我想显示从两个表生成的列表。我有一个带有快捷码的页面，可以按照我的要求加载信息。短代码运行一个名为member_list. 在这个函数中，我有一个表单，其中有一篇帖子，在提交表单时运行相同的函数。我检查哪个操作正在调用函数并添加<?php get_header(); ?> 和<?php get_footer(); 当从岗位上跑开时。我的问题是，这篇文章的结果页面失去了格式，并抛出了其中四条消息

Notice: Trying to get property of non-object in D:\\www.foo.com\\wp-includes\\admin-bar.php on line 6. 

function member_directory($sort_order, $first_time) {
    global $wpdb;
    if (!$first_time){
        get_header();
    }

    if ($sort_order == 1) {
        $where_clause = "LotNoSorting";
    } elseif ($sort_order == 2) {
        $where_clause = "last_name, first_name";
    } elseif ($sort_order == 3) {
        $where_clause = "recordedsubdivision, block, lotnum";
    } elseif($sort_order == 4){
        $where_clause = "street, housenum";
    } else {
        die ("Internal Error 1");
    }
    $sql =  "SELECT subscr_id, first_name, last_name, block, housenum, lotnum, lotno, lotnosorting, recordedsubdivision, street FROM wp_swpm_members_tbl LEFT OUTER JOIN plcoa_lots ON wp_swpm_members_tbl.subscr_id = plcoa_lots.lotno WHERE block <> \'\' ORDER BY " . $where_clause ;
    $query = $wpdb->get_results($sql);
    if (!empty ($query) ) {
    ?>
    <table>
        <form method="post" action="http://priestlakecoa.org/wp-admin/admin-post.php">
            <td > 
                <input type="submit"  value="Lot #" name="lot">
                <input type="hidden" name="action" value="member_directory">
            </td>
            <td >           
                <input type="submit" value="Name" name="name">
                <input type="hidden" name="action" value="member_directory">
            </td>       
            <td >
                <input type="submit"  value="Subdivision - Blk / Lot" name="subdivision">
                <input type="hidden" name="action" value="member_directory">
            </td>        
            <td >
            <input type="submit" value="Address" name="address">
                <input type="hidden" name="action" value="member_directory">
            </td>       
        </form>

        <?php
            foreach ($query as $row) {
        ?>
        <tr>
            <td><?php echo $row->subscr_id; ?></td>
            <td><?php echo $row->first_name . " " . $row->last_name; ?></td>
            <td><?php echo $row->recordedsubdivision . " " . $row->block . "/" .$row->lotnum; ?></td>
            <td><?php echo $row->housenum . " " . $row->street ; ?></td>
        </tr> 
        <?php
            }
            if (!$first_time){
                get_footer();
            }
        ?>
    </table>
        <?php

        } else {

            echo "Nothing found";
        }
}