themes-wordpress/seedlet/assets/js/primary-navigation.js

/**
 * File primary-navigation.js.
 *
 * Required to open and close the mobile navigation.
 */
( function () {
	/**
	 * Menu Toggle Behaviors
	 *
	 * @param {Element} element
	 */
	var navMenu = function ( id ) {
		var wrapper = document.body; // this is the element to which a CSS class is added when a mobile nav menu is open
		var openButton = document.getElementById( id + '-open-menu' );
		var closeButton = document.getElementById( id + '-close-menu' );

		if ( openButton && closeButton ) {
			openButton.onclick = function () {
				wrapper.classList.add( id + '-navigation-open' );
				wrapper.classList.add( 'lock-scrolling' );
				closeButton.focus();
			};

			closeButton.onclick = function () {
				wrapper.classList.remove( id + '-navigation-open' );
				wrapper.classList.remove( 'lock-scrolling' );
				openButton.focus();
			};
		}

		/**
		 * Trap keyboard navigation in the menu modal.
		 * Adapted from TwentyTwenty
		 */
		document.addEventListener( 'keydown', function ( event ) {
			if ( ! wrapper.classList.contains( id + '-navigation-open' ) ) {
				return;
			}
			var modal,
				elements,
				selectors,
				lastEl,
				firstEl,
				activeEl,
				tabKey,
				shiftKey,
				escKey;

			modal = document.querySelector( '.' + id + '-navigation' );
			selectors = 'input, a, button';
			elements = modal.querySelectorAll( selectors );
			elements = Array.prototype.slice.call( elements );
			elements = elements.filter( function ( el ) {
				return ! el.classList.contains( 'woocommerce-cart-link' ); // ignore this element because it's hidden on mobile
			} );
			tabKey = event.keyCode === 9;
			shiftKey = event.shiftKey;
			escKey = event.keyCode === 27;
			activeEl = document.activeElement;
			lastEl = elements[ elements.length - 1 ];
			firstEl = elements[ 0 ];

			if ( escKey ) {
				event.preventDefault();
				wrapper.classList.remove(
					id + '-navigation-open',
					'lock-scrolling'
				);
				openButton.focus();
			}

			if ( ! shiftKey && tabKey && lastEl === activeEl ) {
				event.preventDefault();
				firstEl.focus();
			}

			if ( shiftKey && tabKey && firstEl === activeEl ) {
				event.preventDefault();
				lastEl.focus();
			}

			// If there are no elements in the menu, don't move the focus
			if ( tabKey && firstEl === lastEl ) {
				event.preventDefault();
			}
		} );
	};

	window.addEventListener( 'load', function () {
		new navMenu( 'primary' );
		new navMenu( 'woo' );
	} );
} )();