codeigniter视图显示问题

Question

我创建了CRUD操作，我的视图功能没有显示显示404错误页面的视图页面。

我的代码如下

Controller

public function view($slug = NULL)
    {
        $data['news_item'] = $this->news_model->get_news($slug);

        if (empty($data['news_item'])) {
            show_404();
        }

        $data['title'] = $data['news_item']['title'];

        $this->load->view('user/header', $data);
        $this->load->view('news/view', $data);
        $this->load->view('user/footer');
    }

Model

public function get_news($slug = FALSE)
    {
        if ($slug === FALSE)
        {
            $query = $this->db->get_where('news', array('user_id' => $this->session->userdata('user_id')));
            return $query->result_array(); // $query->result(); // returns object
        }

        $query = $this->db->get_where('news', array('slug' => $slug, 'user_id' => $this->session->userdata('user_id')));
        return $query->row_array(); // $query->row(); // returns object


    }

View

<?php
echo '<h2>'.$news_item['title'].'</h2>';
echo $news_item['text'];