/** * WP_Theme Class * * @package WordPress * @subpackage Theme */ final class WP_Theme implements ArrayAccess { /** * Headers for style.css files. * * @static * @access private * @var array */ private static $file_headers = array( 'Name' => 'Theme Name', 'ThemeURI' => 'Theme URI', 'Description' => 'Description', 'Author' => 'Author', 'AuthorURI' => 'Author URI', 'Version' => 'Version', 'Template' => 'Template', 'Status' => 'Status', 'Tags' => 'Tags', 'TextDomain' => 'Text Domain', 'DomainPath' => 'Domain Path', ); /** * Default themes. * * @static * @access private * @var array */ private static $default_themes = array( 'classic' => 'WordPress Classic', 'default' => 'WordPress Default', 'twentyten' => 'Twenty Ten', 'twentyeleven' => 'Twenty Eleven', 'twentytwelve' => 'Twenty Twelve', 'twentythirteen' => 'Twenty Thirteen', 'twentyfourteen' => 'Twenty Fourteen', 'twentyfifteen' => 'Twenty Fifteen', ); /** * Renamed theme tags. * * @static * @access private * @var array */ private static $tag_map = array( 'fixed-width' => 'fixed-layout', 'flexible-width' => 'fluid-layout', ); /** * Absolute path to the theme root, usually wp-content/themes * * @access private * @var string */ private $theme_root; /** * Header data from the theme's style.css file. * * @access private * @var array */ private $headers = array(); /** * Header data from the theme's style.css file after being sanitized. * * @access private * @var array */ private $headers_sanitized; /** * Header name from the theme's style.css after being translated. * * Cached due to sorting functions running over the translated name. * * @access private * @var string */ private $name_translated; /** * Errors encountered when initializing the theme. * * @access private * @var WP_Error */ private $errors; /** * The directory name of the theme's files, inside the theme root. * * In the case of a child theme, this is directory name of the child theme. * Otherwise, 'stylesheet' is the same as 'template'. * * @access private * @var string */ private $stylesheet; /** * The directory name of the theme's files, inside the theme root. * * In the case of a child theme, this is the directory name of the parent theme. * Otherwise, 'template' is the same as 'stylesheet'. * * @access private * @var string */ private $template; /** * A reference to the parent theme, in the case of a child theme. * * @access private * @var WP_Theme */ private $parent; /** * URL to the theme root, usually an absolute URL to wp-content/themes * * @access private * var string */ private $theme_root_uri; /** * Flag for whether the theme's textdomain is loaded. * * @access private * @var bool */ private $textdomain_loaded; /** * Stores an md5 hash of the theme root, to function as the cache key. * * @access private * @var string */ private $cache_hash; /** * Flag for whether the themes cache bucket should be persistently cached. * * Default is false. Can be set with the wp_cache_themes_persistently filter. * * @static * @access private * @var bool */ private static $persistently_cache; /** * Expiration time for the themes cache bucket. * * By default the bucket is not cached, so this value is useless. * * @static * @access private * @var bool */ private static $cache_expiration = 1800; /** * Constructor for WP_Theme. * * @global array $wp_theme_directories * * @param string $theme_dir Directory of the theme within the theme_root. * @param string $theme_root Theme root. * @param WP_Error|void $_child If this theme is a parent theme, the child may be passed for validation purposes. */ public function __construct( $theme_dir, $theme_root, $_child = null ) { global $wp_theme_directories; // Initialize caching on first run. if ( ! isset( self::$persistently_cache ) ) { /** This action is documented in wp-includes/theme.php */ self::$persistently_cache = apply_filters( 'wp_cache_themes_persistently', false, 'WP_Theme' ); if ( self::$persistently_cache ) { wp_cache_add_global_groups( 'themes' ); if ( is_int( self::$persistently_cache ) ) self::$cache_expiration = self::$persistently_cache; } else { wp_cache_add_non_persistent_groups( 'themes' ); } } $this->theme_root = $theme_root; $this->stylesheet = $theme_dir; // Correct a situation where the theme is 'some-directory/some-theme' but 'some-directory' was passed in as part of the theme root instead. if ( ! in_array( $theme_root, (array) $wp_theme_directories ) && in_array( dirname( $theme_root ), (array) $wp_theme_directories ) ) { $this->stylesheet = basename( $this->theme_root ) . '/' . $this->stylesheet; $this->theme_root = dirname( $theme_root ); } $this->cache_hash = md5( $this->theme_root . '/' . $this->stylesheet ); $theme_file = $this->stylesheet . '/style.css'; $cache = $this->cache_get( 'theme' ); if ( is_array( $cache ) ) { foreach ( array( 'errors', 'headers', 'template' ) as $key ) { if ( isset( $cache[ $key ] ) ) $this->$key = $cache[ $key ]; } if ( $this->errors ) return; if ( isset( $cache['theme_root_template'] ) ) $theme_root_template = $cache['theme_root_template']; } elseif ( ! file_exists( $this->theme_root . '/' . $theme_file ) ) { $this->headers['Name'] = $this->stylesheet; if ( ! file_exists( $this->theme_root . '/' . $this->stylesheet ) ) $this->errors = new WP_Error( 'theme_not_found', sprintf( __( 'The theme directory "%s" does not exist.' ), esc_html( $this->stylesheet ) ) ); else $this->errors = new WP_Error( 'theme_no_stylesheet', __( 'Stylesheet is missing.' ) ); $this->template = $this->stylesheet; $this->cache_add( 'theme', array( 'headers' => $this->headers, 'errors' => $this->errors, 'stylesheet' => $this->stylesheet, 'template' => $this->template ) ); if ( ! file_exists( $this->theme_root ) ) // Don't cache this one. $this->errors->add( 'theme_root_missing', __( 'ERROR: The themes directory is either empty or doesn’t exist. Please check your installation.' ) ); return; } elseif ( ! is_readable( $this->theme_root . '/' . $theme_file ) ) { $this->headers['Name'] = $this->stylesheet; $this->errors = new WP_Error( 'theme_stylesheet_not_readable', __( 'Stylesheet is not readable.' ) ); $this->template = $this->stylesheet; $this->cache_add( 'theme', array( 'headers' => $this->headers, 'errors' => $this->errors, 'stylesheet' => $this->stylesheet, 'template' => $this->template ) ); return; } else { $this->headers = get_file_data( $this->theme_root . '/' . $theme_file, self::$file_headers, 'theme' ); // Default themes always trump their pretenders. // Properly identify default themes that are inside a directory within wp-content/themes. if ( $default_theme_slug = array_search( $this->headers['Name'], self::$default_themes ) ) { if ( basename( $this->stylesheet ) != $default_theme_slug ) $this->headers['Name'] .= '/' . $this->stylesheet; } } // (If template is set from cache [and there are no errors], we know it's good.) if ( ! $this->template && ! ( $this->template = $this->headers['Template'] ) ) { $this->template = $this->stylesheet; if ( ! file_exists( $this->theme_root . '/' . $this->stylesheet . '/index.php' ) ) { $this->errors = new WP_Error( 'theme_no_index', __( 'Template is missing.' ) ); $this->cache_add( 'theme', array( 'headers' => $this->headers, 'errors' => $this->errors, 'stylesheet' => $this->stylesheet, 'template' => $this->template ) ); return; } } // If we got our data from cache, we can assume that 'template' is pointing to the right place. if ( ! is_array( $cache ) && $this->template != $this->stylesheet && ! file_exists( $this->theme_root . '/' . $this->template . '/index.php' ) ) { // If we're in a directory of themes inside /themes, look for the parent nearby. // wp-content/themes/directory-of-themes/* $parent_dir = dirname( $this->stylesheet ); if ( '.' != $parent_dir && file_exists( $this->theme_root . '/' . $parent_dir . '/' . $this->template . '/index.php' ) ) { $this->template = $parent_dir . '/' . $this->template; } elseif ( ( $directories = search_theme_directories() ) && isset( $directories[ $this->template ] ) ) { // Look for the template in the search_theme_directories() results, in case it is in another theme root. // We don't look into directories of themes, just the theme root. $theme_root_template = $directories[ $this->template ]['theme_root']; } else { // Parent theme is missing. $this->errors = new WP_Error( 'theme_no_parent', sprintf( __( 'The parent theme is missing. Please install the "%s" parent theme.' ), esc_html( $this->template ) ) ); $this->cache_add( 'theme', array( 'headers' => $this->headers, 'errors' => $this->errors, 'stylesheet' => $this->stylesheet, 'template' => $this->template ) ); $this->parent = new WP_Theme( $this->template, $this->theme_root, $this ); return; } } // Set the parent, if we're a child theme. if ( $this->template != $this->stylesheet ) { // If we are a parent, then there is a problem. Only two generations allowed! Cancel things out. if ( $_child instanceof WP_Theme && $_child->template == $this->stylesheet ) { $_child->parent = null; $_child->errors = new WP_Error( 'theme_parent_invalid', sprintf( __( 'The "%s" theme is not a valid parent theme.' ), esc_html( $_child->template ) ) ); $_child->cache_add( 'theme', array( 'headers' => $_child->headers, 'errors' => $_child->errors, 'stylesheet' => $_child->stylesheet, 'template' => $_child->template ) ); // The two themes actually reference each other with the Template header. if ( $_child->stylesheet == $this->template ) { $this->errors = new WP_Error( 'theme_parent_invalid', sprintf( __( 'The "%s" theme is not a valid parent theme.' ), esc_html( $this->template ) ) ); $this->cache_add( 'theme', array( 'headers' => $this->headers, 'errors' => $this->errors, 'stylesheet' => $this->stylesheet, 'template' => $this->template ) ); } return; } // Set the parent. Pass the current instance so we can do the crazy checks above and assess errors. $this->parent = new WP_Theme( $this->template, isset( $theme_root_template ) ? $theme_root_template : $this->theme_root, $this ); } // We're good. If we didn't retrieve from cache, set it. if ( ! is_array( $cache ) ) { $cache = array( 'headers' => $this->headers, 'errors' => $this->errors, 'stylesheet' => $this->stylesheet, 'template' => $this->template ); // If the parent theme is in another root, we'll want to cache this. Avoids an entire branch of filesystem calls above. if ( isset( $theme_root_template ) ) $cache['theme_root_template'] = $theme_root_template; $this->cache_add( 'theme', $cache ); } } /** * When converting the object to a string, the theme name is returned. * * @return string Theme name, ready for display (translated) */ public function __toString() { return (string) $this->display('Name'); } /** * __isset() magic method for properties formerly returned by current_theme_info() * * @staticvar array $properties * * @return bool */ public function __isset( $offset ) { static $properties = array( 'name', 'title', 'version', 'parent_theme', 'template_dir', 'stylesheet_dir', 'template', 'stylesheet', 'screenshot', 'description', 'author', 'tags', 'theme_root', 'theme_root_uri', ); return in_array( $offset, $properties ); } /** * __get() magic method for properties formerly returned by current_theme_info() * * @return mixed */ public function __get( $offset ) { switch ( $offset ) { case 'name' : case 'title' : return $this->get('Name'); case 'version' : return $this->get('Version'); case 'parent_theme' : return $this->parent() ? $this->parent()->get('Name') : ''; case 'template_dir' : return $this->get_template_directory(); case 'stylesheet_dir' : return $this->get_stylesheet_directory(); case 'template' : return $this->get_template(); case 'stylesheet' : return $this->get_stylesheet(); case 'screenshot' : return $this->get_screenshot( 'relative' ); // 'author' and 'description' did not previously return translated data. case 'description' : return $this->display('Description'); case 'author' : return $this->display('Author'); case 'tags' : return $this->get( 'Tags' ); case 'theme_root' : return $this->get_theme_root(); case 'theme_root_uri' : return $this->get_theme_root_uri(); // For cases where the array was converted to an object. default : return $this->offsetGet( $offset ); } } /** * Method to implement ArrayAccess for keys formerly returned by get_themes() * * @param mixed $offset * @param mixed $value */ public function offsetSet( $offset, $value ) {} /** * Method to implement ArrayAccess for keys formerly returned by get_themes() * * @param mixed $offset */ public function offsetUnset( $offset ) {} /** * Method to implement ArrayAccess for keys formerly returned by get_themes() * * @staticvar array $keys * * @param mixed $offset * @return bool */ public function offsetExists( $offset ) { static $keys = array( 'Name', 'Version', 'Status', 'Title', 'Author', 'Author Name', 'Author URI', 'Description', 'Template', 'Stylesheet', 'Template Files', 'Stylesheet Files', 'Template Dir', 'Stylesheet Dir', 'Screenshot', 'Tags', 'Theme Root', 'Theme Root URI', 'Parent Theme', ); return in_array( $offset, $keys ); } /** * Method to implement ArrayAccess for keys formerly returned by get_themes(). * * Author, Author Name, Author URI, and Description did not previously return * translated data. We are doing so now as it is safe to do. However, as * Name and Title could have been used as the key for get_themes(), both remain * untranslated for back compatibility. This means that ['Name'] is not ideal, * and care should be taken to use $theme->display('Name') to get a properly * translated header. * * @param mixed $offset * @return mixed */ public function offsetGet( $offset ) { switch ( $offset ) { case 'Name' : case 'Title' : // See note above about using translated data. get() is not ideal. // It is only for backwards compatibility. Use display(). return $this->get('Name'); case 'Author' : return $this->display( 'Author'); case 'Author Name' : return $this->display( 'Author', false); case 'Author URI' : return $this->display('AuthorURI'); case 'Description' : return $this->display( 'Description'); case 'Version' : case 'Status' : return $this->get( $offset ); case 'Template' : return $this->get_template(); case 'Stylesheet' : return $this->get_stylesheet(); case 'Template Files' : return $this->get_files( 'php', 1, true ); case 'Stylesheet Files' : return $this->get_files( 'css', 0, false ); case 'Template Dir' : return $this->get_template_directory(); case 'Stylesheet Dir' : return $this->get_stylesheet_directory(); case 'Screenshot' : return $this->get_screenshot( 'relative' ); case 'Tags' : return $this->get('Tags'); case 'Theme Root' : return $this->get_theme_root(); case 'Theme Root URI' : return $this->get_theme_root_uri(); case 'Parent Theme' : return $this->parent() ? $this->parent()->get('Name') : ''; default : return null; } } /** * Returns errors property. * * @since 3.4.0 * @access public * * @return WP_Error|false WP_Error if there are errors, or false. */ public function errors() { return is_wp_error( $this->errors ) ? $this->errors : false; } /** * Whether the theme exists. * * A theme with errors exists. A theme with the error of 'theme_not_found', * meaning that the theme's directory was not found, does not exist. * * @since 3.4.0 * @access public * * @return bool Whether the theme exists. */ public function exists() { return ! ( $this->errors() && in_array( 'theme_not_found', $this->errors()->get_error_codes() ) ); } /** * Returns reference to the parent theme. * * @since 3.4.0 * @access public * * @return WP_Theme|false Parent theme, or false if the current theme is not a child theme. */ public function parent() { return isset( $this->parent ) ? $this->parent : false; } /** * Adds theme data to cache. * * Cache entries keyed by the theme and the type of data. * * @since 3.4.0 * @access private * * @param string $key Type of data to store (theme, screenshot, headers, page_templates) * @param string $data Data to store * @return bool Return value from wp_cache_add() */ private function cache_add( $key, $data ) { return wp_cache_add( $key . '-' . $this->cache_hash, $data, 'themes', self::$cache_expiration ); } /** * Gets theme data from cache. * * Cache entries are keyed by the theme and the type of data. * * @since 3.4.0 * @access private * * @param string $key Type of data to retrieve (theme, screenshot, headers, page_templates) * @return mixed Retrieved data */ private function cache_get( $key ) { return wp_cache_get( $key . '-' . $this->cache_hash, 'themes' ); } /** * Clears the cache for the theme. * * @since 3.4.0 * @access public */ public function cache_delete() { foreach ( array( 'theme', 'screenshot', 'headers', 'page_templates' ) as $key ) wp_cache_delete( $key . '-' . $this->cache_hash, 'themes' ); $this->template = $this->textdomain_loaded = $this->theme_root_uri = $this->parent = $this->errors = $this->headers_sanitized = $this->name_translated = null; $this->headers = array(); $this->__construct( $this->stylesheet, $this->theme_root ); } /** * Get a raw, unformatted theme header. * * The header is sanitized, but is not translated, and is not marked up for display. * To get a theme header for display, use the display() method. * * Use the get_template() method, not the 'Template' header, for finding the template. * The 'Template' header is only good for what was written in the style.css, while * get_template() takes into account where WordPress actually located the theme and * whether it is actually valid. * * @since 3.4.0 * @access public * * @param string $header Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags. * @return string|false String on success, false on failure. */ public function get( $header ) { if ( ! isset( $this->headers[ $header ] ) ) return false; if ( ! isset( $this->headers_sanitized ) ) { $this->headers_sanitized = $this->cache_get( 'headers' ); if ( ! is_array( $this->headers_sanitized ) ) $this->headers_sanitized = array(); } if ( isset( $this->headers_sanitized[ $header ] ) ) return $this->headers_sanitized[ $header ]; // If themes are a persistent group, sanitize everything and cache it. One cache add is better than many cache sets. if ( self::$persistently_cache ) { foreach ( array_keys( $this->headers ) as $_header ) $this->headers_sanitized[ $_header ] = $this->sanitize_header( $_header, $this->headers[ $_header ] ); $this->cache_add( 'headers', $this->headers_sanitized ); } else { $this->headers_sanitized[ $header ] = $this->sanitize_header( $header, $this->headers[ $header ] ); } return $this->headers_sanitized[ $header ]; } /** * Gets a theme header, formatted and translated for display. * * @since 3.4.0 * @access public * * @param string $header Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags. * @param bool $markup Optional. Whether to mark up the header. Defaults to true. * @param bool $translate Optional. Whether to translate the header. Defaults to true. * @return string|false Processed header, false on failure. */ public function display( $header, $markup = true, $translate = true ) { $value = $this->get( $header ); if ( false === $value ) { return false; } if ( $translate && ( empty( $value ) || ! $this->load_textdomain() ) ) $translate = false; if ( $translate ) $value = $this->translate_header( $header, $value ); if ( $markup ) $value = $this->markup_header( $header, $value, $translate ); return $value; } /** * Sanitize a theme header. * * @since 3.4.0 * @access private * * @staticvar array $header_tags * @staticvar array $header_tags_with_a * * @param string $header Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags. * @param string $value Value to sanitize. * @return mixed */ private function sanitize_header( $header, $value ) { switch ( $header ) { case 'Status' : if ( ! $value ) { $value = 'publish'; break; } // Fall through otherwise. case 'Name' : static $header_tags = array( 'abbr' => array( 'title' => true ), 'acronym' => array( 'title' => true ), 'code' => true, 'em' => true, 'strong' => true, ); $value = wp_kses( $value, $header_tags ); break; case 'Author' : // There shouldn't be anchor tags in Author, but some themes like to be challenging. case 'Description' : static $header_tags_with_a = array( 'a' => array( 'href' => true, 'title' => true ), 'abbr' => array( 'title' => true ), 'acronym' => array( 'title' => true ), 'code' => true, 'em' => true, 'strong' => true, ); $value = wp_kses( $value, $header_tags_with_a ); break; case 'ThemeURI' : case 'AuthorURI' : $value = esc_url_raw( $value ); break; case 'Tags' : $value = array_filter( array_map( 'trim', explode( ',', strip_tags( $value ) ) ) ); break; case 'Version' : $value = strip_tags( $value ); break; } return $value; } /** * Mark up a theme header. * * @since 3.4.0 * @access private * * @staticvar string $comma * * @param string $header Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags. * @param string $value Value to mark up. * @param string $translate Whether the header has been translated. * @return string Value, marked up. */ private function markup_header( $header, $value, $translate ) { switch ( $header ) { case 'Name' : if ( empty( $value ) ) { $value = esc_html( $this->get_stylesheet() ); } break; case 'Description' : $value = wptexturize( $value ); break; case 'Author' : if ( $this->get('AuthorURI') ) { $value = sprintf( '%2$s', $this->display( 'AuthorURI', true, $translate ), $value ); } elseif ( ! $value ) { $value = __( 'Anonymous' ); } break; case 'Tags' : static $comma = null; if ( ! isset( $comma ) ) { /* translators: used between list items, there is a space after the comma */ $comma = __( ', ' ); } $value = implode( $comma, $value ); break; case 'ThemeURI' : case 'AuthorURI' : $value = esc_url( $value ); break; } return $value; } /** * Translate a theme header. * * @since 3.4.0 * @access private * * @staticvar array $tags_list * * @param string $header Theme header. Name, Description, Author, Version, ThemeURI, AuthorURI, Status, Tags. * @param string $value Value to translate. * @return string Translated value. */ private function translate_header( $header, $value ) { switch ( $header ) { case 'Name' : // Cached for sorting reasons. if ( isset( $this->name_translated ) ) return $this->name_translated; $this->name_translated = translate( $value, $this->get('TextDomain' ) ); return $this->name_translated; case 'Tags' : if ( empty( $value ) || ! function_exists( 'get_theme_feature_list' ) ) return $value; static $tags_list; if ( ! isset( $tags_list ) ) { $tags_list = array(); $feature_list = get_theme_feature_list( false ); // No API foreach ( $feature_list as $tags ) $tags_list += $tags; } foreach ( $value as &$tag ) { if ( isset( $tags_list[ $tag ] ) ) { $tag = $tags_list[ $tag ]; } elseif ( isset( self::$tag_map[ $tag ] ) ) { $tag = $tags_list[ self::$tag_map[ $tag ] ]; } } return $value; default : $value = translate( $value, $this->get('TextDomain') ); } return $value; } /** * The directory name of the theme's "stylesheet" files, inside the theme root. * * In the case of a child theme, this is directory name of the child theme. * Otherwise, get_stylesheet() is the same as get_template(). * * @since 3.4.0 * @access public * * @return string Stylesheet */ public function get_stylesheet() { return $this->stylesheet; } /** * The directory name of the theme's "template" files, inside the theme root. * * In the case of a child theme, this is the directory name of the parent theme. * Otherwise, the get_template() is the same as get_stylesheet(). * * @since 3.4.0 * @access public * * @return string Template */ public function get_template() { return $this->template; } /** * Returns the absolute path to the directory of a theme's "stylesheet" files. * * In the case of a child theme, this is the absolute path to the directory * of the child theme's files. * * @since 3.4.0 * @access public * * @return string Absolute path of the stylesheet directory. */ public function get_stylesheet_directory() { if ( $this->errors() && in_array( 'theme_root_missing', $this->errors()->get_error_codes() ) ) return ''; return $this->theme_root . '/' . $this->stylesheet; } /** * Returns the absolute path to the directory of a theme's "template" files. * * In the case of a child theme, this is the absolute path to the directory * of the parent theme's files. * * @since 3.4.0 * @access public * * @return string Absolute path of the template directory. */ public function get_template_directory() { if ( $this->parent() ) $theme_root = $this->parent()->theme_root; else $theme_root = $this->theme_root; return $theme_root . '/' . $this->template; } /** * Returns the URL to the directory of a theme's "stylesheet" files. * * In the case of a child theme, this is the URL to the directory of the * child theme's files. * * @since 3.4.0 * @access public * * @return string URL to the stylesheet directory. */ public function get_stylesheet_directory_uri() { return $this->get_theme_root_uri() . '/' . str_replace( '%2F', '/', rawurlencode( $this->stylesheet ) ); } /** * Returns the URL to the directory of a theme's "template" files. * * In the case of a child theme, this is the URL to the directory of the * parent theme's files. * * @since 3.4.0 * @access public * * @return string URL to the template directory. */ public function get_template_directory_uri() { if ( $this->parent() ) $theme_root_uri = $this->parent()->get_theme_root_uri(); else $theme_root_uri = $this->get_theme_root_uri(); return $theme_root_uri . '/' . str_replace( '%2F', '/', rawurlencode( $this->template ) ); } /** * The absolute path to the directory of the theme root. * * This is typically the absolute path to wp-content/themes. * * @since 3.4.0 * @access public * * @return string Theme root. */ public function get_theme_root() { return $this->theme_root; } /** * Returns the URL to the directory of the theme root. * * This is typically the absolute URL to wp-content/themes. This forms the basis * for all other URLs returned by WP_Theme, so we pass it to the public function * get_theme_root_uri() and allow it to run the theme_root_uri filter. * * @since 3.4.0 * @access public * * @return string Theme root URI. */ public function get_theme_root_uri() { if ( ! isset( $this->theme_root_uri ) ) $this->theme_root_uri = get_theme_root_uri( $this->stylesheet, $this->theme_root ); return $this->theme_root_uri; } /** * Returns the main screenshot file for the theme. * * The main screenshot is called screenshot.png. gif and jpg extensions are also allowed. * * Screenshots for a theme must be in the stylesheet directory. (In the case of child * themes, parent theme screenshots are not inherited.) * * @since 3.4.0 * @access public * * @param string $uri Type of URL to return, either 'relative' or an absolute URI. Defaults to absolute URI. * @return string|false Screenshot file. False if the theme does not have a screenshot. */ public function get_screenshot( $uri = 'uri' ) { $screenshot = $this->cache_get( 'screenshot' ); if ( $screenshot ) { if ( 'relative' == $uri ) return $screenshot; return $this->get_stylesheet_directory_uri() . '/' . $screenshot; } elseif ( 0 === $screenshot ) { return false; } foreach ( array( 'png', 'gif', 'jpg', 'jpeg' ) as $ext ) { if ( file_exists( $this->get_stylesheet_directory() . "/screenshot.$ext" ) ) { $this->cache_add( 'screenshot', 'screenshot.' . $ext ); if ( 'relative' == $uri ) return 'screenshot.' . $ext; return $this->get_stylesheet_directory_uri() . '/' . 'screenshot.' . $ext; } } $this->cache_add( 'screenshot', 0 ); return false; } /** * Return files in the theme's directory. * * @since 3.4.0 * @access public * * @param mixed $type Optional. Array of extensions to return. Defaults to all files (null). * @param int $depth Optional. How deep to search for files. Defaults to a flat scan (0 depth). -1 depth is infinite. * @param bool $search_parent Optional. Whether to return parent files. Defaults to false. * @return array Array of files, keyed by the path to the file relative to the theme's directory, with the values * being absolute paths. */ public function get_files( $type = null, $depth = 0, $search_parent = false ) { $files = (array) self::scandir( $this->get_stylesheet_directory(), $type, $depth ); if ( $search_parent && $this->parent() ) $files += (array) self::scandir( $this->get_template_directory(), $type, $depth ); return $files; } /** * Returns the theme's page templates. * * @since 3.4.0 * @access public * * @param WP_Post|null $post Optional. The post being edited, provided for context. * @return array Array of page templates, keyed by filename, with the value of the translated header name. */ public function get_page_templates( $post = null ) { // If you screw up your current theme and we invalidate your parent, most things still work. Let it slide. if ( $this->errors() && $this->errors()->get_error_codes() !== array( 'theme_parent_invalid' ) ) return array(); $page_templates = $this->cache_get( 'page_templates' ); if ( ! is_array( $page_templates ) ) { $page_templates = array(); $files = (array) $this->get_files( 'php', 1 ); foreach ( $files as $file => $full_path ) { if ( ! preg_match( '|Template Name:(.*)$|mi', file_get_contents( $full_path ), $header ) ) continue; $page_templates[ $file ] = _cleanup_header_comment( $header[1] ); } $this->cache_add( 'page_templates', $page_templates ); } if ( $this->load_textdomain() ) { foreach ( $page_templates as &$page_template ) { $page_template = $this->translate_header( 'Template Name', $page_template ); } } if ( $this->parent() ) $page_templates += $this->parent()->get_page_templates( $post ); /** * Filter list of page templates for a theme. * * This filter does not currently allow for page templates to be added. * * @since 3.9.0 * * @param array $page_templates Array of page templates. Keys are filenames, * values are translated names. * @param WP_Theme $this The theme object. * @param WP_Post|null $post The post being edited, provided for context, or null. */ $return = apply_filters( 'theme_page_templates', $page_templates, $this, $post ); return array_intersect_assoc( $return, $page_templates ); } /** * Scans a directory for files of a certain extension. * * @since 3.4.0 * * @static * @access private * * @param string $path Absolute path to search. * @param array|string|null $extensions Optional. Array of extensions to find, string of a single extension, * or null for all extensions. Default null. * @param int $depth Optional. How many levels deep to search for files. Accepts 0, 1+, or * -1 (infinite depth). Default 0. * @param string $relative_path Optional. The basename of the absolute path. Used to control the * returned path for the found files, particularly when this function * recurses to lower depths. Default empty. * @return array|false Array of files, keyed by the path to the file relative to the `$path` directory prepended * with `$relative_path`, with the values being absolute paths. False otherwise. */ private static function scandir( $path, $extensions = null, $depth = 0, $relative_path = '' ) { if ( ! is_dir( $path ) ) return false; if ( $extensions ) { $extensions = (array) $extensions; $_extensions = implode( '|', $extensions ); } $relative_path = trailingslashit( $relative_path ); if ( '/' == $relative_path ) $relative_path = ''; $results = scandir( $path ); $files = array(); foreach ( $results as $result ) { if ( '.' == $result[0] ) continue; if ( is_dir( $path . '/' . $result ) ) { if ( ! $depth || 'CVS' == $result ) continue; $found = self::scandir( $path . '/' . $result, $extensions, $depth - 1 , $relative_path . $result ); $files = array_merge_recursive( $files, $found ); } elseif ( ! $extensions || preg_match( '~\.(' . $_extensions . ')$~', $result ) ) { $files[ $relative_path . $result ] = $path . '/' . $result; } } return $files; } /** * Loads the theme's textdomain. * * Translation files are not inherited from the parent theme. Todo: if this fails for the * child theme, it should probably try to load the parent theme's translations. * * @since 3.4.0 * @access public * * @return bool True if the textdomain was successfully loaded or has already been loaded. * False if no textdomain was specified in the file headers, or if the domain could not be loaded. */ public function load_textdomain() { if ( isset( $this->textdomain_loaded ) ) return $this->textdomain_loaded; $textdomain = $this->get('TextDomain'); if ( ! $textdomain ) { $this->textdomain_loaded = false; return false; } if ( is_textdomain_loaded( $textdomain ) ) { $this->textdomain_loaded = true; return true; } $path = $this->get_stylesheet_directory(); if ( $domainpath = $this->get('DomainPath') ) $path .= $domainpath; else $path .= '/languages'; $this->textdomain_loaded = load_theme_textdomain( $textdomain, $path ); return $this->textdomain_loaded; } /** * Whether the theme is allowed (multisite only). * * @since 3.4.0 * @access public * * @param string $check Optional. Whether to check only the 'network'-wide settings, the 'site' * settings, or 'both'. Defaults to 'both'. * @param int $blog_id Optional. Ignored if only network-wide settings are checked. Defaults to current blog. * @return bool Whether the theme is allowed for the network. Returns true in single-site. */ public function is_allowed( $check = 'both', $blog_id = null ) { if ( ! is_multisite() ) return true; if ( 'both' == $check || 'network' == $check ) { $allowed = self::get_allowed_on_network(); if ( ! empty( $allowed[ $this->get_stylesheet() ] ) ) return true; } if ( 'both' == $check || 'site' == $check ) { $allowed = self::get_allowed_on_site( $blog_id ); if ( ! empty( $allowed[ $this->get_stylesheet() ] ) ) return true; } return false; } /** * Returns array of stylesheet names of themes allowed on the site or network. * * @since 3.4.0 * * @static * @access public * * @param int $blog_id Optional. Defaults to current blog. * @return array Array of stylesheet names. */ public static function get_allowed( $blog_id = null ) { /** * Filter the array of themes allowed on the site or network. * * @since MU * * @param array $allowed_themes An array of theme stylesheet names. */ $network = (array) apply_filters( 'allowed_themes', self::get_allowed_on_network() ); return $network + self::get_allowed_on_site( $blog_id ); } /** * Returns array of stylesheet names of themes allowed on the network. * * @since 3.4.0 * * @static * @access public * * @staticvar array $allowed_themes * * @return array Array of stylesheet names. */ public static function get_allowed_on_network() { static $allowed_themes; if ( ! isset( $allowed_themes ) ) $allowed_themes = (array) get_site_option( 'allowedthemes' ); return $allowed_themes; } /** * Returns array of stylesheet names of themes allowed on the site. * * @since 3.4.0 * * @static * @access public * * @staticvar array $allowed_themes * * @param int $blog_id Optional. Defaults to current blog. * @return array Array of stylesheet names. */ public static function get_allowed_on_site( $blog_id = null ) { static $allowed_themes = array(); if ( ! $blog_id || ! is_multisite() ) $blog_id = get_current_blog_id(); if ( isset( $allowed_themes[ $blog_id ] ) ) return $allowed_themes[ $blog_id ]; $current = $blog_id == get_current_blog_id(); if ( $current ) { $allowed_themes[ $blog_id ] = get_option( 'allowedthemes' ); } else { switch_to_blog( $blog_id ); $allowed_themes[ $blog_id ] = get_option( 'allowedthemes' ); restore_current_blog(); } // This is all super old MU back compat joy. // 'allowedthemes' keys things by stylesheet. 'allowed_themes' keyed things by name. if ( false === $allowed_themes[ $blog_id ] ) { if ( $current ) { $allowed_themes[ $blog_id ] = get_option( 'allowed_themes' ); } else { switch_to_blog( $blog_id ); $allowed_themes[ $blog_id ] = get_option( 'allowed_themes' ); restore_current_blog(); } if ( ! is_array( $allowed_themes[ $blog_id ] ) || empty( $allowed_themes[ $blog_id ] ) ) { $allowed_themes[ $blog_id ] = array(); } else { $converted = array(); $themes = wp_get_themes(); foreach ( $themes as $stylesheet => $theme_data ) { if ( isset( $allowed_themes[ $blog_id ][ $theme_data->get('Name') ] ) ) $converted[ $stylesheet ] = true; } $allowed_themes[ $blog_id ] = $converted; } // Set the option so we never have to go through this pain again. if ( is_admin() && $allowed_themes[ $blog_id ] ) { if ( $current ) { update_option( 'allowedthemes', $allowed_themes[ $blog_id ] ); delete_option( 'allowed_themes' ); } else { switch_to_blog( $blog_id ); update_option( 'allowedthemes', $allowed_themes[ $blog_id ] ); delete_option( 'allowed_themes' ); restore_current_blog(); } } } return (array) $allowed_themes[ $blog_id ]; } /** * Sort themes by name. * * @since 3.4.0 * * @static * @access public */ public static function sort_by_name( &$themes ) { if ( 0 === strpos( get_locale(), 'en_' ) ) { uasort( $themes, array( 'WP_Theme', '_name_sort' ) ); } else { uasort( $themes, array( 'WP_Theme', '_name_sort_i18n' ) ); } } /** * Callback function for usort() to naturally sort themes by name. * * Accesses the Name header directly from the class for maximum speed. * Would choke on HTML but we don't care enough to slow it down with strip_tags(). * * @since 3.4.0 * * @static * @access private * * @return int */ private static function _name_sort( $a, $b ) { return strnatcasecmp( $a->headers['Name'], $b->headers['Name'] ); } /** * Name sort (with translation). * * @since 3.4.0 * * @static * @access private * * @return int */ private static function _name_sort_i18n( $a, $b ) { // Don't mark up; Do translate. return strnatcasecmp( $a->display( 'Name', false, true ), $b->display( 'Name', false, true ) ); } } onload事件以及DOMReady事件兼容方案 》 html5jscss

onload事件以及DOMReady事件兼容方案

曾经刚做前端时,再加上浏览器对js兼容性很不熟悉,所以很长一段时间都是用jquery,写一些简单的交互效果快速而绚丽。其中$(document).ready(function(){ ... });是在所有js代码前首先会写的,只知道这个方法是对onload事件的替代方法,当时在我心中就是将onload等于jquery的ready事件的,后来才知道它们是两个不同的事件,JQ的ready事件比onload相应的时间更早,在JQ的ready事件在DOM树渲染完成时就立即执行了,而原生JS中的onload事件是等到页面中的所有元素接收完数据后再去执行,还有一点就是在各个浏览器中还有一些不同之处。

window.onload 与 document.body.onload 事件及 BODY 标签内的内联 onload 事件三者的关系

window.onload 与 document.body.onload事件在各个浏览器中都是存在的,document.onload确是不存在的,虽然document.onload似乎是我们想要的。

在不同浏览器中window.onload 与 document.body.onload事件还存在一些差异性,实例代码如下:

<button onclick="alert(document.body.onload);">查看本页 document.body.onload 事件</button>
<button onclick="alert(window.onload);">查看本页 window.onload 事件</button>
<button onclick="alert(window.onload===document.body.onload);">查看document.body.onload 事件与 window.onload 事件是否为同一事件</button>
<script>
    document.body.onload = function (){ // 函数 A
        document.getElementById("A").innerHTML = "document.body.onload 被触发";
    };
    window.onload = function (){ // 函数 B
        document.getElementById("B").innerHTML = "window.onload 被触发";
    };
</script>
<span id="A" style="background:gold"></span>
<span id="B" style="background:gray"></span>
        
window.onload 与 document.body.onload事件

复制以上代码在各个浏览器内运行查看实际效果,将函数A和函数B调换查看函数覆盖效果。得到如下结论:

  • 在IE6、7、8中:即使在定义了 window.onload 事件函数,也会是 null ,但是window.onload 事件函数的事件处理函数始终为 document.body.onload 提供。
  • 在 Firefox 中:window.onload 事件与 document.body.onload 事件是不同的,所以后者事件函数永远不会覆盖前者。
  • 在Chrome/Safari/Opera/中:window.onload 事件与 document.body.onload 事件是相同的,所以后者事件函数会覆盖前者。

那么BODY 标签内的内联 onload 事件跟他们又是什么关系么?如下实例代码:

<script>
    window.onload=function(){
        alert("window onload");
    }
</script>
<body onload="alert('inline window onload')">
</body>
        
BODY标签内 onload 事件与 window.onload 事件

在所有浏览器中都是后者的事件函数,所以就能说明BODY标签内 onload 事件与 window.onload 事件是同一事件处理机制。

为什么很多javascript书籍里只见到window.onload没见到document.body.onload 事件呢?我猜大概是因为如果将document.body.onload提到head里,会出现document.body is null的提示错误,就像元素元素没找一样。

所以很多javascript书籍里的事例代码都是用window.onload不用document.body.onload 来说明实例,可能怕初学者刚学习就遇到这么个错误而影响javascript的学习~~~。在《JavaScript DOM编程艺术》有这样一段代码能让window.onload内的多个函数不被覆盖的方法:

function addload(func) {
    var old = window.onload;
    if (typeof window.onload != "function") {
        window.onload = func;
    } else {
        window.onload = function() {
            old();
            func();
        }
    }
};
// 添加运行函数
addload(aaa);
addload(bbb);
        
解决window.onload事件不被覆盖的经典方案

接下里不引入JQ我们自己写一个$(document).ready的方法。

DOMContentLoaded事件

使用DOMReady不而用window.onload事件的原因:当DOM树解析完成,再诸如图片、脚本、样式表甚至是iframe中所有资源接收完数据后后window.onload才会触发。如果页面中下载资源太多,window.onload触发程序函数要等到全部资源接收完数据后才会执行,如果用户点击选项卡之类的就会没反应,比较影响用户体验。但是在现代浏览器增加了DOMContentLoaded事件,它是在当DOM树解析完成就触发的,所以这就是我们想要的,但是在IE6/7/8没有此事件,所以接下来就是关于该事件的兼容新方案问题展开研究。

主流框架中DOMContentLoaded事件的实现这样转载文章中,就介绍了各大主流框架DOMContentLoaded事件的实现代码和思路,觉得不错就转载过来,我也就可以不啰嗦了。

看了上篇文章回来,我们知道解决各大Js框架中针对IE6/7/8的DOMContentLoaded兼容性方案,如下:

在readyState

  1. readyState:监听document的onreadystatechange事件,各大JS框架都是监听readyState”complete”或”loaded”,而不知此时虽然是在资源接收完数据之前,但是这已经在资源发送请求之后了。
  2. 加入script:document.write在页面加入defer属性的<script>(defer属性的<script>能延迟加载js),此方法是监听script的readyState状态,但是defer属性的<script>在IE浏览器中的实现方式有差异,特别是在页面还有iframe时。
  3. doScroll :微软文档指出doScroll在DOM结构稳定后能够访问。

标准的onreadystatechange应该有五种状态:”uninitalized”(未初始化)、”loading”(加载)、”interactive”(交互)、”complete” (完成)、”loaded”(加载完毕),document.readyState属性已被大部分浏览器支持,但是属性的在IE6/7/8中之间有细微差别。IE7/8能保证最后一个是“loaded”状态,但是IE6会因为脚本的载入顺序不同导致“loaded”和“complete”不一定是最后一个状态。所以我们通过doScroll判断DOM是否准备完毕。下面会说到为什么要使用setTimeout()来调用函数的理由

综上所诉及对现在浏览器的情况,我们对DOMReady代码采用以下几点思路:

  • 除了IE6/7/8就使用doScroll方法,对于各大JS框架现在还对低版本的wibkit采取hack,我觉得已经没必要了,wibkit不支持DOMContentLoaded 事件是07年的事了。
  • 在DOMContentLoaded事件触发之前调用push(fn),所有的fn将被push到一个数组队列中;当 DOMContentLoaded 事件触发时,按顺序执行。
  • 因为IE9以上支持addEventListener事件模型,所以就可以利用这个函数将IE6/7/8跟其他其他支持DOMContentLoaded事件事件的浏览器分开。
  • IE6/7/8利用定时器不断的去检查doScroll方法是否可以使用,为了代码的高效性,bind()只能执行一次,所以如果执行bind()就立即返回。
  • 因为javascript是单线程机制的语言,如果同一时间内有其他代码需要运行的话,则这些代码需要等到javascript引擎执行完当前代码之后才有执行机会,所以使用setTimeout()将这个耗性能的操作推迟执行,让出javascript引擎里处理其他队列中的事件,一旦等javascript引擎空闲了,就会尽快的执行,所谓的尽快是因为setTimeout()中的第二个参数是0,0不代表0ms后就执行了,这个取决于系统&&浏览器最快值(依稀记得苹果系统比windows系统这个最快值要小,浏览器的话应该IE是最慢的吧)。

所以最后的DOMReady程序如下:

var DOM = (function(){
    var readyBound = false;
    var _DOM = {
        fn: [],
        bReady : false,
        /**
         * 注册 DOM ready时的处理函数
         */
        push: function ( fn ){
            _DOM.bind();
            // 如果DOM已经准备好了 就直接调用注册的fn
            if ( _DOM.bReady ) {
                fn.call( document );
                // 否则 就将fn推入readyLis
            } else {
                _DOM.fn.push( fn );
            }
        },

        /**
         * 触发DOM ready的函数
         */
        ready: function (){
            var fn, i = 0, fns;
            _DOM.bReady = true;
            //为了减少变量查询带来的性能损耗,将fn赋值给本地变量
            fns = _DOM.fn;

            while( (fn = fns[ i++ ]) ){
                fn.call( document );
            }
            //清空
            fns = null;
        },

        /**
         * 监听 DOM ready事件
         */
        bind: function (){
            if (readyBound) return; //如果执行过bind()函数则返回
            readyBound = true;

            //如果在绑定ready的时候DOM已经准备好了,就异步调用ready函数
            if ( document.readyState === "complete" ) {
                return setTimeout( _DOM.ready,0);
            }

            if( document.addEventListener ){

                document.addEventListener( "DOMContentLoaded", function(){
                    document.removeEventListener( "DOMContentLoaded", arguments.callee, false );
                    _DOM.ready();
                }, false );


            } else {// else if( document.attachEvent )

                //使用doScroll方法来检测DOM树是否渲染完成

                var bTop = false;

                try {
                    //处于iframe中,使用doScroll方法并不代表DOM加载完毕
                    bTop = window.frameElement == null;
                } catch(e) {}


                //用bTop标识是否使用doScroll来触发ready函数
                if ( document.documentElement.doScroll && bTop ) {
                    (function(){
                        try{
                            document.documentElement.doScroll('left');
                        }catch(e){
                            return setTimeout( arguments.callee, 0 );
                        }
                        _DOM.ready();
                    })();
                }
            }
        }
    };
    return _DOM.push;
})();
        
强大而精简的DOM ready函数

这样子一个DOM ready就完成了,这个函数主体结构和代码不是我自己原创的,我只是拿来学习和分析,再加以修改,如果有错误,还望高手指点啊。

最后,我在测试时发现请求资源多的时候,后面的几个会有一段长时间的阻塞时期,后来网上搜到一篇文章说,浏览中的网络操作虽然是多个线程并行执行的,但是并行连接数是有限的,通常为 2 至 6 个。所以DOMReady虽然能让script尽可能异步执行,但是还是得保证页面中内联元素的网络请求数量。

本文源链接:http://www.html5jscss.com/domready.html

转载请注明《onload事件以及DOMReady事件兼容方案》| html5jscss

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