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Repeating Javascript Slideshow

I have a working slideshow, but at the end of the images it just stops. Is there something I can add or change to my code (below) that could have it repeat or loop continuously?
var slideIndex = 0;
showSlides();
function showSlides() {
var i;
var slides = document.getElementsByClassName("mySlides");
var dots = document.getElementsByClassName("dot");
for (i = 0; i < slides.length; i++) {
slides[i].style.display = "none";
}
slideIndex++;
if (slideIndex > slides.length) {slideIndex = 1}
for (i = 0; i < dots.length; i++) {
dots[i].className = dots[i].className.replace(" active", "");
}
slides[slideIndex-1].style.display = "block";
dots[slideIndex-1].className += " active";
setTimeout(showSlides, 2000); // Change image every 2 seconds
}

You can use setInterval instead of setTimeout
setTimeout() triggers the expression only once whilesetInterval()
keeps triggering expressionregularly after the given interval of time.
(unless you tell it to stop).
=> setInterval(showSlides, 2000)

simple javascritp Slideshow - adding controls

UPDATED:
Im doing simple lyrics slideshow I used some js slideshow and modified it.
My question is, can it be done more simple way - original code had timed autoplay etc?/
All I want is showing/hidding divs - ordered from first - listing with onclicks on prev/next divs, keys left/right or pgup/pgdn and mouse wheel roll.
CodePen
//slideshow -
//https://www.w3schools.com/howto/howto_js_slideshow.asp
var slideIndex = 1; showSlides(slideIndex);
function plusSlides(n) { showSlides(slideIndex += n); }
function currentSlide(n) { showSlides(slideIndex = n); }
function showSlides(n) {
var i;
var slides = document.getElementsByClassName("slide");
var dots = document.getElementsByClassName("dot");
if (n > slides.length) {slideIndex = 1}
if (n < 1) {slideIndex = slides.length}
for (i = 0; i < slides.length; i++) {
slides[i].style.display = "none";
}
for (i = 0; i < dots.length; i++) {
dots[i].className = dots[i].className.replace(" active", "");
}
slides[slideIndex-1].style.display = "flex";
dots[slideIndex-1].className += " active";
}

NodeList returning undefined? Function inside window.onload

So I'm currently building a carousel (code inspired from W3Schools).
function showSlides(n) {
var i;
var slides = document.getElementsByClassName("slide");
var dots = document.getElementsByClassName("dot");
if (n > slides.length) {
slideIndex = 1;
}
if (n < 1) {slideIndex = slides.length}
for (i = 0; i < slides.length; i++) {
slides[i].style.display = "none";
dots[i].className = dots[i].className.replace(" active", "");
}
slides[slideIndex-1].style.display = "block";
dots[slideIndex-1].className += " active";
changeShoeContent(slideIndex-1);
}
This code is inside a window.onload function. The slideshow works, and everything, but for some reason, whenever I try to console.log dots or slides, its returning undefined. The slideshow works, which means that the for loop is able to change the display and class names of the slides and dots nodeList. Am I doing something wrong here, or am I missing something?

pause / play SlideShow (setInterval) in Javascript

to start things of I want to mention that I am very new at this and probably very bad and I have tried for weeks now, searched answers and so on and just couldn't implement something proper in my code. I want to simply pause / resume a slide animation. I managed to make most of it work, but the problem is the setInterval. mine is set to 10s. I have a fading-in-out animation that lasts also 10 secs. If i pause lets say after 5 secs and then resume, the animation will have 10 extra seconds adding up to 15, after which it will change the slide abruptly and I want a smooth transition.
What I could think of is to save the elapsed time from the interval at the moment of pausing and then subtract that value from the total time of the interval and set it for the remaining part. Problem is i don't know how to put that into code. :/
var slideIndex = 1;
var myIndex = 0;
var myVar;
var playing = true;
var pauseButton = document.getElementById("pause");
var y = document.getElementsByClassName("mySlides");
var k;
var div = document.getElementsByClassName("stuff");
var globaltime = 10000;
var slideInterval = setInterval(carousel, globaltime);
var milisec;
function plusDivs(n) {
showDivs(slideIndex += n);
}
function currentDiv(n) {
showDivs(slideIndex = n);
}
function showDivs(n) {
var i;
var x = document.getElementsByClassName("mySlides");
var dots = document.getElementsByClassName("demo");
if (n > x.length) {slideIndex = 1}
if (n < 1) {slideIndex = x.length}
for (i = 0; i < x.length; i++) {
x[i].style.display = "none";
}
for (i = 0; i < dots.length; i++) {
dots[i].className = dots[i].className.replace(" white", "");
}
x[slideIndex-1].style.display = "block";
dots[slideIndex-1].className += " white";
}
function carousel() {
var i;
var x = document.getElementsByClassName("mySlides");
var dots = document.getElementsByClassName("demo");
for (i = 0; i < x.length; i++) {
x[i].style.display = "none";
}
myIndex++;
if (myIndex > x.length) {myIndex = 1}
for (i = 0; i < dots.length; i++) {
dots[i].className = dots[i].className.replace(" white", "");
}
x[myIndex-1].style.display = "block";
dots[myIndex-1].className += " white";
}
function pauseSlideshow(){
pauseButton.innerHTML = '►';
playing = false;
t = slideInterval;
clearInterval(slideInterval);
for (k = 0; k < div.length; k++) {
div[k].className = div[k].className.replace(" running", " paused");
}
}
function playSlideshow(){
pauseButton.innerHTML = '❙❙';
playing = true;
slideInterval = setInterval(carousel, globaltime);
for (k = 0; k < div.length; k++) {
div[k].className = div[k].className.replace(" paused", " running");
}
}
function stop(){
if(playing){
pauseSlideshow();
}
else {
playSlideshow();
}
}
carousel();
timer();
showDivs(slideIndex);
Thank you very much in advance for your time, patience and understanding.

Stop Slide Show on mouse over in Javascript

I am using following java-script for a slide show, now I like to pause the loop on mouse-over event on the element "dot", my expertise in java is zero, please help.
<script>
var slideIndex = 0;
showSlides();
function showSlides() {
var i;
var slides = document.getElementsByClassName("mySlides");
var dots = document.getElementsByClassName("dot");
for (i = 0; i < slides.length; i++) {
slides[i].style.display = "none";
}
slideIndex++;
if (slideIndex > slides.length) { slideIndex = 1 }
for (i = 0; i < dots.length; i++) {
dots[i].className = dots[i].className.replace("active","");
}
slides[slideIndex - 1].style.display = "block";
dots[slideIndex - 1].className += " active";
setTimeout(showSlides, 5000); // Change text every 5 seconds
}
</script>

A few things. Firstly, I would suggest using setInterval() instead. This allows you to easily stop the timer outside of the function. The syntax is identical to setTimeout(). setInterval() is very similar to setTimeout(), except it will continue to execute the function (the first parameter) until you call clearInterval().
Note that setInterval() (and setTimeout()) returns a value, which can be used for clearInterval() and clearTimeout(), respectively.
Changing your code to utilize setInterval should be fairly straightforward. Given what you have posted above, it might look something like this:
<script>
var slideIndex = 0;
showSlides();
function showSlides() {
var i;
var slides = document.getElementsByClassName("mySlides");
var dots = document.getElementsByClassName("dot");
for (i = 0; i < slides.length; i++) {
slides[i].style.display = "none";
}
slideIndex++;
if (slideIndex > slides.length) { slideIndex = 1 }
for (i = 0; i < dots.length; i++) {
dots[i].className = dots[i].className.replace("active","");
}
slides[slideIndex - 1].style.display = "block";
dots[slideIndex - 1].className += " active";
}
var interval = setInterval(showSlides, 5000); // Change text every 5 seconds
Note that I save interval as a variable that can be used later to stop the timer.
Once you have made this change, the solution to your main question becomes much easier. You can set up event handlers by adding the following:
function pauseSlides(event)
{
clearInterval(interval); // Clear the interval we set earlier
}
function resumeSlides(event)
{
interval = setInterval(showSlides, 5000);
}
// Set up event listeners for the dots
var dots = document.getElementsByClassName("dot");
for (i = 0; i < dots.length; i++) {
dots[i].onmouseover = pauseSlides;
dots[i].onmouseout = resumeSlides;
}
The entirety of your code, given the above, may now look something like this:
<script>
var slideIndex = 0;
showSlides();
function showSlides() {
var i;
var slides = document.getElementsByClassName("mySlides");
var dots = document.getElementsByClassName("dot");
for (i = 0; i < slides.length; i++) {
slides[i].style.display = "none";
}
slideIndex++;
if (slideIndex > slides.length) { slideIndex = 1 }
for (i = 0; i < dots.length; i++) {
dots[i].className = dots[i].className.replace("active","");
}
slides[slideIndex - 1].style.display = "block";
dots[slideIndex - 1].className += " active";
}
var interval = setInterval(showSlides, 5000); // Change text every 5 seconds
// Set up event listeners for the dots
var dots = document.getElementsByClassName("dot");
for (i = 0; i < dots.length; i++) {
dots[i].onmouseover = pauseSlides;
dots[i].onmouseout = resumeSlides;
}
function pauseSlides()
{
clearInterval(interval); // Clear the interval we set earlier
}
function resumeSlides()
{
interval = setInterval(showSlides, 5000);
}
</script>
Additionally, for reference:
setInterval() reference: https://www.w3schools.com/jsref/met_win_setinterval.asp
Events in JavaScript: https://www.w3schools.com/jsref/dom_obj_event.asp

Wonderful Aaron, much appreciated response. I just checked the code and its working perfectly.
Can we modify this code further and on-mouse over event we can go to specific slide? i mean by using the same "dot" element? The dots are representing different slides, so I want if a user trigger mouse over event on any dot, the slide display benith that specific dot element.