Supabase subscribe custom action with query data type as list

I use the below custom action to pass a query data type with two fields (fieldName and fieldValue). When I add the action to the flow, I can't choose to add list items.

Could this work like when adding items to a state variable?

import 'package:supabase_flutter/supabase_flutter.dart';

Future<String> sbSubscribeToEventsQuery(
  String table,
  List<SupabaseFieldQueryStruct>? fieldsQuery, // Query conditions
  Future Function()? insertCallback,
  Future Function()? updateCallback,
  Future Function()? deleteCallback,
) async {
  try {
    final client = Supabase.instance.client;

    // Create a new channel specific to the table
    final channel = client.channel('public:$table');

    // Build the filters from fieldsQuery.fieldsQuery
    final List<PostgresChangeFilter> filters = fieldsQuery
            ?.map((filter) => PostgresChangeFilter(
                  type: PostgresChangeFilterType.eq, // Equality filter
                  column: filter.fieldName, // Column name
                  value: filter.fieldContent, // Value to match
                ))
            .toList() ??
        [];

    // Subscribe to INSERT events if the callback is provided
    if (insertCallback != null) {
      channel.onPostgresChanges(
        event: PostgresChangeEvent.insert,
        schema: 'public',
        table: table,
        filter:
            filters.isNotEmpty ? filters.first : null, // Use the first filter
        callback: (payload) async => await insertCallback(),
      );
    }

    // Subscribe to UPDATE events if the callback is provided
    if (updateCallback != null) {
      channel.onPostgresChanges(
        event: PostgresChangeEvent.update,
        schema: 'public',
        table: table,
        filter:
            filters.isNotEmpty ? filters.first : null, // Use the first filter
        callback: (payload) async => await updateCallback(),
      );
    }

    // Subscribe to DELETE events if the callback is provided
    if (deleteCallback != null) {
      channel.onPostgresChanges(
        event: PostgresChangeEvent.delete,
        schema: 'public',
        table: table,
        filter:
            filters.isNotEmpty ? filters.first : null, // Use the first filter
        callback: (payload) async => await deleteCallback(),
      );
    }

    // Activate the channel
    channel.subscribe();

    final result =
        "Subscribed to table: $table with specified query filters and callbacks";
    return result;
  } catch (e) {
    // Catch and return any errors
    final result = "Error: ${e.toString()}";
    return result;
  }
}