anchor.diff:      this.antialiasing = true,
       this.controllers = const [],
       this.onInit,
  -  }) : src = _Source.asset;
  +    Key? key,
  +  })  : file = null,
  +        src = _Source.asset,
  +        super(key: key);
   
     const RiveAnimation.network(
       this.name, {
  
positive.code:   asset,
    network,
    file,
  }
  
  /// The callback signature for onInit
  
negative.code: /// within it are used.
  class RiveAnimation extends StatefulWidget {
    /// The asset name or url
    final String? name;
  
    /// The Rive File object
    final RiveFile? file;
  
    /// The type of source used to retrieve the asset
    final _Source src;
  