最近想开发一个新的插件用来监控VPS库存情况，下面我们记录一下一些代码的细节片段。
这里写一下如何通过插件功能自定义某个页面的类型，前端显示时固定使用某个模板来显示。
<?php /* Plugin Name: JiLoc Test */ class PageTemplate { /** * A reference to an instance of this class. */ private static $instance; /** * The array of templates that this plugin tracks. */ protected $templates; /** * Returns an instance of this class. */ public static function get_instance() { if ( null == self::$instance ) { self::$instance = new PageTemplater(); } return self::$instance; } /** * Initializes the plugin by setting filters and administration functions. */ private function __construct() { $this->templates = array(); // Add a filter to the attributes metabox to inject template into the cache. if ( version_compare( floatval( get_bloginfo( 'version' ) ), '4.7', '<' ) ) { // 4.6 and older add_filter( 'page_attributes_dropdown_pages_args', array( $this, 'register_project_templates' ) ); } else { // Add a filter to the wp 4.7 version attributes metabox add_filter( 'theme_page_templates', array( $this, 'add_new_template' ) ); } // Add a filter to the save post to inject out template into the page cache add_filter( 'wp_insert_post_data', array( $this, 'register_project_templates' ) ); // Add a filter to the template include to determine if the page has our // template assigned and return it's path add_filter( 'template_include', array( $this, 'view_project_template') ); // Add your templates to this array. $this->templates = array( 'goodtobebad-template.php' => 'It's Good to Be Bad', ); } /** * Adds our template to the page dropdown for v4.7+ * */ public function add_new_template( $posts_templates ) { $posts_templates = array_merge( $posts_templates, $this->templates ); return $posts_templates; } /** * Adds our template to the pages cache in order to trick WordPress * into thinking the template file exists where it doens't really exist. */ public function register_project_templates( $atts ) { // Create the key used for the themes cache $cache_key = 'page_templates-' . md5( get_theme_root() . '/' . get_stylesheet() ); // Retrieve the cache list. // If it doesn't exist, or it's empty prepare an array $templates = wp_get_theme()->get_page_templates(); if ( empty( $templates ) ) { $templates = array(); } // New cache, therefore remove the old one wp_cache_delete( $cache_key , 'themes'); // Now add our template to the list of templates by merging our templates // with the existing templates array from the cache. $templates = array_merge( $templates, $this->templates ); // Add the modified cache to allow WordPress to pick it up for listing // available templates wp_cache_add( $cache_key, $templates, 'themes', 1800 ); return $atts; } /** * Checks if the template is assigned to the page */ public function view_project_template( $template ) { // Get global post global $post; // Return template if post is empty if ( ! $post ) { return $template; } // Return default template if we don't have a custom one defined if ( ! isset( $this->templates[get_post_meta( $post->ID, '_wp_page_template', true )] ) ) { return $template; } $file = plugin_dir_path( __FILE__ ). get_post_meta( $post->ID, '_wp_page_template', true ); // Just to be safe, we check if the file exist first if ( file_exists( $file ) ) { return $file; } else { echo $file; } // Return template return $template; } } add_action( 'plugins_loaded', array( 'PageTemplate', 'get_instance' ) );