[SonataAdmin] Show the save button on scroll down

sonata_edit.js

$(document).ready(function() {

    /** Update button **/
    if (null !== location.pathname.match(/\/edit/)) {
        $(window).scroll(function() {
            if ($(window).height() + $(window).scrollTop() > $(document).height() - 10 || $(this).scrollTop() < 100) {
                $('#save-button').fadeOut();
            }
            else {
                $('#save-button').fadeIn();
            }
        });
        
        $('#save-button').bind('click', function() {
            $('form').submit();
        });
    }

});

sonata_layout.twig

{% extends 'SonataAdminBundle::standard_layout.html.twig' %}

{% block javascripts %}
    {{ parent() }}
    <script src="{{ asset('bundles/mybundle/js/sonata_edit.js') }}" type="text/javascript"></script>
{% endblock %}

{% block sonata_top_nav_menu %}
    <div class="navbar-custom-menu">
        <ul class="nav navbar-nav">
            <li class="dropdown">
                <div id="save-button">
                    <button type="submit" class="btn btn-success" name="btn_update_and_edit">
                        <i class="fa fa-save"></i>
                    </button>
                </div>
            </li>
            <li class="dropdown">
                <a class="dropdown-toggle" data-toggle="dropdown" href="#">
                    <i class="fa fa-plus-square fa-fw"></i> <i class="fa fa-caret-down"></i>
                </a>
                {% include admin_pool.getTemplate('add_block') %}
            </li>
            <li class="dropdown user-menu">
                <a class="dropdown-toggle" data-toggle="dropdown" href="#">
                    <i class="fa fa-user fa-fw"></i> <i class="fa fa-caret-down"></i>
                </a>
                <ul class="dropdown-menu dropdown-user">
                    {% include admin_pool.getTemplate('user_block') %}
                </ul>
            </li>
        </ul>
    </div>
{% endblock %}