我的资源文件夹的文件夹结构如下所示
project_root_folder - ＆gt;资产 - ＆gt; css - ＆gt; {stylesheet.css，sample.css，something.css}
project_root_folder - ＆gt;资产 - ＆gt; js - ＆gt; {jquery.min.js，sample.js，something.js}
project_root_folder - ＆gt;资产 - ＆gt;高速缓存
project_root_folder - ＆gt; system - ＆gt;插件 - ＆gt; csstidy
project_root_folder - ＆gt; system - ＆gt;插件 - ＆gt; jsmin.php
application/config/assetlibpro.php
$config['alp_csstidy_basepath'] = "/system/plugins/csstidy";
$config['alp_jsmin'] = "/system/plugins/jsmin.php";
$config['alp_asset_dir'] = 'assets/';//TRAILING SLASH!
$config['alp_cache_dir_css'] = 'assets/cache/';//TRAILING SLASH!
$config['alp_cache_dir_js'] = 'assets/cache/';//TRAILING SLASH!
在我的config/autoload.php
$autoload['libraries'] = array('assetlibpro');
在我的控制器中，
$this->assetlibpro->add_css('stylesheet.css'); // Stylesheet file
$this->assetlibpro->add_js('jquery-2.1.0.min.js'); // JavaScript file
$data['common_css']=$this->assetlibpro->output('css'); // Store the CSS in the variable
$data['homepage_js']=$this->assetlibpro->output('js'); // Store the JS in the variable
$this->load->view('main-homepage', $data); // Load homepage view
在main-homepage.php中，
echo $common_css;
echo $homepage_js;
但页面不会抛出任何错误或输出CSS和JS。我做错了什么？