1. @override
dynamic onInvoke(Map<String, dynamic> params)

This is called when this node is invoked. You can return the following types from this method:

  • Iterable
  • Map
  • Table
  • Stream
  • SimpleTableResult
  • AsyncTableResult

You can also return a future that resolves to one (like if the method is async) of the following types:

  • Stream
  • Iterable
  • Map
  • Table

Source 

@override
onInvoke(Map<String, dynamic> params) {
  if (onActionInvoke != null) {
    return onActionInvoke(params);
  } else {
    return super.onInvoke(params);
  }
}