向wp_list_table分页添加搜索值

Question

我有一个使用WordPress的自定义wp_list_table表，其中有一个搜索字段:搜索运行良好，但是当有多个页面的结果时，搜索值不会添加到分页链接中。以下是我的完整代码：

if ( ! class_exists( 'WP_List_Table' ) ) {
    require_once( ABSPATH . 'wp-admin/includes/class-wp-list-table.php' );
}

class Customers_List extends WP_List_Table {

    /** Class constructor */
    public function __construct() {

        parent::__construct( [
            'singular' => __( 'Order', 'sp' ), //singular name of the listed records
            'plural'   => __( 'Orders', 'sp' ), //plural name of the listed records
            'ajax'     => false //does this table support ajax?
        ] );

    }


    /**
     * Retrieve customers data from the database
     *
     * @param int $per_page
     * @param int $page_number
     *
     * @return mixed
     */
    public static function get_customers( $per_page = 5, $page_number = 1 ) {

        global $wpdb;

        $sql = "SELECT * FROM old_order";

        if( ! empty( $_REQUEST['s'] ) ){
                        $search = esc_sql( $_REQUEST['s'] );
            $sql .= " WHERE firstname LIKE '%{$search}%'";
            $sql .= " OR lastname LIKE '%{$search}%'";
            $sql .= " OR order_id = '{$search}'";
        }

        if ( ! empty( $_REQUEST['orderby'] ) ) {
            $sql .= ' ORDER BY ' . esc_sql( $_REQUEST['orderby'] );
            $sql .= ! empty( $_REQUEST['order'] ) ? ' ' . esc_sql( $_REQUEST['order'] ) : ' ASC';
        }

        $sql .= " LIMIT $per_page";
        $sql .= ' OFFSET ' . ( $page_number - 1 ) * $per_page;

        // echo $sql;

        $result = $wpdb->get_results( $sql, 'ARRAY_A' );

        return $result;
    }


    /**
     * Delete a customer record.
     *
     * @param int $id customer ID
     */
    public static function delete_customer( $id ) {
        global $wpdb;

        $wpdb->delete(
            "old_order",
            [ 'ID' => $id ],
            [ '%d' ]
        );
    }


    /**
     * Returns the count of records in the database.
     *
     * @return null|string
     */
    public static function record_count() {
        global $wpdb;

        $sql = "SELECT COUNT(*) FROM old_order";

        if( ! empty( $_REQUEST['s'] ) ){
            $search = esc_sql( $_REQUEST['s'] );
            $sql .= " WHERE firstname LIKE '%{$search}%'";
            $sql .= " OR lastname LIKE '%{$search}%'";
            $sql .= " OR order_id LIKE '%{$search}%'";
        }

        return $wpdb->get_var( $sql );
    }


    /** Text displayed when no customer data is available */
    public function no_items() {
        _e( 'No orders available..', 'sp' );
    }


    /**
     * Render a column when no column specific method exist.
     *
     * @param array $item
     * @param string $column_name
     *
     * @return mixed
     */
    public function column_default( $item, $column_name ) {
        switch ( $column_name ) {
            case 'order_id':
                return $item[ $column_name ];
            case 'firstname':
                return $item[ $column_name ];
            case 'lastname':
                return $item[ $column_name ];
            case 'total':
                return "$" . number_format( $item[ $column_name ] );
            case 'date_added':
                return date('m/d/Y g:i:s A', strtotime( $item[ $column_name ] ) );
            default:
                return print_r( $item, true ); //Show the whole array for troubleshooting purposes
        }
    }

    /**
     * Render the bulk edit checkbox
     *
     * @param array $item
     *
     * @return string
     */
    function column_cb( $item ) {
        return sprintf(
            '', $item['ID']
        );
    }


    /**
     * Method for name column
     *
     * @param array $item an array of DB data
     *
     * @return string
     */
    function column_name( $item ) {

        $delete_nonce = wp_create_nonce( 'sp_delete_customer' );

        $title = '' . $item['name'] . '';

        $actions = [
            'delete' => sprintf( 'Delete', esc_attr( $_REQUEST['page'] ), 'delete', absint( $item['ID'] ), $delete_nonce )
        ];

        return $title . $this->row_actions( $actions );
    }


    /**
     *  Associative array of columns
     *
     * @return array
     */
    function get_columns() {
        $columns = [
            'cb'      => '',
            'order_id'    => __( 'Order ID', 'sp' ),
            'firstname' => __( 'First Name', 'sp' ),
            'lastname'    => __( 'Last Name', 'sp' ),
            'total'    => __( 'Total', 'sp' ),
            'date_added'    => __( 'Date Added', 'sp' )
        ];

        return $columns;
    }


    /**
     * Columns to make sortable.
     *
     * @return array
     */
    public function get_sortable_columns() {
        $sortable_columns = array(
            'order_id' => array( 'order_id', true ),
            'firstname' => array( 'firstname', true ),
            'lastname' => array( 'lastname', true )
        );

        return $sortable_columns;
    }

    /**
     * Returns an associative array containing the bulk action
     *
     * @return array
     */
    public function get_bulk_actions() {
        $actions = [
            'bulk-delete' => 'Delete'
        ];

        return $actions;
    }


    /**
     * Handles data query and filter, sorting, and pagination.
     */
    public function prepare_items( ) {

        $this->_column_headers = $this->get_column_info();

        /** Process bulk action */
        $this->process_bulk_action();

        $per_page     = $this->get_items_per_page( 'customers_per_page', 20 );
        $current_page = $this->get_pagenum();
        $total_items  = self::record_count();

        $this->set_pagination_args( [
            'total_items' => $total_items, //WE have to calculate the total number of items
            'per_page'    => $per_page //WE have to determine how many items to show on a page
        ] );

        $this->items = self::get_customers( $per_page, $current_page );
    }

    public function process_bulk_action() {

        //Detect when a bulk action is being triggered...
        if ( 'delete' === $this->current_action() ) {

            // In our file that handles the request, verify the nonce.
            $nonce = esc_attr( $_REQUEST['_wpnonce'] );

            if ( ! wp_verify_nonce( $nonce, 'sp_delete_customer' ) ) {
                die( 'Go get a life script kiddies' );
            }
            else {
                self::delete_customer( absint( $_GET['customer'] ) );

                        // esc_url_raw() is used to prevent converting ampersand in url to "#038;"
                        // add_query_arg() return the current url
                        wp_redirect( esc_url_raw(add_query_arg()) );
                exit;
            }

        }

        // If the delete bulk action is triggered
        if ( ( isset( $_POST['action'] ) && $_POST['action'] == 'bulk-delete' )
             || ( isset( $_POST['action2'] ) && $_POST['action2'] == 'bulk-delete' )
        ) {

            $delete_ids = esc_sql( $_POST['bulk-delete'] );

            // loop over the array of record IDs and delete them
            foreach ( $delete_ids as $id ) {
                self::delete_customer( $id );

            }

            // esc_url_raw() is used to prevent converting ampersand in url to "#038;"
                // add_query_arg() return the current url
                wp_redirect( esc_url_raw(add_query_arg()) );
            exit;
        }
    }

}


class SP_Plugin {

    // class instance
    static $instance;

    // customer WP_List_Table object
    public $customers_obj;

    // class constructor
    public function __construct() {
        add_filter( 'set-screen-option', [ __CLASS__, 'set_screen' ], 10, 3 );
        add_action( 'admin_menu', [ $this, 'plugin_menu' ] );
    }


    public static function set_screen( $status, $option, $value ) {
        return $value;
    }

    public function plugin_menu() {

        $hook = add_menu_page(
            'Order Lookup',
            'Order Lookup',
            'manage_options',
            'wp_list_table_class',
            [ $this, 'plugin_settings_page' ]
        );

        add_action( "load-$hook", [ $this, 'screen_option' ] );

    }


    /**
     * Plugin settings page
     */
    public function plugin_settings_page() {
        ?>
        
            Previous Order System Lookup

            
                
                    
                        
                            
                                customers_obj->prepare_items();
                                $this->customers_obj->search_box('Search', 'search');
                                $this->customers_obj->display(); ?>
                            
                        
                    
                
                

            
        
     'Customers',
            'default' => 20,
            'option'  => 'customers_per_page'
        ];

        add_screen_option( $option, $args );

        $this->customers_obj = new Customers_List();
    }


    /** Singleton instance */
    public static function get_instance() {
        if ( ! isset( self::$instance ) ) {
            self::$instance = new self();
        }

        return self::$instance;
    }

}


add_action( 'plugins_loaded', function () {
    SP_Plugin::get_instance();
} );

除了在有多个页面时将搜索值添加到分页链接之外，所有内容都按预期的方式工作。因此，当您单击“next”时，它移除搜索值并返回所有结果(在下一页上)。我使用这个Gist作为参考：https://gist.github.com/paulund/7659452

Answer 1

通过将页面变量作为隐藏字段传递，解决了我的问题：

    customers_obj->prepare_items();
    $this->customers_obj->search_box('Search', 'search');
    $this->customers_obj->display(); ?>

Answer 2

我通过克隆WP列表表的分页功能并在url中添加搜索变量来实现这一点。下面是相同的代码。

受保护的函数分页( $which ){如果(空($this->_$which_args)){返回；}

    $total_items     = $this->_pagination_args['total_items'];
    $total_pages     = $this->_pagination_args['total_pages'];
    $infinite_scroll = false;

    if ( isset( $this->_pagination_args['infinite_scroll'] ) ) {
        $infinite_scroll = $this->_pagination_args['infinite_scroll'];
    }

    if ( 'top' === $which && $total_pages > 1 ) {
        $this->screen->render_screen_reader_content( 'heading_pagination' );
    }

    $output = '' . sprintf( _n( '%s item', '%s items', $total_items ), number_format_i18n( $total_items ) ) . '';

    $current              = $this->get_pagenum();
    $removable_query_args = wp_removable_query_args();

    $current_url = set_url_scheme( 'http://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] );

    $current_url = remove_query_arg( $removable_query_args, $current_url );

    if( isset($_REQUEST['s'] ) ){
        $current_url = add_query_arg( 's', $_REQUEST['s'], $current_url );
    }

    $page_links = array();

    $total_pages_before = '';
    $total_pages_after  = '';

    $disable_first = $disable_last = $disable_prev = $disable_next = false;

    if ( $current == 1 ) {
        $disable_first = true;
        $disable_prev  = true;
    }
    if ( $current == 2 ) {
        $disable_first = true;
    }
    if ( $current == $total_pages ) {
        $disable_last = true;
        $disable_next = true;
    }
    if ( $current == $total_pages - 1 ) {
        $disable_last = true;
    }

    if ( $disable_first ) {
        $page_links[] = '«';
    } else {
        $page_links[] = sprintf(
            "%s%s",
            esc_url( remove_query_arg( 'paged', $current_url ) ),
            __( 'First page' ),
            '«'
        );
    }

    if ( $disable_prev ) {
        $page_links[] = '‹';
    } else {
        $page_links[] = sprintf(
            "%s%s",
            esc_url( add_query_arg( 'paged', max( 1, $current - 1 ), $current_url ) ),
            __( 'Previous page' ),
            '‹'
        );
    }

    if ( 'bottom' === $which ) {
        $html_current_page  = $current;
        $total_pages_before = '' . __( 'Current Page' ) . '';
    } else {
        $html_current_page = sprintf(
            "%s",
            '' . __( 'Current Page' ) . '',
            $current,
            strlen( $total_pages )
        );
    }
    $html_total_pages = sprintf( "%s", number_format_i18n( $total_pages ) );
    $page_links[]     = $total_pages_before . sprintf( _x( '%1$s of %2$s', 'paging' ), $html_current_page, $html_total_pages ) . $total_pages_after;

    if ( $disable_next ) {
        $page_links[] = '›';
    } else {
        $page_links[] = sprintf(
            "%s%s",
            esc_url( add_query_arg( 'paged', min( $total_pages, $current + 1 ), $current_url ) ),
            __( 'Next page' ),
            '›'
        );
    }

    if ( $disable_last ) {
        $page_links[] = '»';
    } else {
        $page_links[] = sprintf(
            "%s%s",
            esc_url( add_query_arg( 'paged', $total_pages, $current_url ) ),
            __( 'Last page' ),
            '»'
        );
    }

    $pagination_links_class = 'pagination-links';
    if ( ! empty( $infinite_scroll ) ) {
        $pagination_links_class .= ' hide-if-js';
    }
    $output .= "\n" . join( "\n", $page_links ) . '';

    if ( $total_pages ) {
        $page_class = $total_pages < 2 ? ' one-page' : '';
    } else {
        $page_class = ' no-pages';
    }

    $this->_pagination = "$output";
    echo $this->_pagination;
}