StreamBuilder<UserData>(dirty, state: _StreamBuilderBaseState<UserData, AsyncSnapshot<UserData>>#e2c02):
type 'Future<QuerySnapshot>' is not a subtype of type 'Stream<dynamic>' of 'function result' 下面是我的代码 Stream
yield* FirebaseFirestore.instance The type 'Future<QuerySnapshot>' implied by the 'yield' expressionmust be assignable to 'Stream<QuerySnapshot>'
class SearchService {
Stream<QuerySnapshot>