jd-check-theme-activity.php

<?php
/**
 * @package jd-check-theme-activity
 * @version 1.0
 */

/*
Plugin Name: Check Theme Activity
Plugin URI: https://joseph-dickson.com
Description: Dashboard widgets that display which themes are active.
Author: Joseph Dickson
Version: 1.0
Author URI: https://joseph-dickson.com
*/

/** 
 * Adapted from https://wordpress.stackexchange.com/questions/54742/how-to-do-i-get-a-list-of-active-plugins-on-my-wordpress-blog-programmatically
 */

/**
 * ## Display Dashbord Widgets 
 *
 * Display Single Site Dashboard Widget
 */
add_action('wp_dashboard_setup', 'jd_dashboard_setup_themes');

function jd_dashboard_setup_themes() {

	// Site Active Themes
	wp_add_dashboard_widget( 'jd_active_site_themes', __( 'Active Theme' ), 'jd_active_site_themes' );

	// Network Active Themes
	if( is_multisite() ) {

		wp_add_dashboard_widget( 'jd_active_network_themes', __( 'Network Enabled Themes' ), 'jd_active_network_themes' );

	}

}

/**
 * Display Multisite Dashboard Widget
 */
add_action('wp_network_dashboard_setup', 'jd_network_dashboard_setup_themes');

function jd_network_dashboard_setup_themes() {

	// Network Active Themes
	wp_add_dashboard_widget( 'jd_active_network_themes', __( 'Network Enabled Themes' ), 'jd_active_network_themes' );

	// Sites on this Network
	wp_add_dashboard_widget( 'jd_single_site_themes', __( 'Themes Running on the Network' ), 'jd_single_site_themes' );

}

/**
 * ## Get Activated Plugin Information
 *
 * Locally Activated Themes
 */


function jd_active_site_themes() {

	$the_theme = get_option( 'template' );

	echo $the_theme;
	
}


/**
 * Network Activated Themes
 */
if( is_multisite() ) {

	function jd_active_network_themes() {

		$the_themes = wp_get_themes( array( 'allowed' => true ) );

		echo '<p>Network themes available.</p>';

		echo '<ul>';

		foreach($the_themes as $key => $value) {
			
			$string = explode('/',$key); // plugin slug will be displayed

			echo '<li>'.$string[0] .'</li>';

			}

		echo '</ul>';

	}
	
}


/**
 * Themes Activated Locally on Each Site
 */

function jd_single_site_themes() {
	global $wpdb;

	$blogs = $wpdb->get_results("
		SELECT blog_id
		FROM {$wpdb->blogs}
		WHERE site_id = '{$wpdb->siteid}'
		AND spam = '0'
		AND deleted = '0'
		AND archived = '0'
	");

	foreach ($blogs as $blog) {

		$active_theme = wp_get_theme();

		echo '<h1>' . get_blog_option($blog->blog_id, 'blogname') . '</h1>';

		echo '<p><strong>Active Theme:</strong> ' . $active_theme . '</p>';

	}

}