Version 5.0.0 beta 8

system/Application/Application.php

@@ -43,6 +43,7 @@ use IPS\Theme\CustomTemplate;
 use IPS\Theme\Editor\Category;
 use IPS\Theme\Editor\Setting;
 use IPS\Widget\Area;
+use IPS\Widget\Polymorphic;
 use IPS\Xml\SimpleXML;
 use OutOfRangeException;
 use OverflowException;
@@ -5287,6 +5288,27 @@ EOF;
 		return $blocks;
 	}
 
+	/**
+	 * Return a list of all valid widget keys for this application
+	 *
+	 * @return array
+	 */
+	public function getValidWidgetKeys() : array
+	{
+		$keys = [];
+		foreach( Db::i()->select( '*', 'core_widgets', [ 'app=?', $this->directory ] ) as $widget )
+		{
+			$class = 'IPS\\' . $this->directory . '\\widgets\\' . $widget['key'];
+			$keys[] = $widget['key'];
+			if( in_array( Polymorphic::class, class_implements( $class ) ) )
+			{
+				/* @var Polymorphic $class */
+				$keys = array_merge( $keys, $class::getWidgetKeys() );
+			}
+		}
+		return $keys;
+	}
+
 	/**
 	 * Cleanup after saving
 	 *