WP Job Manager | Add custom dropdown field to admin, frontend listing, list of jobs, and search

wp-job-manager-custom-dropdown-field.php

<?php
add_filter( 'job_manager_job_listing_data_fields', 'admin_add_hours_field' );
function admin_add_hours_field( $fields ) {
	$fields['_job_hours'] = array(
		'label'			=> __( 'Job Hours', 'job_manager' ),
		'type'			=> 'select',
		'options'		=> array('Select hours', '0 - 5' => '0 - 5', '5 - 10' => '5 - 10', '10 - 15' => '10 - 15', '20 +' => '20 +', 'flexible hours' => 'flexible hours'),
		'placeholder'	=> '',
		'description'	=> ''
	);
	return $fields;
}

/* Output the Hours value on the frontend of the actual Job Listing post */
add_action( 'single_job_listing_meta_end', 'display_job_hours_data' );
function display_job_hours_data() {
	global $post;
	$hours = get_post_meta( $post->ID, '_job_hours', true );
	if ( $hours ) {
		echo '<li class="fs-job-hours">' . __( 'Hours:' ) . ' <span>' . esc_html( $hours ) . '</span></li>';
	}
}

/* Output the Hours value in the list of Jobs */
add_action( 'job_listing_meta_end', 'display_job_hours_in_list' );
function display_job_hours_in_list() {
	global $post;
	$hours = get_post_meta( $post->ID, '_job_hours', true );
	if ( $hours ) {
		echo '<li class="fs-job-hours-list">' . __( 'Hours:' ) . ' <span>' . esc_html( $hours ) . '</span></li>';
	}
}

/**
 * Add new option to the Search form 
 *
 * This can either be done with a filter (below) or the field can be added directly to the job-filters.php template file!
 *
 * job-manager-filter class handling was added in v1.23.6
 */
add_action( 'job_manager_job_filters_search_jobs_end', 'filter_by_hours_field' );
function filter_by_hours_field() {
	?>
	<div class="search_categories">
		<label for="search_categories"><?php _e( 'Hours', 'wp-job-manager' ); ?></label>
		<select name="filter_by_hours" class="job-manager-filter">
			<option value=""><?php _e( 'How many hours per week do you want to work?', 'wp-job-manager' ); ?></option>
			<option value="0-5"><?php _e( '0 - 5', 'wp-job-manager' ); ?></option>
			<option value="5-10"><?php _e( '5 - 10', 'wp-job-manager' ); ?></option>
			<option value="10-15"><?php _e( '10 - 15', 'wp-job-manager' ); ?></option>
			<option value="15-20"><?php _e( '15 - 20', 'wp-job-manager' ); ?></option>
			<option value="20+"><?php _e( '20 +', 'wp-job-manager' ); ?></option>
			<option value="flexible-hours"><?php _e( 'flexible hours', 'wp-job-manager' ); ?></option>
		</select>
	</div>
	<?php
}

/**
 * This code gets your posted field and modifies the actual job search query based on the field added via the above function
 */
add_filter( 'job_manager_get_listings', 'filter_by_hours_field_query_args', 10, 2 );
function filter_by_hours_field_query_args( $query_args, $args ) {
	if ( isset( $_POST['form_data'] ) ) {
		parse_str( $_POST['form_data'], $form_data );

		// If this is set, we are filtering by hours
		if ( ! empty( $form_data['filter_by_hours'] ) ) {
			$selected_range = sanitize_text_field( $form_data['filter_by_hours'] );
			switch ( $selected_range ) {
				case '0-5' :
					$query_args['meta_query'][] = array(
						'key'     => '_job_hours',
						'value'   => '0 - 5',
						'compare' => '=',
						'type'    => 'CHAR'
					);
				break;
				case '5-10' :
					$query_args['meta_query'][] = array(
						'key'     => '_job_hours',
						'value'   => '5 - 10',
						'compare' => '=',
						'type'    => 'CHAR'
					);
				break;
				case '10-15' :
					$query_args['meta_query'][] = array(
						'key'     => '_job_hours',
						'value'   => '10 - 15',
						'compare' => '=',
						'type'    => 'CHAR'
					);
				break;
				case '15-20' :
					$query_args['meta_query'][] = array(
						'key'     => '_job_hours',
						'value'   => '15 - 20',
						'compare' => '=',
						'type'    => 'CHAR'
					);
				break;
				case '20+' :
					$query_args['meta_query'][] = array(
						'key'     => '_job_hours',
						'value'   => '20 +',
						'compare' => '=',
						'type'    => 'CHAR'
					);
				break;
				case 'flexible-hours' :
					$query_args['meta_query'][] = array(
						'key'     => '_job_hours',
						'value'   => 'flexible hours',
						'compare' => '=',
						'type'    => 'CHAR'
					);
				break;
				default :
					$query_args['meta_query'][] = array(
					);
				break;
			}

			// This will show the 'reset' link
			add_filter( 'job_manager_get_listings_custom_filter', '__return_true' );
		}
	}
	return $query_args;
}

Excellent, though it does not add the field to the front facing post a job form.