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javascripthtmlslideshow

Switching Between Two Slideshows with Javascript


I have a web page with a slideshow. The slideshow has three pictures. I would like to have a button on the page which enables users to switch between this slideshow and another with five different pictures. How would I program this button with JavaScript and where would I add the second slideshow in the HTML?

Current HTML:

<div class="slideshow-container">
  <div class="mySlides fade">
    <div class="numbertext">1 / 3</div>
    <img src="img1.jpg" style="width:100%">
    <div class="text">Caption Text</div>
  </div>

  <div class="mySlides fade">
    <div class="numbertext">2 / 3</div>
    <img src="img2.jpg" style="width:100%">
    <div class="text">Caption Two</div>
  </div>

  <div class="mySlides fade">
    <div class="numbertext">3 / 3</div>
    <img src="img3.jpg" style="width:100%">
    <div class="text">Caption Three</div>
  </div>

  <a class="prev" onclick="plusSlides(-1)">&#10094;</a>
  <a class="next" onclick="plusSlides(1)">&#10095;</a>
</div>
<br>

<div style="text-align:center">
  <span class="dot" onclick="currentSlide(1)"></span>
  <span class="dot" onclick="currentSlide(2)"></span>
  <span class="dot" onclick="currentSlide(3)"></span>
</div>
<button>Switch Slideshow</button>

Current CSS:

 /* Slideshow container */
.slideshow-container {
  max-width: 1000px;
  position: relative;
  margin: auto;
}

/* Next & previous buttons */
.prev, .next {
  cursor: pointer;
  position: absolute;
  top: 50%;
  width: auto;
  margin-top: -22px;
  padding: 16px;
  color: white;
  font-weight: bold;
  font-size: 18px;
  transition: 0.6s ease;
  border-radius: 0 3px 3px 0;
}

/* Position the "next button" to the right */
.next {
  right: 0;
  border-radius: 3px 0 0 3px;
}

/* On hover, add a black background color with a little bit see-through */
.prev:hover, .next:hover {
  background-color: rgba(0,0,0,0.8);
}

/* Caption text */
.text {
  color: #f2f2f2;
  font-size: 15px;
  padding: 8px 12px;
  position: absolute;
  bottom: 8px;
  width: 100%;
  text-align: center;
}

/* Number text (1/3 etc) */
.numbertext {
  color: #f2f2f2;
  font-size: 12px;
  padding: 8px 12px;
  position: absolute;
  top: 0;
}

/* The dots/bullets/indicators */
.dot {
  cursor:pointer;
  height: 13px;
  width: 13px;
  margin: 0 2px;
  background-color: #bbb;
  border-radius: 50%;
  display: inline-block;
  transition: background-color 0.6s ease;
}

.active, .dot:hover {
  background-color: #717171;
}

/* Fading animation */
.fade {
  -webkit-animation-name: fade;
  -webkit-animation-duration: 1.5s;
  animation-name: fade;
  animation-duration: 1.5s;
}

@-webkit-keyframes fade {
  from {opacity: .4}
  to {opacity: 1}
}

@keyframes fade {
  from {opacity: .4}
  to {opacity: 1}
}

Current JavaScript:

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("mySlides");
  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 = "block";
  dots[slideIndex-1].className += " active";
}

Many thanks in advance!


Solution

  • Well, you need to first be able to create your slideshow dynamically. Only then will you be able to swap in-and-out different slides. I tried not to refactor your existing code. Also, I did not use jQuery (which I would use personally). Just generate the markup for each slide and set it on the slides div. I had to create an inner div so that the buttons do not get overridden.

    var slideshowIndex = 1;
    var slideIndex = 1;
    var slideshows = [
      [
        'http://placehold.it/500x300/f00/0ff?text=Foo',
        'http://placehold.it/500x300/0f0/f0f?text=Bar',
        'http://placehold.it/500x300/00f/ff0?text=Baz'
      ], [
        'http://placehold.it/500x300/f70/07f?text=Fizz',
        'http://placehold.it/500x300/0f7/f07?text=Buzz',
        'http://placehold.it/500x300/70f/7f0?text=Bang'
      ]
    ];
    var buttonTextArr = [ 'Show Images', 'Show Pages' ];
    function createSlides(slides) {
      return slides.map(function(slide, index) {
        return [
          '<div class="mySlides fade">',
          '<div class="numbertext">' + (index + 1) + ' / ' + slides.length + '</div>',
          '<img src="' + slide + '">',
          '<div class="text">Caption #' + (index + 1) + '</div>',
          '</div>'
        ].join('');
      }).join('');
    }
    function createDots(slides) {
      return slides.map(function(slide, index) {
        return '<span class="dot" onclick="currentSlide(' + (index + 1) + ')"></span>'
      }).join('');
    }
    function loadSlideshow(slides) {
      document.getElementsByClassName('slideshow-slides')[0].innerHTML = createSlides(slides);
      document.getElementsByClassName('dots')[0].innerHTML = createDots(slides);
    }
    function loadNextSlideshow() {
      slideshowIndex = (slideshowIndex + 1) % 2;
      loadSlideshow(slideshows[slideshowIndex]);
      slideIndex = 1; // Reset index
      showSlides(slideIndex);
      document.getElementsByClassName('switch')[0].innerHTML = buttonTextArr[slideshowIndex];
    }
    
    loadNextSlideshow(); // Load the slideshow
    
    function plusSlides(n) {
      showSlides(slideIndex += n);
    }
    function currentSlide(n) {
      showSlides(slideIndex = n);
    }
    function showSlides(n) {
      var i;
      var slides = document.getElementsByClassName("mySlides");
      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 = "block";
      dots[slideIndex - 1].className += " active";
    }
    /* Slideshow container */
    .slideshow-container {
      max-width: 1000px;
      position: relative;
      margin: auto;
    }
    
    /* Next & previous buttons */
    .prev, .next {
      cursor: pointer;
      position: absolute;
      top: 50%;
      width: auto;
      margin-top: -22px;
      padding: 16px;
      color: white;
      font-weight: bold;
      font-size: 18px;
      transition: 0.6s ease;
      border-radius: 0 3px 3px 0;
      text-shadow: 0.05em 0.05em 0.25em #000;
    }
    
    /* Position the "next button" to the right */
    .next {
      right: 0;
      border-radius: 3px 0 0 3px;
    }
    
    /* On hover, add a black background color with a little bit see-through */
    .prev:hover, .next:hover {
      background-color: rgba(0, 0, 0, 0.8);
    }
    
    /* Caption text */
    .text {
      color: #f2f2f2;
      font-size: 15px;
      padding: 8px 12px;
      position: absolute;
      bottom: 8px;
      width: 100%;
      text-align: center;
    }
    
    /* Number text (1/3 etc) */
    .numbertext {
      color: #f2f2f2;
      font-size: 12px;
      padding: 8px 12px;
      position: absolute;
      top: 0;
    }
    
    /* The dots/bullets/indicators */
    .dot {
      cursor: pointer;
      height: 13px;
      width: 13px;
      margin: 0 2px;
      background-color: #bbb;
      border-radius: 50%;
      display: inline-block;
      transition: background-color 0.6s ease;
    }
    .active, .dot:hover {
      background-color: #717171;
    }
    
    /* Fading animation */
    .fade {
      -webkit-animation-name: fade;
      -webkit-animation-duration: 1.5s;
      animation-name: fade;
      animation-duration: 1.5s;
    }
    
    @-webkit-keyframes fade {
      from { opacity: 0.4 }
      to   { opacity: 1 }
    }
    @keyframes fade {
      from { opacity: 0.4 }
      to   { opacity: 1 }
    }
    <div class="slideshow-container">
      <div class="slideshow-slides"></div>
      <a class="prev" onClick="plusSlides(-1)">&#10094;</a>
      <a class="next" onClick="plusSlides(1)">&#10095;</a>
    </div>
    <br />
    <div class="dots" style="text-align:center"></div>
    <button class="switch" onClick="loadNextSlideshow()">Switch Slideshow</button>