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tommcfarlin/00-class-meta-box.php Secret

Last active May 24, 2017
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[WordPress] Rapid Prototyping: Prototype To Code, Part 1
<?php
/**
* Registers the Meta Box with WordPress.
*
* @author Tom McFarlin
* @since 0.2.0
*/
/**
* Registers the Meta Box with WordPress. Defines the ID, title, display function,
* and the post type on which it will live.
*
* @author Tom McFarlin
* @since 0.2.0
*/
class Meta_Box {
/**
* A reference to the class that will display the contents in the meta box.
*
* @access private
* @var Meta_Box_Display
*/
private $meta_box_display;
/**
* Instantiates the class by setting its property equal to a reference to its display.
*/
public function __construct() {
$this->meta_box_display = new Meta_Box_Display();
}
/**
* The function responsible for hooking into the WordPress API.
*/
public function init() {
add_meta_box(
'three-recent-posts',
'Three Recent Posts',
array( $this->meta_box_display, 'display' ),
'post',
'side'
);
}
}
<?php
/**
* Defines the display for the meta box.
*
* @author Tom McFarlin
* @since 0.2.0
*/
/**
* Defines the display for the meta box that will render the content in the
* context of its meta box.
*
* @author Tom McFarlin
* @since 0.2.0
*/
class Meta_Box_Display {
/**
* A reference to the class that will display the contents in the meta box.
*
* @access private
* @var Post_Messenger
*/
private $messenger;
/**
* Instantiates the object by setting a property equal to that of the class
* responsible for rendering the messages from the post query.
*/
public function __construct() {
$this->messenger = new Post_Messenger( $this );
}
/**
* If there are posts to display, renders them in the metabox. Otherwise, displays
* a note that there are no posts to display.
*/
public function display( $message ) {
$this->messenger->get_message();
}
}
<?php
/**
* Display content for the meta box when requested.
*
* @author Tom McFarlin
* @since 0.2.0
*/
/**
* Retrieves information from the class responsible for querying the database and
* renders it in the context of our meta box when called via the Meta Box Display.
*
* @author Tom McFarlin
* @since 0.2.0
*/
class Post_Messenger {
/**
* A reference to the query resonsible for retrieving post information from
* the database.
*
* @access private
* @var WP_Query
*/
private $query;
/**
* A reference to the message that's displayed in the view of the
* meta box.
*
* @access private
*/
private $message;
/**
* Instantiates the class by setting a reference to the query.
*/
public function __construct() {
$this->query = new Post_Query();
}
/**
* Retrieves the content to be displayed in the meta box.
*/
public function get_message() {
$this->get_description();
if ( $this->query->has_posts() ) {
$this->get_post_message();
} else {
$this->get_no_posts_message();
}
}
/**
* Displays the description of the content of the meta box.
*
* @access private
*/
private function get_post_message() {
include_once 'post-list.php';
}
/**
* Displays the description of the content of the meta box.
*
* @access private
*/
private function get_description() {
include_once 'message-description.php';
}
/**
* Displays a message of there are no recent posts.
*
* @access private
*/
private function get_no_posts_message() {
include_once 'no-post-list.php';
}
}
<?php
/**
* Queries the database for three most recent posts.
*
* @author Tom McFarlin
* @since 0.2.0
*/
/**
* Queries the database for three most recent posts. Returns the query to the
* caller so that it can be interrogates for posts or not.
*
* @author Tom McFarlin
* @since 0.2.0
*/
class Post_Query {
/**
* A reference to the WP_Query this class wraps.
*
* @access private
* @var WP_Query
*/
private $query;
/**
* Instantiates the class by preparing instance data and executing the
* query so the display can render the contents.
*/
public function __construct() {
$this->query = null;
$this->get_posts();
}
/**
* Executes the query for returning the post recent posts ordered by date.
*
* @access private
*/
private function get_posts() {
$args = array(
'post_type' => 'post',
'post_status' => 'publish',
'orderby' => 'date',
'order' => 'desc',
);
$this->query = new WP_Query( $args );
return $this->query;
}
/**
* A helper function to determine if the query has any posts.
*/
public function has_posts() {
return ! $this->query->have_posts();
}
/**
* A helper function for retrieving the next post in the list of
* posts
*/
public function the_post() {
return $this->query->the_post();
}
}
<ol>
<?php while ( $this->query->has_posts() ) { ?>
<?php $this->query->the_post(); ?>
<li>
<a href="<?php get_the_permalink(); ?>" target="_blank">
<?php echo get_the_title(); ?>
</a>
</li>
<?php } ?>
</ol>
<p>
<span class="description">
Displays up to the three most recent posts.
</span><!-- .description -->
</p>
<p>There are no recent posts.</p>
<?php
/**
* Three Recent Posts
*
* @package TRP
* @author Tom McFarlin
* @copyright 2017 Tom McFarlin
* @license MIT
*
* @wordpress-plugin
* Plugin Name: Three Recent Posts
* Plugin URI: https://tommcfarlin.com/three-recent-posts/
* Description: Displays the three mot recent posts in your post editor screen.
* Version: 0.2.0
* Author: Tom McFarlin
* Author URI: https://tommcfarlin.com
* Text Domain: three-recent-posts
* License: GPL
* License URI: http://www.gnu.org/licenses/gpl-3.0.txt
*/
include 'class-meta-box.php';
include 'class-meta-box-display.php';
include 'class-post-messenger.php';
include 'class-post-query.php';
add_action( 'add_meta_boxes', 'trp_start' );
/**
* Starts the plugin.
*/
function trp_start() {
$meta_box = new Meta_Box();
$meta_box->init();
}
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