Wsrtjtyk

I'm trying to create previous / next buttons on each accordion body.

I can't figure out a way to collapse / expand a certain section. I tried removing the class in from the accordion-body but that does not seem to collapse.

        $(".accordion-body").each(function(){

            if($(this).hasClass("in")) {

                $(this).removeClass("in");

            }

        });

Also whenever or whatever I use the .collapse method on, I get a javascript error saying that object has no method collapse.

The in class is just an indicator that a section is open. The Javascript module applies the same inline styles as .in does, so removing the class is insufficient.

You need to use the module's API to programmatically interact with the accordion, via the .collapse() method:

$('.accordion-body').each(function(){

    if ($(this).hasClass('in')) {

        $(this).collapse('toggle');

    }

});

Or, you can condense this down to:

$('.accordion-body.in').collapse('toggle');

If you want only to collapse any open sections:

$('.accordion-body').collapse('hide');

If you want only to expanded any closed sections:

$('.accordion-body').collapse('show');

Here is another solution:

/**

 * Make an accordion active

 * @param {String} id ID of the accordion

 */

var activateAccordion = function (id) {

    // Get the parents

    var parents = $('a[href="#' + id + '"]').parents('.panel-group').children('.panel');



    // Go through each of the parents

    $.each(parents, function (idx, obj) {

        // Check if the child exists

        var find = $(obj).find('a[href="#' + id + '"]'),

            children = $(obj).children('.panel-collapse');



        if (find.length > 0) {

            // Show the selected child

            children.removeClass('collapse');

            children.addClass('in');

        } else {

            // Hide the others

            children.removeClass('in');

            children.addClass('collapse');

        }

    });

};

The important part of the code is the combination, remembering the .collapse class, not just using .in:

// Show the selected child

children.removeClass('collapse');

children.addClass('in');

and

// Hide the others

children.removeClass('in');

children.addClass('collapse');

The above example has been tested in Twitter's Bootstrap v3.3.4

This works for accordions in Bootstrap 3:

var selector = $('.panel-heading a[data-toggle="collapse"]');

selector.on('click',function() {

  var self = this;

  if ($(this).hasClass('collapsed')) {

    $.each(selector, function(key, value) {

      if (!$(value).hasClass('collapsed') && value != self) {

        $(value).trigger('click');

      }

    });

  }

});

I'm simulating a click of the other accordion tabs with $(value).trigger('click');. According to the API you should just be able to use the .collapse() method i.e. $(value).collapse('hide');. But it doesn't work for some reason so trigger it is...

For this kind of problem use addClass("in"); only because of using ".collapse('toggle/Hide/Show');" will disturb the future toggle functionality.

Another related use case is when we have forms inside accordions & we want to expand accordion with validation errors. Extending the answer by Daniel Wright
https://stackoverflow.com/a/12698720/6504104, we can do something like

/**

 * Expands accordions that have fields with errors

 *

 */

var _expandAccordions = function () {

    $form           = $('.my-input-form');

    // you can adjust the following lines to match your form structure / error classes

    var $formGroups = $form.find('.form-group.has-error');  

    var $accordions = $formGroups.closest('.accordion-body');



    $accordions.each(function () {

        $(this).collapse('show');

    });

};

I did,

$('.mb-0').click(function(){

  $('.collapse').collapse('hide');

  $('.collapse.in').collapse('show');

});

and this works for me

Using Bootstrap 4 add the following buttons inside the card body

<input type="button" class="btn btn-secondary btn-block btn-sm mt-3 text-center card-proceed-next" value="Proceed" />

<input type="button" class="btn btn-secondary btn-block btn-sm mt-3 text-center card-proceed-prev" value="Previous" />

Add the following javascript (includes Azhar Khattak show panels with validation errors):

$(function () {

    $('.card-proceed-next').click(function (e) {

        e.preventDefault();

        $(e.target).closest('.collapse').collapse('hide'); // hide current accordion panel

        $(e.target).closest('.card').next('.card').find('.collapse').addClass('show'); // show next accordion panel

    });



    $('.card-proceed-prev').click(function (e) {

        e.preventDefault();

        $(e.target).closest('.collapse').collapse('hide'); // hide current accordion panel

        $(e.target).closest('.card').prev('.card').find('.collapse').addClass('show'); // show previous accordion panel

    });



    var $elErrors = $('#accordion').find('.field-validation-error'); // elements with error class

    var $accordionsWithErrors = $elErrors.closest('.collapse'); // accordions with error elements 

    if ($accordionsWithErrors.length > 0) $('.collapse').collapse(); // collapse all accordion panels due to the first accordion panel shown as default

    $accordionsWithErrors.each(function () {

        $(this).addClass('show'); // show accordion panels with error messages

    });

});