Flutter future builder displaying nothing after finishing - firestore - firebase

Question

I'm trying to display a future builder based on firestore database, but now all I'm getting is a blank screen after finishing the circular progress indicator.
Any help would be greatly appreciated.
Firestore function :
Future<List<Item>> getFavourites() async{
List<Item> _itemList= [];
var firebaseUser=await FirebaseAuth.instance.currentUser();
Firestore.instance.collection("users").document(firebaseUser.uid).get().then((querySnapshot){
List value = querySnapshot.data["favourites"];
if(value.length>0){
value.forEach((element) {
Firestore.instance.collection("items").document(element).get().then((value){
Item item= Item.fromMap(value.data);
_itemList.add(item);
});
});
}
});
return _itemList;
}
FutureBuilder :
FutureBuilder(
future: getFavourites(),
builder:(BuildContext context,AsyncSnapshot<List<Item>> snapshot){
if(snapshot.connectionState!=ConnectionState.waiting){
//print(snapshot.data[0].name);
return
ListView(
children: <Widget>[
SizedBox(height: 10.0),
Text(
"Favorites",
style: TextStyle(
fontSize: 23,
),
),
SizedBox(height: 10.0),
GridView.builder(
shrinkWrap: true,
primary: false,
physics: NeverScrollableScrollPhysics(),
gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
crossAxisCount: 2,
childAspectRatio: MediaQuery.of(context).size.width /
(MediaQuery.of(context).size.height / 1.25),
),
itemCount: snapshot.data == null ? 0 :snapshot.data.length,
itemBuilder: (BuildContext context, int index) {
return GridItem(
img: snapshot.data[index].img,
name: snapshot.data[index].name,
category: snapshot.data[index].category,
id: snapshot.data[index].id,
);
},
),
SizedBox(height: 30),
],
);
}
else{
return Center(
child: CircularProgressIndicator(),
);
}
}
),
'Item' is a class containing all the variables as in the firestore collection.

Answer 1

Use the following method:
Future<List<Item>> getFavourites() async{
List<Item> _itemList= [];
var firebaseUser= await FirebaseAuth.instance.currentUser();
DocumentSnapshot snapshot = await Firestore.instance.collection("users").document(firebaseUser.uid).get();
List value = snapshot.data["favourites"];
if(value.length>0){
value.forEach((element) async{
DocumentSnapshot docSnapshot = await Firestore.instance.collection("items").document(element).get();
Item item= Item.fromMap(docSnapshot.data);
_itemList.add(item);
});
}
return _itemList;
}
In the FutureBuilder use :
if(snapshot.connectionState==ConnectionState.done){

Answer 2

Have you tried to check for:
if(snapshot.connectionState==ConnectionState.done){
instead of
if(snapshot.connectionState!=ConnectionState.waiting){
?