FutureBuilder can't "see" data / snapshot.hasData - firebase

Question

I have a Future function to get data from Firebase, that is not empty queries correctly:
Future getProducts(vendorId) async {
await vendorsInfoColl.doc(vendorId)
.collection("products")
.get()
.then((QuerySnapshot querySnapShot) async {
if (querySnapShot.docs.isNotEmpty){
print('not empty');
print(querySnapShot.docs);
return querySnapShot.docs;
} else {
print('snapshot empty');
return null;
}
});
}
I just have trouble getting a FutureBuilder see it. Keeps saying there is empty data.
Widget build(BuildContext context) {
return AlertDialog(
// pull title from db
// title: Future Text(vendorTitle.toString()),
title: Text(vendorTitle.toString()),
content: FutureBuilder(
future: VendorDatabase().getProducts(widget.vendorId),
builder: (BuildContext context, AsyncSnapshot snapshot) {
print(snapshot.connectionState);
if (snapshot.connectionState == ConnectionState.waiting) {
return CircularProgressIndicator();
} else if (snapshot.connectionState == ConnectionState.done) {
if (snapshot.hasError) {
return const Text('Error');
} else if (snapshot.hasData) {
var blabla = snapshot.data;
print('there is snapshot data: $blabla');
return ListView.builder(
itemCount: 3,
itemBuilder: (context, index) {
return ListTile(
title: Text(blabla['products']) //<-- i know this is wrong but can't fixt it till future builder actually sees some data.
);
}
);
} else {
return const Text('Empty data');
}
} else {
return Text('State: ${snapshot.connectionState}');
}
}
)
);
}
It would be great if can also get some tips on how to put it in a list :)

Answer 1

You're not returning anything inside getProducts:
Future getProducts(vendorId) async {
return await vendorsInfoColl.doc(vendorId)
.collection("products")
.get()
.then((QuerySnapshot querySnapShot) async {
if (querySnapShot.docs.isNotEmpty){
return querySnapShot.docs;
} else {
return null;
}
});
}
To avoid this in the future, declare a type in your Future:
// vvvvvvvvvvvvvvvv
Future<List<Document>> getProducts(vendorId) async {