javascript - Bootstrap 4 Carousel: Individual data-interval on each slide

Question

I want to set the data-interval for each slide of the carousel. Here on stackoverflow I found a JavaScript snippet for this case, but it doesn't work well. (Twitter Bootstrap Carousel slide duration) Each slide has its data-interval set inline in html with ms from 3000 to 7000 on five slides.

The real duration of the slides does not fit to my expectations and the code. Example: I set the interval to 3000 and the slide is shown around 7-8 seconds.

The js-file is written in the footer area of the site.

Here is the js code:

var t;
var start = $('#carouselExampleFade').find('.active').attr('data-interval');
t = setTimeout("$('#carouselExampleFade').carousel({interval: 1000});", start - 1000);

$('#carouselExampleFade').on('slid.bs.carousel', function() {
    clearTimeout(t);
    var duration = $(this).find('.active').attr('data-interval');

    $('#carouselExampleFade').carousel('pause');
    t = setTimeout("$('#carouselExampleFade').carousel();", duration - 1000);
})

$('.carousel-control-next').on('click', function() {
    clearTimeout(t);
});

$('.carousel-control-prev').on('click', function() {
    clearTimeout(t);
});

One part of the carousel:

<div class="row">
    <div id="carouselExampleFade" class="carousel slide carousel-fade" data-ride="carousel">
        <div class="carousel-inner">
            <div class="carousel-item active" data-interval="2000">
                <div class="carousel-caption d-none d-md-block text-left">
                    <h3>Willkommen im <br>Parkett!</h3>
                </div>
                <img class="d-block w-100" src="assets/img/animation/slide1.jpg" alt="First slide">
            </div>

Note: I have changed the lines carousel-control-next and -prev. (It was -left and -right before).

Does anyone have a good idea so solve this problem?

Answer 1

I modified the approach outlined in Bass Jobsen's answer for Bootstrap 3.x so that it works for the Bootstrap 4 carousel. IMO, this is a much cleaner approach than hooking into the jQuery events.

It overrides the interval set for the entire Carousel (this._config.interval), with intervals set on the individual carousel items (data-interval="..."):

$.fn.carousel.Constructor.prototype.cycle = function (event) {

    if (!event) {
        this._isPaused = false;
      }

      if (this._interval) {
        clearInterval(this._interval)
        this._interval = null;
      }

      if (this._config.interval && !this._isPaused) {

        var $ele = $('.carousel-item-next');
        var newInterval = $ele.data('interval') || this._config.interval;
        this._interval = setInterval(
          (document.visibilityState ? this.nextWhenVisible : this.next).bind(this),
          newInterval
        );
      }
};

https://www.codeply.com/go/sGAOcxEzV8