https://www.sethsgivingtree.org/wp-content/themes/smooth-blog/assets/js/navigation.js?ver=20151215

1/**
2 * File navigation.js.
3 *
4 * Handles toggling the navigation menu for small screens and enables TAB key
5 * navigation support for dropdown menus.
6 */
7( function( $ ) {
8	var container, button, menu, links, i, len;
9
10	// Add svg icon to submenu item.
11	var svg = '<svg class="icon-down" viewBox="0 0 129 129"><path d="m121.3,34.6c-1.6-1.6-4.2-1.6-5.8,0l-51,51.1-51.1-51.1c-1.6-1.6-4.2-1.6-5.8,0-1.6,1.6-1.6,4.2 0,5.8l53.9,53.9c0.8,0.8 1.8,1.2 2.9,1.2 1,0 2.1-0.4 2.9-1.2l53.9-53.9c1.7-1.6 1.7-4.2 0.1-5.8z"/></svg>';
12	var dropdownToggle = $( '<button />', { 'class': 'dropdown-toggle', 'aria-expanded': false });
13	dropdownToggle.append( svg );
14	$( '.main-navigation' ).find( '.menu-item-has-children > a, .page_item_has_children > a' ).after( dropdownToggle );
15
16
17	container = document.getElementById( 'site-navigation' );
18	if ( ! container ) {
19		return;
20	}
21
22	button = container.getElementsByTagName( 'button' )[0];
23	if ( 'undefined' === typeof button ) {
24		return;
25	}
26
27	menu = container.getElementsByTagName( 'ul' )[0];
28
29	// Hide menu toggle button if menu is empty and return early.
30	if ( 'undefined' === typeof menu ) {
31		button.style.display = 'none';
32		return;
33	}
34
35	menu.setAttribute( 'aria-expanded', 'false' );
36	if ( -1 === menu.className.indexOf( 'nav-menu' ) ) {
37		menu.className += ' nav-menu';
38	}
39
40	button.onclick = function() {
41		if ( -1 !== container.className.indexOf( 'toggled' ) ) {
42			container.className = container.className.replace( ' toggled', '' );
43			button.setAttribute( 'aria-expanded', 'false' );
44			menu.setAttribute( 'aria-expanded', 'false' );
45		} else {
46			container.className += ' toggled';
47			button.setAttribute( 'aria-expanded', 'true' );
48			menu.setAttribute( 'aria-expanded', 'true' );
49		}
50	};
51
52	// Get all the link elements within the menu.
53	links    = menu.getElementsByTagName( 'a' );
54
55	// Each time a menu link is focused or blurred, toggle focus.
56	for ( i = 0, len = links.length; i < len; i++ ) {
57		links[i].addEventListener( 'focus', toggleFocus, true );
58		links[i].addEventListener( 'blur', toggleFocus, true );
59	}
60
61	/**
62	 * Sets or removes .focus class on an element.
63	 */
64	function toggleFocus() {
65		var self = this;
66
67		// Move up through the ancestors of the current link until we hit .nav-menu.
68		while ( -1 === self.className.indexOf( 'nav-menu' ) ) {
69
70			// On li elements toggle the class .focus.
71			if ( 'li' === self.tagName.toLowerCase() ) {
72				if ( -1 !== self.className.indexOf( 'focus' ) ) {
73					self.className = self.className.replace( ' focus', '' );
74				} else {
75					self.className += ' focus';
76				}
77			}
78
79			self = self.parentElement;
80		}
81	}
82
83	/**
84	 * Toggles `focus` class to allow submenu access on tablets.
85	 */
86	( function( container ) {
87		var touchStartFn, i,
88			parentLink = container.querySelectorAll( '.menu-item-has-children > a, .page_item_has_children > a' );
89
90		if ( 'ontouchstart' in window ) {
91			touchStartFn = function( e ) {
92				var menuItem = this.parentNode, i;
93
94				if ( ! menuItem.classList.contains( 'focus' ) ) {
95					e.preventDefault();
96					for ( i = 0; i < menuItem.parentNode.children.length; ++i ) {
97						if ( menuItem === menuItem.parentNode.children[i] ) {
98							continue;
99						}
100						menuItem.parentNode.children[i].classList.remove( 'focus' );
101					}
102					menuItem.classList.add( 'focus' );
103				} else {
104					menuItem.classList.remove( 'focus' );
105				}
106			};
107
108			for ( i = 0; i < parentLink.length; ++i ) {
109				parentLink[i].addEventListener( 'touchstart', touchStartFn, false );
110			}
111		}
112	}( container ) );
113} )( jQuery );