class-gamajo-template-loader.php
<?php
/**
* Template Loader for Plugins.
*
* @package Gamajo_Template_Loader
* @author Gary Jones
* @link http://github.com/GaryJones/Gamajo-Template-Loader
* @copyright 2013 Gary Jones
* @license GPL-2.0-or-later
* @version 1.3.1
*/
if ( ! class_exists( 'Gamajo_Template_Loader' ) ) {
/**
* Template loader.
*
* Originally based on functions in Easy Digital Downloads (thanks Pippin!).
*
* When using in a plugin, create a new class that extends this one and just overrides the properties.
*
* @package Gamajo_Template_Loader
* @author Gary Jones
*/
class Gamajo_Template_Loader {
/**
* Prefix for filter names.
*
* @since 1.0.0
*
* @var string
*/
protected $filter_prefix = 'your_plugin';
/**
* Directory name where custom templates for this plugin should be found in the theme.
*
* For example: 'your-plugin-templates'.
*
* @since 1.0.0
*
* @var string
*/
protected $theme_template_directory = 'plugin-templates';
/**
* Reference to the root directory path of this plugin.
*
* Can either be a defined constant, or a relative reference from where the subclass lives.
*
* e.g. YOUR_PLUGIN_TEMPLATE or plugin_dir_path( dirname( __FILE__ ) ); etc.
*
* @since 1.0.0
*
* @var string
*/
protected $plugin_directory = 'YOUR_PLUGIN_DIR';
/**
* Directory name where templates are found in this plugin.
*
* Can either be a defined constant, or a relative reference from where the subclass lives.
*
* e.g. 'templates' or 'includes/templates', etc.
*
* @since 1.1.0
*
* @var string
*/
protected $plugin_template_directory = 'templates';
/**
* Internal use only: Store located template paths.
*
* @var array
*/
private $template_path_cache = array();
/**
* Internal use only: Store variable names used for template data.
*
* Means unset_template_data() can remove all custom references from $wp_query.
*
* Initialized to contain the default 'data'.
*
* @var array
*/
private $template_data_var_names = array( 'data' );
/**
* Clean up template data.
*
* @since 1.2.0
*/
public function __destruct() {
$this->unset_template_data();
}
/**
* Retrieve a template part.
*
* @since 1.0.0
*
* @param string $slug Template slug.
* @param string $name Optional. Template variation name. Default null.
* @param bool $load Optional. Whether to load template. Default true.
* @return string
*/
public function get_template_part( $slug, $name = null, $load = true ) {
// Execute code for this part.
do_action( 'get_template_part_' . $slug, $slug, $name );
do_action( $this->filter_prefix . '_get_template_part_' . $slug, $slug, $name );
// Get files names of templates, for given slug and name.
$templates = $this->get_template_file_names( $slug, $name );
// Return the part that is found.
return $this->locate_template( $templates, $load, false );
}
/**
* Make custom data available to template.
*
* Data is available to the template as properties under the `$data` variable.
* i.e. A value provided here under `$data['foo']` is available as `$data->foo`.
*
* When an input key has a hyphen, you can use `$data->{foo-bar}` in the template.
*
* @since 1.2.0
*
* @param mixed $data Custom data for the template.
* @param string $var_name Optional. Variable under which the custom data is available in the template.
* Default is 'data'.
* @return Gamajo_Template_Loader
*/
public function set_template_data( $data, $var_name = 'data' ) {
global $wp_query;
$wp_query->query_vars[ $var_name ] = (object) $data;
// Add $var_name to custom variable store if not default value.
if ( 'data' !== $var_name ) {
$this->template_data_var_names[] = $var_name;
}
return $this;
}
/**
* Remove access to custom data in template.
*
* Good to use once the final template part has been requested.
*
* @since 1.2.0
*
* @return Gamajo_Template_Loader
*/
public function unset_template_data() {
global $wp_query;
// Remove any duplicates from the custom variable store.
$custom_var_names = array_unique( $this->template_data_var_names );
// Remove each custom data reference from $wp_query.
foreach ( $custom_var_names as $var ) {
if ( isset( $wp_query->query_vars[ $var ] ) ) {
unset( $wp_query->query_vars[ $var ] );
}
}
return $this;
}
/**
* Given a slug and optional name, create the file names of templates.
*
* @since 1.0.0
*
* @param string $slug Template slug.
* @param string $name Template variation name.
* @return array
*/
protected function get_template_file_names( $slug, $name ) {
$templates = array();
if ( isset( $name ) ) {
$templates[] = $slug . '-' . $name . '.php';
}
$templates[] = $slug . '.php';
/**
* Allow template choices to be filtered.
*
* The resulting array should be in the order of most specific first, to least specific last.
* e.g. 0 => recipe-instructions.php, 1 => recipe.php
*
* @since 1.0.0
*
* @param array $templates Names of template files that should be looked for, for given slug and name.
* @param string $slug Template slug.
* @param string $name Template variation name.
*/
return apply_filters( $this->filter_prefix . '_get_template_part', $templates, $slug, $name );
}
/**
* Retrieve the name of the highest priority template file that exists.
*
* Searches in the STYLESHEETPATH before TEMPLATEPATH so that themes which
* inherit from a parent theme can just overload one file. If the template is
* not found in either of those, it looks in the theme-compat folder last.
*
* @since 1.0.0
*
* @param string|array $template_names Template file(s) to search for, in order.
* @param bool $load If true the template file will be loaded if it is found.
* @param bool $require_once Whether to require_once or require. Default true.
* Has no effect if $load is false.
* @return string The template filename if one is located.
*/
public function locate_template( $template_names, $load = false, $require_once = true ) {
// Use $template_names as a cache key - either first element of array or the variable itself if it's a string.
$cache_key = is_array( $template_names ) ? $template_names[0] : $template_names;
// If the key is in the cache array, we've already located this file.
if ( isset( $this->template_path_cache[ $cache_key ] ) ) {
$located = $this->template_path_cache[ $cache_key ];
} else {
// No file found yet.
$located = false;
// Remove empty entries.
$template_names = array_filter( (array) $template_names );
$template_paths = $this->get_template_paths();
// Try to find a template file.
foreach ( $template_names as $template_name ) {
// Trim off any slashes from the template name.
$template_name = ltrim( $template_name, '/' );
// Try locating this template file by looping through the template paths.
foreach ( $template_paths as $template_path ) {
if ( file_exists( $template_path . $template_name ) ) {
$located = $template_path . $template_name;
// Store the template path in the cache.
$this->template_path_cache[ $cache_key ] = $located;
break 2;
}
}
}
}
if ( $load && $located ) {
load_template( $located, $require_once );
}
return $located;
}
/**
* Return a list of paths to check for template locations.
*
* Default is to check in a child theme (if relevant) before a parent theme, so that themes which inherit from a
* parent theme can just overload one file. If the template is not found in either of those, it looks in the
* theme-compat folder last.
*
* @since 1.0.0
*
* @return mixed|void
*/
protected function get_template_paths() {
$theme_directory = trailingslashit( $this->theme_template_directory );
$file_paths = array(
10 => trailingslashit( get_template_directory() ) . $theme_directory,
100 => $this->get_templates_dir(),
);
// Only add this conditionally, so non-child themes don't redundantly check active theme twice.
if ( get_stylesheet_directory() !== get_template_directory() ) {
$file_paths[1] = trailingslashit( get_stylesheet_directory() ) . $theme_directory;
}
/**
* Allow ordered list of template paths to be amended.
*
* @since 1.0.0
*
* @param array $var Default is directory in child theme at index 1, parent theme at 10, and plugin at 100.
*/
$file_paths = apply_filters( $this->filter_prefix . '_template_paths', $file_paths );
// Sort the file paths based on priority.
ksort( $file_paths, SORT_NUMERIC );
return array_map( 'trailingslashit', $file_paths );
}
/**
* Return the path to the templates directory in this plugin.
*
* May be overridden in subclass.
*
* @since 1.0.0
*
* @return string
*/
protected function get_templates_dir() {
return trailingslashit( $this->plugin_directory ) . $this->plugin_template_directory;
}
}
}