注意：未定义的变量：第21行的/Applications/XAMPP/xamppfiles/htdocs/fu.../functions.php中的帖子

Question

您好我正在尝试使用此功能从数据库中获取用户帖子作为数组，但我收到此错误，$ posts变量未定义请帮助 注意：未定义的变量：第21行的/Applications/XAMPP/xamppfiles/htdocs/fu.../functions.php中的帖子

    //the function
    function show_posts($user_id){
    global $conn,$user_id;
    $sql="SELECT post_body,post_date FROM users_posts WHERE      user_id=$user_id ORDER BY post_date DESC";
    $result=mysqli_query($conn,$sql);
    while($data=mysqli_fetch_object($result)){
        $posts[] = array(
            'post_date' => $data->post_date,
            'user_id' => $user_id,
            'post_body' => $data->post_body
        );
    }
     return $posts ;
}

    //the home page
    <h4>RECENT ACTIVITY</h4>
               <div class="panel panel-default">
                   <div class="panel-body">
                       <?php


                       $posts = show_posts($_SESSION['login']);
                       if(count($posts)){
                           foreach($posts as $key => $list){
                               echo $list['post_date'],"<br>";
                               echo $list['post_body'];
                           }


                       }

                       ?>



                   </div>
                </div>