Reply To: Add Sort by that filter by date newest or oldest

Hi,

While currently there is no out of the box filter for that, it is still possible to achieve it via a custom field filter + a bit of a custom code.

Follow the steps below:

1. Create a drop-down custom field filter for a non-existint field custom_order with these values (see this screenshot):

date||Date ASC
date_reverse||Date DESC

2. Add this code via the Code Snippets plugin or to the functions.php file in your theme/child theme directory – make sure to have a full server back-up first for safety. For more details you can check the safe coding guidelines:

add_filter(
	'asp_query_args',
	function ( $args ) {
		// The values allowed in the the_ordering variable
		$allowed_orderings = array(
			'relevance',
			'id',
			'id_reverse',
			'date',
			'date_reverse',
			'alpha',
			'alpha_reverse',
			'price',
			'price_reverse',
		);

		$ordering = '';

		foreach ( $args['post_meta_filter'] as $k => $filter ) {
			if ( $filter['key'] === 'custom_order' ) {
				$ordering = $filter['value'];
				unset( $args['post_meta_filter'][$k] );
			}
		}

		if ( $ordering === '' || !in_array($ordering, $allowed_orderings, true) ) {
			return $args;
		}

		switch ( $ordering ) {
			case 'id':
				$args['post_primary_order'] = 'id DESC';
				break;
			case 'id_reverse':
				$args['post_primary_order'] = 'id ASC';
				break;
			case 'date':
				$args['post_primary_order'] = 'post_date DESC';
				break;
			case 'date_reverse':
				$args['post_primary_order'] = 'post_date ASC';
				break;
			case 'alpha':
				$args['post_primary_order'] = 'post_title ASC';
				break;
			case 'alpha_reverse':
				$args['post_primary_order'] = 'post_title DESC';
				break;
			case 'price':
				$args['post_primary_order']          = 'customfp ASC';
				$args['post_primary_order_metatype'] = 'numeric';
				$args['_post_primary_order_metakey'] = '_price';
				break;
			case 'price_reverse':
				$args['post_primary_order']          = 'customfp DESC';
				$args['post_primary_order_metatype'] = 'numeric';
				$args['_post_primary_order_metakey'] = '_price';
				break;
			case 'relevance':
			default:
				$args['post_primary_order'] = 'relevance DESC';
				break;
		}

		return $args;
	}
);

This will convert the custom field filter into a sorting filter. In case you need help with it, let me know 🙂