Make the order list sortable by the order number rather than the order ID

woocommerce-advanced-ordernumbers.php

@@ -116,6 +116,9 @@ if ( in_array( 'woocommerce/woocommerce.php', apply_filters( 'active_plugins', g
 				// The checkout page assumes all subpages are payment gateways, so we have to override this:
 				add_action( 'woocommerce_settings_checkout', array( $this, 'output' ) );
 				add_action( 'woocommerce_settings_save_checkout', array( $this, 'save' ) );
+				// Sort the order list in the backend by order number rather than ID, make sure this is called LAST so we modify the defaults passed as arguments
+				add_filter( 'manage_edit-shop_order_sortable_columns', array( $this, 'modify_order_column_sortkey' ), 9999 );
+
 
 				// register filters
 				add_filter("plugin_action_links_$plugin", array(&$this, 'plugin_settings_link'));
@@ -157,6 +160,17 @@ if ( in_array( 'woocommerce/woocommerce.php', apply_filters( 'active_plugins', g
 				$fields[] = $this->ordernumber_meta;
 				return $fields;
 			}
+			
+			/**
+			 * Sort the order list's "Order" column by our post meta rather than by ID
+			 */
+			public function modify_order_column_sortkey($columns) {
+				$custom = array(
+					'order_title' => $this->ordernumber_meta,
+				);
+				// Use the passed columns as "default", so effectively, only the order_title will be changed:
+				return wp_parse_args ($custom, $columns);
+			}
 
 			/**
 			 * Counter handling (simple loading/storing counters), storing them as options