Ability to choose a network default theme

Author: overclokk

src/wp-admin/includes/class-wp-ms-themes-list-table.php

@@ -118,6 +118,7 @@ public function prepare_items() {
 			'disabled' => array(),
 			'upgrade'  => array(),
 			'broken'   => $this->is_site_themes ? array() : wp_get_themes( array( 'errors' => true ) ),
+			'default'  => array( wp_get_theme( WP_Theme::network_get_default_theme() ) ),
 		);
 
 		if ( $this->show_autoupdates ) {
@@ -436,6 +437,9 @@ protected function get_views() {
 						$count
 					);
 					break;
+				case 'default':
+					$text = __( 'Default' ) . ' <span class="count">(1)</span>';
+					break;
 			}
 
 			if ( $this->is_site_themes ) {
@@ -562,6 +566,7 @@ public function column_name( $theme ) {
 			'enable'  => '',
 			'disable' => '',
 			'delete'  => '',
+			'default' => '', 
 		);
 
 		$stylesheet = $theme->get_stylesheet();
@@ -949,9 +954,18 @@ public function single_row_columns( $item ) {
 						if ( $stylesheet !== $template && $item->get_stylesheet() === $stylesheet ) {
 							$active_theme_label = ' &mdash; ' . __( 'Active Child Theme' );
 						}
+
+						/* In case this is the network default theme */
+						if ( $item->get_stylesheet() === $item->network_get_default_theme() ) {
+							$active_theme_label = ' &mdash; ' . __( 'Default Theme' );
+						}
 					}
 
-					echo "<td class='theme-title column-primary{$extra_classes}'><strong>" . $item->display( 'Name' ) . $active_theme_label . '</strong>';
+					printf( "<td class='theme-title column-primary%s'><strong>%s%s</strong>",
+						$extra_classes,
+						$item->display( 'Name' ),
+						$active_theme_label
+					);
 
 					$this->column_name( $item );
 

src/wp-admin/network/themes.php

@@ -50,6 +50,11 @@
 			WP_Theme::network_disable_theme( $_GET['theme'] );
 			wp_safe_redirect( add_query_arg( 'disabled', '1', $referer ) );
 			exit;
+		case 'default':
+			check_admin_referer( 'default-theme_' . $_GET['theme'] );
+			WP_Theme::network_set_default_theme( $_GET['theme'] );
+			wp_safe_redirect( add_query_arg( 'default', '1', $referer ) );
+			exit;
 		case 'enable-selected':
 			check_admin_referer( 'bulk-themes' );
 			$themes = isset( $_POST['checked'] ) ? (array) $_POST['checked'] : array();

src/wp-includes/class-wp-theme.php

@@ -2097,6 +2097,39 @@ public static function network_disable_theme( $stylesheets ) {
 		update_site_option( 'allowedthemes', $allowed_themes );
 	}
 
+	/**
+	 * Set the network default theme.
+	 *
+	 * @since 5.0.0
+	 * @access public
+	 * @static
+	 *
+	 * @param string $stylesheet name.
+	 */
+	public static function network_set_default_theme( $stylesheet ) {
+		if ( ! is_multisite() ) {
+			return;
+		}
+
+		$theme = wp_get_theme( $stylesheet );
+		if ( ! $theme->exists() || ! $theme->is_allowed() ) {
+			return;
+		}
+
+		update_network_option( null, 'default_theme', $stylesheet );
+	}
+
+	/**
+	 * Get the network default theme.
+	 *
+	 * @since 5.0.0
+	 * @access public
+	 * @static
+	 */
+	public static function network_get_default_theme() {
+		return get_network_option( null, 'default_theme', WP_DEFAULT_THEME );
+	}
+
 	/**
 	 * Sorts themes by name.
 	 *