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I want to make this slideshow from w3.css library to slideshow automatically every 4-5 seconds. Can also be found at w3schools editor.

More documentation of w3.css slideshows can be found here

I need to somehow add this code to make the images slideshow automatically but keep the bullets background and make the arrows work:

var slideIndex = 0;
carousel();
function carousel() {
    var i;
    var x = document.getElementsByClassName("mySlides");
    for (i = 0; i < x.length; i++) {
      x[i].style.display = "none"; 
    }
    slideIndex++;
    if (slideIndex > x.length) {slideIndex = 1} 
    x[slideIndex-1].style.display = "block"; 
    setTimeout(carousel, 2000); // Change image every 2 seconds
}

Here is the complete code:

var slideIndex = 1;
showDivs(slideIndex);

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(" w3-white", "");
  }
  x[slideIndex-1].style.display = "block";  
  dots[slideIndex-1].className += " w3-white";
}
.mySlides {display:none}
.w3-left, .w3-right, .w3-badge {cursor:pointer}
.w3-badge {height:13px;width:13px;padding:0}
<link rel="stylesheet" href="https://www.w3schools.com/w3css/4/w3.css">

<div class="w3-container">
  <h2>Slideshow Indicators</h2>
  <p>An example of using buttons to indicate how many slides there are in the slideshow, and which slide the user is currently viewing.</p>
</div>

<div class="w3-content w3-display-container" style="max-width:800px">
  <img class="mySlides" src="https://cdn-s3.si.com/styles/marquee_large_2x/s3/images/trump-5.jpg" style="width:100%">
  <img class="mySlides" src="https://i.ytimg.com/vi/VpevTNRK-_M/maxresdefault.jpg" style="width:100%">
  <img class="mySlides" src="https://img00.deviantart.net/a73e/i/2015/261/4/3/the_magic_world_by_chibionpu-d4ol7wm.jpg" style="width:100%">
  <div class="w3-center w3-container w3-section w3-large w3-text-white w3-display-bottommiddle" style="width:100%">
    <div class="w3-left w3-hover-text-khaki" onclick="plusDivs(-1)">&#10094;</div>
    <div class="w3-right w3-hover-text-khaki" onclick="plusDivs(1)">&#10095;</div>
    <span class="w3-badge demo w3-border w3-transparent w3-hover-white" onclick="currentDiv(1)"></span>
    <span class="w3-badge demo w3-border w3-transparent w3-hover-white" onclick="currentDiv(2)"></span>
    <span class="w3-badge demo w3-border w3-transparent w3-hover-white" onclick="currentDiv(3)"></span>
  </div>
</div>
  • What's the reason that you want to use this slider? It is not really accessible and I would be surprised if it would work well on mobile devices. Why not use a slider like http://kenwheeler.github.io/slick/ (or just search for javascript slider) which is tested, robust and future proof and has everything you need out of the box? – cloned Sep 12 '17 at 11:42
  • I was looking for a fast and simple slider that will not slow down the website. this code only uses one css library it is quite light –  Sep 12 '17 at 11:44
  • 1
    one slider won't really slow down your website. You are doing more harm than good when you use the one from w3schools. If you are using bootstrap, it comes with a slider built in https://getbootstrap.com/docs/4.0/components/carousel/ . Many pages use bootstrap and it doesn't slow pages down. Javascript isn't as slow as it was 20 years ago. – cloned Sep 12 '17 at 12:43
  • 1
    If it's production, not practicing, always go with battle tested solutions that are robust and perform well over multiple browsers / devices / OSs. That will save you A LOT of work. – DanteTheSmith Sep 12 '17 at 12:46
  • ok then I will go for the bootrap carousel, which I also tried and works pretty well. Thanks guys –  Sep 12 '17 at 12:47

1 Answers1

2
setInterval(function(){
    slideIndex++;
    currentDiv(slideIndex);
}, 2000);

Add this to your code example at the end

Jessie Koffi
  • 174
  • 7
  • nice but when you click on the button to change image, the timer (2 seconds) , has to reset –  Sep 12 '17 at 13:00
  • right. see this: https://stackoverflow.com/questions/8126466/javascript-reset-setinterval-back-to-0 – Jessie Koffi Sep 13 '17 at 21:05