("body").style.backgroundImage = 'url("' + getimage + '")'; // adds the variable in the middle of the string

Try interpolate getimage
document.querySelector("body").style.background = `url(${getimage})`;

Change class on multiple img in array

This is my first post here, I always found solutions on this page, so thank you for that.
I have a problem with .removeClass and .addClass in my last program.
I load multiple pictures into array Frames and I want change all (previous-image) to (current-image) in frames[0]. Here is my code, it is change class only on second image. Here is code:
function loadImage() {
// Creates a new <li>
var li = document.createElement("li");
// Generates the image file name using the incremented "loadedImages" variable
var imageName = "graphics/img/Dodge_Viper_SRT10_2010_360_720_50-" + (loadedImages + 1) + ".jpg";
var imageName1 = "graphics/img/Dodge_Viper_SRT10_2010_360_720_50-" + (loadedImages + 1) + ".jpg";
/*
Creates a new <img> and sets its src attribute to point to the file name we generated.
It also hides the image by applying the "previous-image" CSS class to it.
The image then is added to the <li>.
*/
var image = $('<img>').attr('src', imageName).addClass("previous-image").appendTo(li) && $('<img>').attr('src', imageName1).addClass("previous-image light-image").appendTo(li);
// We add the newly added image object (returned by jQuery) to the "frames" array.
frames.push(image);
// We add the <li> to the <ol>
$images.append(li);
/*
Adds the "load" event handler to the new image.
When the event triggers it calls the "imageLoaded" function.
*/
$(image).load(function() {
imageLoaded();
});
};
function imageLoaded() {
// Increments the value of the "loadedImages" variable
loadedImages++;
// Updates the preloader percentage text
$("#spinner span").text(Math.floor(loadedImages / totalFrames * 100) + "%");
// Checks if the currently loaded image is the last one in the sequence...
if (loadedImages == totalFrames) {
// ...if so, it makes the first image in the sequence to be visible by removing the "previous-image" class and applying the "current-image" on it
frames[0].removeClass("previous-image").addClass("current-image");
/*
Displays the image slider by using the jQuery "fadeOut" animation and its complete event handler.
When the preloader is completely faded, it stops the preloader rendering and calls the "showThreesixty" function to display the images.
*/
$("#spinner").fadeOut("slow", function() {
spinner.hide();
showThreesixty();
});
} else {
// ...if not, Loads the next image in the sequence
loadImage();
}
};
This is, how it looks in browser:
<ol><li><img src="graphics/img/Dodge_Viper_SRT10_2010_360_720_50-1.jpg" class="previous-image"><img src="graphics/img/Dodge_Viper_SRT10_2010_360_720_50-1.jpg" class="light-image current-image"></li></ol>
This is, what I want:
<ol><li><img src="graphics/img/Dodge_Viper_SRT10_2010_360_720_50-1.jpg" class="current-image"><img src="graphics/img/Dodge_Viper_SRT10_2010_360_720_50-1.jpg" class="light-image current-image"></li></ol>
When I change this
var image = $('<img>').attr('src', imageName).addClass("previous-image").appendTo(li) && $('<img>').attr('src', imageName1).addClass("previous-image light-image").appendTo(li);
to this
var image = $('<img>').attr('src', imageName1).addClass("previous-image light-image").appendTo(li) && $('<img>').attr('src', imageName).addClass("previous-image").appendTo(li);
it still change only second img. Any help?

var image = $('<img>').attr('src', imageName).addClass("previous-image").appendTo(li) && $('<img>').attr('src', imageName1).addClass("previous-image light-image").appendTo(li);
is not doing what you think it is. It's only using the second element you declare. They both get appended to the page (because the appendTo method runs), but && is a logical operator, it's not used for concatenation, so the variable "image" only contains the second image you declared.
This will work instead:
var image = $('<img>', { "src": imageName, "class": "previous-image" });
image = image.add($('<img>', { "src": imageName1, "class": "previous-image light-image" }));
image.appendTo(li);

If you are just trying to replace all the previous-image classes with current image then you can do this:
$('img.previous-image').each(function(){
$(this).addClass("current-image").removeClass("previous-image");
});

How can we make Image Carousel with background Image Property

I'm making an image carousel i'm bounded to use background-image property instead of using
<img src="Image">
tag. my carousel is working if I use img tag . But its not working when I use background-image property, how can I modify my code with background-image property.
see my fiddle :https://jsfiddle.net/korLasen/ and update it please thanks :)
or you can see code here
(function(){
var image = $('#imageSlider');
var imageSet = ['http://www.exposureguide.com/images/top-ten-tips/top-ten-photography-tips-1e.jpg','http://images.clipartpanda.com/cliparts-images-aTqyrB8TM.png'];
var index = 0;
function imageSliderSet(){
image.setAttribute('data-background', imageSet[index]);
index++;
if(index >= imageSet.length){
index = 0;
}
}
setInterval = (imageSliderSet, 2000);
})();

This is quite a strange question... however, I am not one to judge :)
Here is a jsfiddle based on your example. I ended up using jquery for this. I hope this is somewhere near what you were looking for!
This is based on changing every two seconds. To extend that, you can change line 18 in the jquery. Here is the jquery:
$( document ).ready(function(){
var image = $('#imageSlider');
var imageSet = ['http://www.exposureguide.com/images/top-ten-tips/top-ten-photography-tips-1e.jpg','http://images.clipartpanda.com/cliparts-images-aTqyrB8TM.png'];
var index = 0;
window.setInterval(function(){
image.css('background-image', "url('" + imageSet[index] + "')");
index++;
if(index >= imageSet.length){
index = 0;
}
//here you can adjust the time interval for each photo
}, 2000);
});

building a Jquery Tool slider like yahoo.com slider details

Hi im trying to achieve a "news slider" like the one you can see in yahoo.com... I almost have the 100% of the code.. (if you want to compare them here is my code http://jsfiddle.net/PcAwU/1/)
what is missing in my code , (forget about design) is that , In my slider you have to clic on each item, i tried to replace Onclick for Hover on the javascript, it worked, but the fisrt image on the gallery stop working, so when you just open the slider, you see a missing image.
Other point.. also very important, in yahoo.com after "x seconds" the slider goes to the next item, and so on ... all the Thumnails are gruped 4 by for 4, (in mine 5 by 5, thats ok) ... after pass all the 4 items, it go to the next bloc..
HOW CAN I ACHIEVE THAT!!. I really looked into the API, everything, really im lost, i hope someone can help me. cause im really lost in here.
Thanks
Here is the script
$(function() {
var root = $(".scrollable").scrollable({circular: false}).autoscroll({ autoplay: true });
$(".items img").click(function() {
// see if same thumb is being clicked
if ($(this).hasClass("active")) { return; }
// calclulate large image's URL based on the thumbnail URL (flickr specific)
var url = $(this).attr("src").replace("_t", "");
// get handle to element that wraps the image and make it semi-transparent
var wrap = $("#image_wrap").fadeTo("medium", 0.5);
// the large image from www.flickr.com
var img = new Image();
// call this function after it's loaded
img.onload = function() {
// make wrapper fully visible
wrap.fadeTo("fast", 1);
// change the image
wrap.find("img").attr("src", url);
};
// begin loading the image from www.flickr.com
img.src = url;
// activate item
$(".items img").removeClass("active");
$(this).addClass("active");
// when page loads simulate a "click" on the first image
}).filter(":first").click();
// provide scrollable API for the action buttons
window.api = root.data("scrollable");
});
function toggle(el){
if(el.className!="play")
{
el.className="play";
el.src='images/play.png';
api.pause();
}
else if(el.className=="play")
{
el.className="pause";
el.src='images/pause.png';
api.play();
}
return false;
}

To fix the hover problem you need to make some quick changes: Change the click to a on(..) similar to just hover(..) just the new standard.
$(".items img").on("hover",function() {
....
Then You need to update the bottom click event to mouse over to simulate a hover effect. Trigger is a comman function to use to trigger some event.
}).filter(":first").trigger("mouseover");
jSFiddle: http://jsfiddle.net/PcAwU/2/
Now to have a play feature, you need a counter/ and a set interval like so:
var count = 1;
setInterval(function(){
count++; // add to the counter
if($(".items img").eq(count).length != 0){ // eq(.. select by index [0],[1]..
$(".items img").eq(count).trigger("mouseover");
} else count = 0; //reset counter
},1000);
This will go show new images every 1 second (1000 = 1sec), you can change this and manipulate it to your liking.
jSFiddle: http://jsfiddle.net/PcAwU/3/
If you want to hover the active image, you need to do so with the css() or the addClass() functions. But You have done this already, All we have to do is a simple css change:
.scrollable .active {
....
border-bottom:3px solid skyblue;
Here is the new update jSFilde: http://jsfiddle.net/PcAwU/4/

Increment Number in Image Source On Click

Basically I want to create next and previous buttons for a JQuery Image Gallery I'm working on. Each button has an id of "next" and "prev" respectively. What I'm trying to do is change a number that is in the source of the main image in the gallery (which has an id of mainImg). I have been able to target the number within the source of each image but I can't seem to increment it correctly and then replace the current image's source number with the new, incremented number. I tried using a while loop, for loop, and if statement but none of them worked correctly. To see the gallery that I have so far, I have it uploaded here: http://tiger.towson.edu/~abarso2/463/projecta/index.html If you go into my script.js file you'll see a block commented out at the bottom. That is the function I have so far that targets the number within the image's source and parses it to an integer. Thanks in advance for any help.
Here's what I have currently:
(function(){
var mainImg = $('#mainImg').attr('src');
var mainImgStr = mainImg.charAt(mainImg.length - 5);
var mainImgNum = parseInt(mainImgStr);
$('#next').click(function(){
});
}());

This should solve your problem
$(function(){
var mainImg = $('#mainImg');
var slidshow = $('#slideShow');
$('#next').click(function(){
var src = mainImg.attr('src').replace('thumb','shot');
var next = $('img[src="' + src +'"]', slidshow).next();
if(next.length){
mainImg.attr('src',next.attr('src').replace('thumb','shot'));
}
});
$('#prev').click(function(){
var src = mainImg.attr('src').replace('thumb','shot');
var prev = $('img[src="' + src +'"]', slidshow).prev();
if(prev.length){
mainImg.attr('src',prev.attr('src').replace('thumb','shot'));
}
});
});

Here is the revised code. The regexp will work better. The user can click the next button multiple times but no image will be skipped as the main image will only go to the next if and when the next image is loaded. So if you click next quickly 5 times only the next image will show (not skipping 4 images).
(function(){
// replace all non digit characters from src
// only the last set of numbers so www.123.com/image7.jpg
// will give us 7
function getNumber(src){
return parseInt(src.replace(/[\d]+(?=[\/])/g,"")
.replace(/[^\d]/g,""),10);
}
// replaces last number of a source with the number provided
// www.123.com/imgage7.jpg will be www.123.com/image8.jpg
// if number 8 is given
function setNumber(src,num){
return src.replace(/[\d]+(?![\d])/g,num);
}
var $mainImg = $('#mainImg');
$('#next').click(function(){
var src= $mainImg.attr('src'),
mainImgNum = getNumber(src);
var $img=$(document.createElement("img"));
$img.data("checkNext",false);
$img.on("load",function(){
// image exsist, load it as main image src
if($img.data("checkNext")===true){
$img.remove();
}else{
$mainImg.attr('src',$img.attr('src'));
$("#prev").show(1000);
$img.data("checkNext",true);
$img.attr('src',setNumber($img.attr('src'),
new String(mainImgNum+2));
});
$img.on("error",function(){
if($img.data("checkNext")===true){
$("#next").hide(1000);
}
// clean up
$img.remove();
});
$img.attr('src',setNumber(src,new String(mainImgNum+1)));
});
}());