Update: 22.01.2019, 13.41 I optimized the solution by jhay, which also supports closing and opening same or different dialogs when for example stepping from one detail data to another forwards or backwards.
(function ($, window) {
'use strict';
var MultiModal = function (element) {
this.$element = $(element);
this.modalIndex = 0;
};
MultiModal.BASE_ZINDEX = 1040;
/* Max index number. When reached just collate the zIndexes */
MultiModal.MAX_INDEX = 5;
MultiModal.prototype.show = function (target) {
var that = this;
var $target = $(target);
// Bootstrap triggers the show event at the beginning of the show function and before
// the modal backdrop element has been created. The timeout here allows the modal
// show function to complete, after which the modal backdrop will have been created
// and appended to the DOM.
// we only want one backdrop; hide any extras
setTimeout(function () {
/* Count the number of triggered modal dialogs */
that.modalIndex++;
if (that.modalIndex >= MultiModal.MAX_INDEX) {
/* Collate the zIndexes of every open modal dialog according to its order */
that.collateZIndex();
}
/* Modify the zIndex */
$target.css('z-index', MultiModal.BASE_ZINDEX + (that.modalIndex * 20) + 10);
/* we only want one backdrop; hide any extras */
if (that.modalIndex > 1)
$('.modal-backdrop').not(':first').addClass('hidden');
that.adjustBackdrop();
});
};
MultiModal.prototype.hidden = function (target) {
this.modalIndex--;
this.adjustBackdrop();
if ($('.modal.in').length === 1) {
/* Reset the index to 1 when only one modal dialog is open */
this.modalIndex = 1;
$('.modal.in').css('z-index', MultiModal.BASE_ZINDEX + 10);
var $modalBackdrop = $('.modal-backdrop:first');
$modalBackdrop.removeClass('hidden');
$modalBackdrop.css('z-index', MultiModal.BASE_ZINDEX);
}
};
MultiModal.prototype.adjustBackdrop = function () {
$('.modal-backdrop:first').css('z-index', MultiModal.BASE_ZINDEX + (this.modalIndex * 20));
};
MultiModal.prototype.collateZIndex = function () {
var index = 1;
var $modals = $('.modal.in').toArray();
$modals.sort(function(x, y)
{
return (Number(x.style.zIndex) - Number(y.style.zIndex));
});
for (i = 0; i < $modals.length; i++)
{
$($modals[i]).css('z-index', MultiModal.BASE_ZINDEX + (index * 20) + 10);
index++;
};
this.modalIndex = index;
this.adjustBackdrop();
};
function Plugin(method, target) {
return this.each(function () {
var $this = $(this);
var data = $this.data('multi-modal-plugin');
if (!data)
$this.data('multi-modal-plugin', (data = new MultiModal(this)));
if (method)
data[method](target);
});
}
$.fn.multiModal = Plugin;
$.fn.multiModal.Constructor = MultiModal;
$(document).on('show.bs.modal', function (e) {
$(document).multiModal('show', e.target);
});
$(document).on('hidden.bs.modal', function (e) {
$(document).multiModal('hidden', e.target);
});}(jQuery, window));