rilwis/meta-box

<?php
defined( 'ABSPATH' ) || die;

/**
 * The select tree field.
 */
class RWMB_Select_Tree_Field extends RWMB_Select_Advanced_Field {
    /**
     * Get field HTML.
     *
     * @param mixed $meta  Meta value.
     * @param array $field Field parameters.
     * @return string
     */
    public static function html( $meta, $field ) {
        $options = self::transform_options( $field['options'] );
        $walker  = new RWMB_Walker_Select_Tree( $field, $meta );
        return $options ? $walker->walk( $options ) : '';
    }

    public static function admin_enqueue_scripts() {
        parent::admin_enqueue_scripts();
        wp_enqueue_style( 'rwmb-select-tree', RWMB_CSS_URL . 'select-tree.css', [ 'rwmb-select' ], RWMB_VER );
        wp_style_add_data( 'rwmb-select-tree', 'path', RWMB_CSS_DIR . 'select-tree.css' );
        wp_enqueue_script( 'rwmb-select-tree', RWMB_JS_URL . 'select-tree.js', [ 'rwmb-select' ], RWMB_VER, true );
    }

    /**
     * Normalize parameters for field.
     *
     * @param array $field Field parameters.
     * @return array
     */
    public static function normalize( $field ) {
        $field['multiple'] = true;
        $field['size']     = 0;
        $field             = parent::normalize( $field );

        return $field;
    }

    /**
     * Get the attributes for a field.
     *
     * @param array $field Field parameters.
     * @param mixed $value Meta value.
     *
     * @return array
     */
    public static function get_attributes( $field, $value = null ) {
        $attributes             = parent::get_attributes( $field, $value );
        $attributes['multiple'] = false;
        $attributes['id']       = false;

        return $attributes;
    }
}