/* --------------------------------------------------------------
datatable_fixed_header.js 2016-07-13
Gambio GmbH
http://www.gambio.de
Copyright (c) 2016 Gambio GmbH
Released under the GNU General Public License (Version 2)
[http://www.gnu.org/licenses/gpl-2.0.html]
--------------------------------------------------------------
*/
/**
* ## Enable Fixed DataTable Header
*
* The table header will remain in the viewport as the user scrolls down the page. The style change of this
* module is a bit tricky because we need to remove the thead from the normal flow, something that breaks the
* display of the table. Therefore a helper clone of the thead is used to maintain the table formatting.
*
* **Notice #1**: The .table-fixed-header class is styled by the _tables.scss and is part of this solution.
*
* **Notice #2**: This method will take into concern the .content-header element which shouldn't overlap the
* table header.
*
* @module Admin/Extensions/datatable_fixed_header
*/
gx.extensions.module('datatable_fixed_header', [], function (data) {
'use strict';
// ------------------------------------------------------------------------
// VARIABLES
// ------------------------------------------------------------------------
/**
* Module Selector
*
* @type {jQuery}
*/
const $this = $(this);
/**
* Table Header Selector
*
* @type {jQuery}
*/
const $thead = $this.children('thead');
/**
* Module Instance
*
* @type {Object}
*/
const module = {};
/**
* Marks the end of the table.
*
* This value is used to stop the fixed header when the user reaches the end of the table.
*
* @type {Number}
*/
let tableOffsetBottom;
// ------------------------------------------------------------------------
// FUNCTIONS
// ------------------------------------------------------------------------
/**
* On DataTable Draw Event
*
* Re-calculate the table bottom offset value.
*/
function _onDataTableDraw() {
tableOffsetBottom = $this.offset().top + $this.height() - $thead.height();
}
/**
* On DataTable Initialization
*
* Modify the table HTML and set the required event handling for the fixed header functionality.
*/
function _onDataTableInit() {
const $mainHeader = $('#main-header');
const $contentHeader = $('.content-header');
const $clone = $thead.clone();
const originalTop = $thead.offset().top;
let isFixed = false;
let rollingAnimationInterval = null;
$clone
.hide()
.addClass('table-fixed-header-helper')
.prependTo($this);
$(window)
.on('scroll', function () {
const scrollTop = $(window).scrollTop();
if (!isFixed && scrollTop + $mainHeader.outerHeight() > originalTop) {
$this.addClass('table-fixed-header');
$thead
.outerWidth($this.outerWidth())
.addClass('fixed');
$clone.show();
isFixed = true;
} else if (isFixed && scrollTop + $mainHeader.outerHeight() < originalTop) {
$this.removeClass('table-fixed-header');
$thead
.outerWidth('')
.removeClass('fixed');
$clone.hide();
isFixed = false;
}
if (scrollTop >= tableOffsetBottom) {
$thead.removeClass('fixed');
} else if ($(window).scrollTop() < tableOffsetBottom && !$thead.hasClass('fixed')) {
$thead.addClass('fixed');
}
})
.on('content_header:roll_in', function () {
rollingAnimationInterval = setInterval(() => {
$thead.css('top', $contentHeader.position().top + $contentHeader.outerHeight());
if ($contentHeader.hasClass('fixed')) {
clearInterval(rollingAnimationInterval);
}
}, 1);
})
.on('content_header:roll_out', function () {
clearInterval(rollingAnimationInterval);
$thead.css('top', $mainHeader.outerHeight());
});
}
// ------------------------------------------------------------------------
// INITIALIZATION
// ------------------------------------------------------------------------
module.init = function (done) {
$(window).on('JSENGINE_INIT_FINISHED', () => {
$this
.on('draw.dt', _onDataTableDraw)
.on('init.dt', _onDataTableInit);
// Setup fixed header functionality if the table is already initialized.
if ($this.DataTable().ajax.json() !== undefined) {
_onDataTableInit();
}
});
done();
};
return module;
});
