How to order documents by a field content in firestore flutter - firebase

Question

I have a collection of rooms for a hotel. When i add a new one or show the rooms list, they don't show from 1 to 5. Is there a way to order the rooms by their number?
The documents in room collection have their id generated automatically, and every room have a field called room number (ex : 1,2,3 ..)
final rooms = Provider.of<List<Room>>(context) ?? [];
return StreamProvider<List<Room>>.value(
initialData: [],
value: DatabaseService().singleRoom,
child: Scaffold(
appBar: AppBar(
title: Text("Liste des chambre single"),
backgroundColor: Colors.blue,
elevation: 2.0,
leading: IconButton(icon: Icon(Icons.chevron_left),onPressed: ()=> Navigator.pushReplacementNamed(context, '/room_type_screen'),),
actions: [
ElevatedButton.icon(
icon: Icon(Icons.home),
label: Text(""),
onPressed: ()=> Navigator.pushReplacementNamed(context, '/admin_home'),
),
ElevatedButton.icon(
icon: Icon(Icons.add),
label: Text(""),
onPressed: ()=> Navigator.pushNamed(context, '/add_room'),
),
],
),
body: ListView.builder(
itemCount: rooms.length,
itemBuilder: (context,index){
return RoomTile(room : rooms[index]);
},
),
),
Widget build(BuildContext context) {
void deleteRoomFromDatabase(String id){
final CollectionReference singleRoomCollection = FirebaseFirestore.instance.collection("rooms/single/room");
singleRoomCollection.doc(id).delete();
}
return Padding(
padding: EdgeInsets.only(top: 10.0),
child: Card(
margin: EdgeInsets.fromLTRB(20, 6, 20, 0),
child: GridTileBar(
backgroundColor: Color(0xFFBDBDBD),
leading: CircleAvatar(
radius: 30.0,
backgroundColor: Colors.orange,
// backgroundImage: AssetImage('assets/6074.jpg'),
child: Text("${room.numChambre.toString().substring(1)}",
style: TextStyle(
color: Colors.white,
fontSize: 25.0,
fontWeight: FontWeight.bold
),
),
),
title: room.reserver?Text("Chambre réservé"):Text('Chambre disponible',style: TextStyle(fontSize: 20),),
subtitle: Text("Prix : "+room.prix.toString()),
trailing: IconButton(
icon: Icon(Icons.delete),
onPressed: (){
deleteRoomFromDatabase(room.roomId);
},
),
),
),
);
}

Answer 1

if you want to order your result from:
FirebaseFirestore.instance.collection("rooms/single/room")
use the .orderBy() function.
FirebaseFirestore.instance.collection("rooms/single/room").orderBy("FieldInFirestoreToOrderBy", descending: true/false)
If you wanna filter the result you can also use the .where function