控制器编码器中的功能视图

我正在制作新闻部分的示例，如下面的链接所示:http://www.codeigniter.com/userguide2/tutorial/news_section.html

包含控制器索引和视图两个函数。当我从控制器中删除视图函数时，我得到了相同的输出。有人能帮我理解控制器中功能视图的需求吗?

<?php
class News extends CI_Controller {
    public function __construct()
    {
        parent::__construct();
        $this->load->model('news_model');
    }
   public function index()
   {
        $data['news'] = $this->news_model->get_news();
        $data['title'] = 'News archive';
        $this->load->view('templates/header', $data);
        $this->load->view('news/index', $data);
        $this->load->view('templates/footer');
    }
    public function view($slug)
    {
        $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('templates/header', $data);
        $this->load->view('news/view', $data);
        $this->load->view('templates/footer');
    }

}