问题
This slide needs clicking on the "Next" button to play.
What can I do to make the slide show auto-play base on this function?
Here is my source.
<script>
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";
}
</script>
回答1:
You can achieve this with setInterval function. Try my code
<!DOCTYPE html>
<html>
<title>W3.CSS</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="http://www.w3schools.com/lib/w3.css">
<style>
.mySlides {
display: none
}
.w3-left,
.w3-right,
.w3-badge {
cursor: pointer
}
.w3-badge {
height: 13px;
width: 13px;
padding: 0
}
</style>
<body>
<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="http://www.w3schools.com/w3css/img_nature_wide.jpg" style="width:100%">
<img class="mySlides" src="http://www.w3schools.com/w3css/img_fjords_wide.jpg" style="width:100%">
<img class="mySlides" src="http://www.w3schools.com/w3css/img_mountains_wide.jpg" style="width:100%">
<div class="w3-center w3-section w3-large w3-text-white w3-display-bottommiddle" style="width:100%">
<div class="w3-left w3-padding-left w3-hover-text-khaki" onclick="plusDivs(-1)">❮</div>
<div class="w3-right w3-padding-right w3-hover-text-khaki" onclick="plusDivs(1)">❯</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>
<script>
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";
}
setInterval(function () {
plusDivs(1);
}, 1000);
</script>
</body>
</html>
来源:https://stackoverflow.com/questions/41234943/how-to-make-slideshow-auto-play