mainwp-hello-world-extension.php

<?php
/*
Plugin Name: MainWP Hello World! Extension
Plugin URI: https://mainwp.com
Description: MainWP Hello World! Extension is a MainWP example extension
Version: 1.1
Author: MainWP
Author URI: https://mainwp.com
Icon URI:
*/
class MainWP_Hello_World_Extension {


	public function __construct() {
		add_filter( 'mainwp_getsubpages_sites', array( &$this, 'managesites_subpage' ), 10, 1 );
        add_action( 'admin_init', array( &$this, 'admin_init' ) );
	}

    public function admin_init() {
        
    }

	public function managesites_subpage( $subPage ) {

		$subPage[] = array(
			'title'       => 'Example Extension',
			'slug'        => 'ExampleExtension',
			'sitetab'     => true,
			'menu_hidden' => true,
			'callback'    => array( static::class, 'renderPage' ),
		);

		return $subPage;
	}

	/*
	* Create your extension page
	*/

	public static function renderPage() {
		global $mainwpHelloExtensionActivator;

		// Fetch all child-sites
		$websites = apply_filters( 'mainwp_getsites', $mainwpHelloExtensionActivator->getChildFile(), $mainwpHelloExtensionActivator->getChildKey(), null );

		// Location to open on child site
		$location = 'admin.php?page=mainwp_child_tab';

		if ( is_array( $websites ) ) {
			?>      
			<div class="ui segment">
				<div class="inside">
					<p><?php _e( 'MainWP Hello World! Extension is an example extension. This extension provides two examples for calling MainWP Actions and Hooks. Purpose of this extension is to give you a start point in developing your first custom extension for the MainWP Plugin.' ); ?></p>
					<p><?php echo __( 'For more details, please visit ' ) . '<a href="http://codex.mainwp.com" target="_blank">' . __( 'MainWP Codex' ) . '</a>' . ' website.'; ?></p>
				</div>
			</div>
			<div class="ui segment">
				<h3 class="mainwp_box_title"><?php _e( 'Get Child Sites' ); ?></h3>
				<div class="inside">
					<em><?php _e( 'List all child sites and link to open the child site' ); ?></em>
					<?php
					// Display number of your child sites
					?>
					<p><?php echo __( 'Number of Child Sites: ' ) . count( $websites ); ?></p>
					<div id="mainwp_example_links">
						<?php
						// Display a list of your child site with a secure link to child site WP Admin (login not required)
						foreach ( $websites as $site ) {
							// Create link to open $location on child site
							$open_url = 'admin.php?page=SiteOpen&newWindow=yes&websiteid=' . $site['id'] . '&location=' . base64_encode( $location ) . '&_opennonce=' . wp_create_nonce( 'mainwp-admin-nonce' );
							echo $site['name'] . ': ';
							?>
							<a href="<?php echo $open_url; ?>" class="queue" target="_blank"><?php _e( 'Open location', 'mainwp' ); ?></a>.                        
							<br/>              
							<?php
						}
						?>
					</div>  
				</div>
			</div>
			
			<div class="ui segment">
				<h3 class="mainwp_box_title"><?php _e( 'Get Posts From Child Sites' ); ?></h3>
				<div class="inside">
					<em><?php _e( 'List all posts from your child site' ); ?></em>           
						<?php
						$rand_id = $websites ? wp_rand( 0, count( $websites ) - 1 ) : 0;
						$site    = $websites[ $rand_id ];
						?>
						<p><?php _e( 'Get posts from child site:' ); ?> <?php echo $site['url']; ?> <a href="admin.php?page=Extensions-Mainwp-Hello-World-Extension&siteid=<?php echo $site['id']; ?>" class="button button-primary"><?php _e( 'Click Here!' ); ?></a></p>
						<?php
						if ( isset( $_GET['siteid'] ) && ! empty( $_GET['siteid'] ) ) {
							$websiteId = $_GET['siteid'];
							// fetch information of one child-site
							$website = apply_filters( 'mainwp_getsites', $mainwpHelloExtensionActivator->getChildFile(), $mainwpHelloExtensionActivator->getChildKey(), $websiteId );
							if ( $website && is_array( $website ) ) {
								$website = current( $website );
							}

							if ( ! $website ) {
								echo '<p><strong>ERROR</strong>: ' . __( 'Child Site Not Found' ) . '</p>';
							} else {

								// Example to call function get_all_posts on child-plugin to get posts on child site
								$post_data = array(
									'status'     => 'publish',
									'maxRecords' => 10,
								);

								// hook to call the function get_all_posts
								$information = apply_filters( 'mainwp_fetchurlauthed', $mainwpHelloExtensionActivator->getChildFile(), $mainwpHelloExtensionActivator->getChildKey(), $websiteId, 'get_all_posts', $post_data );

								if ( is_array( $information ) ) {
									if ( isset( $information['error'] ) ) {
										echo '<p><strong>ERROR</strong>: ' . $information['error'] . '</p>';
									} else {
										echo '<h3>' . _( 'List of posts: ' ) . '</h3>';
										echo '<ol>';
										foreach ( $information as $post ) {
											echo '<li>';
											echo $post['title'];
											?>
																	
											<a href="<?php echo $website['url'] . ( substr( $website['url'], -1 ) != '/' ? '/' : '' ) . '?p=' . $post['id']; ?>"
												target="_blank" 
												title="View '<?php echo $post['title']; ?>'" 
												rel="permalink"><?php _e( 'View Post' ); ?></a>
											<?php
											echo '</li>';
										}
										echo '</ol>';
									}
								}
							}
						}
		} else {
				echo 'Child Sites Not Found';
		}
		?>
				</div>
			</div>
		<?php
	}
}

/*
* Activator Class is used for extension activation and deactivation
*/

class MainWP_Hello_World_Activator {

	protected $mainwpHelloExtensionActivated = false;
	protected $childEnabled                  = false;
	protected $childKey                      = false;
	protected $childFile;
	protected $plugin_handle = 'mainwp-hello-world-extension';


	public function __construct() {
		$this->childFile = __FILE__;
		add_filter( 'mainwp_getextensions', array( &$this, 'get_this_extension' ) );

		// This filter will return true if the main plugin is activated
		$this->mainwpHelloExtensionActivated = apply_filters( 'mainwp_activated_check', false );

		if ( $this->mainwpHelloExtensionActivated !== false ) {
			$this->activate_this_plugin();
		} else {
			// Because sometimes our main plugin is activated after the extension plugin is activated we also have a second step,
			// listening to the 'mainwp_activated' action. This action is triggered by MainWP after initialisation.
			add_action( 'mainwp_activated', array( &$this, 'activate_this_plugin' ) );
		}
		add_action( 'admin_notices', array( &$this, 'mainwp_error_notice' ) );
	}

	function get_this_extension( $pArray ) {
		$pArray[] = array(
			'plugin'   => __FILE__,
			'api'      => $this->plugin_handle,
			'mainwp'   => false,
			'callback' => array( &$this, 'settings' ),
		);
		return $pArray;
	}

	function settings() {
		// The "mainwp_pageheader_extensions" action is used to render the tabs on the Extensions screen.
		// It's used together with mainwp_pagefooter_extensions and mainwp_getextensions
		do_action( 'mainwp_pageheader_extensions', __FILE__ );
		if ( $this->childEnabled ) {
			MainWP_Hello_World_Extension::renderPage();
		} else {
			?>
			<div class="mainwp_info-box-yellow"><?php _e( 'The Extension has to be enabled to change the settings.' ); ?></div>
															<?php
		}
		do_action( 'mainwp_pagefooter_extensions', __FILE__ );
	}

	// The function "activate_this_plugin" is called when the main is initialized.
	function activate_this_plugin() {
		// Checking if the MainWP plugin is enabled. This filter will return true if the main plugin is activated.
		$this->mainwpHelloExtensionActivated = apply_filters( 'mainwp_activated_check', $this->mainwpHelloExtensionActivated );

		// The 'mainwp_extension_enabled_check' hook. If the plugin is not enabled this will return false,
		// if the plugin is enabled, an array will be returned containing a key.
		// This key is used for some data requests to our main
		$this->childEnabled = apply_filters( 'mainwp_extension_enabled_check', __FILE__ );

		$this->childKey = $this->childEnabled['key'];

		new MainWP_Hello_World_Extension();
	}

	function mainwp_error_notice() {
		global $current_screen;
		if ( $current_screen->parent_base == 'plugins' && $this->mainwpHelloExtensionActivated == false ) {
			echo '<div class="error"><p>MainWP Hello World! Extension ' . __( 'requires ' ) . '<a href="http://mainwp.com/" target="_blank">MainWP</a>' . __( ' Plugin to be activated in order to work. Please install and activate' ) . '<a href="http://mainwp.com/" target="_blank">MainWP</a> ' . __( 'first.' ) . '</p></div>';
		}
	}

	public function getChildKey() {
		return $this->childKey;
	}

	public function getChildFile() {
		return $this->childFile;
	}
}

global $mainwpHelloExtensionActivator;
$mainwpHelloExtensionActivator = new MainWP_Hello_World_Activator();