I've been following a slideshow tutorial on w3schools to learn how to create my own.
This is the link to the tutorial's code. What I am referring to is this code however.
<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, 2000); // Change image every
2 seconds
}
</script>
I wanted to make multiple slideshows for a single page so I made it so this section of the code would take a parameter and then I could just insert my list of images. But when I changed the code to this...
var images = document.getElementsByClassName("mySlides");
var imageNum = document.getElementsByClassName("dot");
showSlides(images, imageNum);
function showSlides(slides, dots) {
var i;
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);
}
Complete code available via this link.
It gives me the error property of length undefined, even though .length can be used on a HTML Collection.
Why does it seem that this function cannot accept a HTML Collection as a parameter?
Edit: After looking at feedback and noticing that I made it harder for people to help me, I made a codesandbox link with my issue. I included the solution as a comment, so people can see before and after. I also included the entire function above.
Thank you for your feedback so I can make questions more clear and sorry about the trouble!
It's because of that line at the end of the function
setTimeout(showSlides, 2000); // Change image every 2 seconds
it call showSlides without any arguments
To add argument to call you can do :
setTimeout(() => { showSlides(slides, dots) }, 2000);
// call from an anonymous function
// or
setTimeout(showSlides, 2000, slides, dots);
// use additional params of setTimeout
Here's the doc for setTimeout
Related
I am very new in JavaScript. I have multiple sliders on a single screen. You can see by going on this link: http://iliachtida.sportpolis.gr/play-unit/#
I am running a slider when click on the current product, but my slider behavior goes wrong when I click on the arrow.
When I click on the arrow only one product image is displayed, all the other images are not displayed.
I want to run different sliders for different products. Suppose I have four products on this screen and every product has four images. I want to run first product images on first product arrow click, second product images on second product arrow click, etc. I hope you understand.
I have tried many code, but it does not work for me.
This is my code:
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("size-full");
var dots = document.getElementsByClassName("dot");
if (n > slides.length) {slideIndex = 1}
if (n < 1) {slideIndex = slides.length}
for (i = 0; i < slides.length; i++)
{
//alret(slideIndex);
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 = "block";
//dots[slideIndex-1].className += " active";
}
My page wont display it keeps saying Jslint Error on my external javascript code, but if i include the javascript in head section it will display properly. Am really new to coding so please i don't know what next to look out for.
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
}
I have my JavaScript file located in a different folder, so right now it can't find the class that it's looking for. I'd like it to know the path of the class while being in a separate folder.
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
}
Your code has nothing whatsoever to do with path
Perhaps you load the script in the head before the slideshow html exists.
Try
var slideIndex = 0;
window.addEventListener("load",showSlides);
Im trying to make a slideshow of images that changes every 10 seconds but has a button at the bottom where if you clicked on the dot it will take you back to that image. The problem is when I click the of the buttons it speeds the timer up. how do i stop this, so that when i click on the button it resets the timer?
function showSlides() {
var nextSlide = false
var i;
var slides = document.getElementsByClassName("mySlides");
var dots = document.getElementsByClassName("dot");
for (i = 0; i < slides.length; i++) {
slides[i].style.display = "none";
}
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, 10000, slideIndex++); // Change image every 10 seconds
}
thanks to a comment by Teemu. who showed me how to do it, i applyed it to the code and it works
function timer() {
this.STimer = setTimeout(showSlides, 10000, slideIndex++);
}
function cancelTimer(){
clearTimeout(this.STimer);
}
function currentDiv(n) {
cancelTimer();
showSlides(slideIndex = n);
}
function showSlides() {
var nextSlide = false
var i;
var slides = document.getElementsByClassName("mySlides");
var dots = document.getElementsByClassName("dot");
for (i = 0; i < slides.length; i++) {
slides[i].style.display = "none";
}
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";
timer();
}
Hi I have a slideshow javascript running on my website but it doesn't seem to be working properly when I change the images back and forth and the automaticity doesn't show image 6. Could someone please help me write it up because I have been trying over a month and reached nowhere.
https://wbd-ownwork-13--15nalaas.repl.co/
<script>
var slideIndex = 1;
showSlides(slideIndex);
// Next/previous controls
function plusSlides(n) {
showSlides(slideIndex += n);
}
// Thumbnail image controls
function currentSlide(n) {
showSlides(slideIndex = n);
}
function showSlides(n) {
var i;
var slides = document.getElementsByClassName("mySlides");
var dots = document.getElementsByClassName("demo");
var captionText = document.getElementById("caption");
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 = "block";
dots[slideIndex-1].className += " active";
captionText.innerHTML = dots[slideIndex-1].alt;
}
var slideIndex = 0;
showSlides();
function showSlides() {
var i;
var slides = document.getElementsByClassName("mySlides");
for (i = 0; i < slides.length; i++) {
slides[i].style.display = "none";
}
slideIndex++;
if (slideIndex > slides.length) {slideIndex = 2}
slides[slideIndex-2].style.display = "block";
setTimeout(showSlides, 4000); // Change image every 4 seconds
}
</script>
First of all you need not to add the custom controls for changing the slides because the slide show is more than enough.
And secondly you need to change the entire script to the given script only then it is going to work because rest of your script is messing with the slideshow.
Change the entire script from line 94 to line 125 in your HTML to this -
<script>
var slideIndex = 0;
showSlides();
function showSlides(){
var slides = document.querySelectorAll('.mySlides');
for(var i = 0; i < slides.length; i++){
slides[i].style.display = "none";
}
slides[slideIndex].style.display = "block";
slideIndex++;
if(slideIndex > slides.length - 1){slideIndex = 0}
loop();
}
function loop(){
setTimeout(showSlides, 1000);
}
</script>
If still you have a problem the please ask again.