In the example below, I want to combine 2 firestore queries, but I could not get it to work.
final List<Who> pagedData =
await _query.get().then((QuerySnapshot snapshot) async {
if (snapshot.docs.isNotEmpty) {
_lastDocument = snapshot.docs.last;
} else {
_lastDocument = null;
}
return snapshot.docs.map((QueryDocumentSnapshot e) async {
final data = e.data() as Map<String, dynamic>;
Whoes w = Whoes.fromMap(e.data());
User u = await _firestore
.collection("user")
.doc(data['s'])
.get()
.then((DocumentSnapshot documentSnapshot) => User.fromMap(
documentSnapshot.data()));
return Who(w, u);
}).toList();
});
When I put await
in the user part, things get confused and I couldn't edit it.
What I want to output as a result is List<Who>
What am I missing?
It gives me this error:
The return type
'List<Future<Who>>'
isn't a'Future<List<Who>>'
, as required by the closure's context.
CodePudding user response:
I solved the problem, I leave it here for anyone who encounters this
final List<Who> pagedData =
await _query.get().then((QuerySnapshot snapshot) async {
if (snapshot.docs.isNotEmpty) {
_lastDocument = snapshot.docs.last;
} else {
_lastDocument = null;
}
Iterable<Future<Who>> futureWho =
snapshot.docs.map((QueryDocumentSnapshot e) async {
final data = e.data() as Map<String, dynamic>;
Whoes w = Whoes.fromMap(e.data());
User u = await _firestore
.collection("user")
.doc(data['s'])
.get()
.then((DocumentSnapshot documentSnapshot) => User.fromMap(
documentSnapshot.data()));
return Who(w, u);
});
Future<List<Who>> listWho = Future.wait(futureWho);
return listWho;
});