How can I get a subcollection on Firebase without specifying it? - firebase

Question

Hey Guys I have these subcollections on my Firebase database under the "vocabulary" collection, but I would need to call them without specifying it, as they are more than one and they are called from the same page. Instead of the collection "colors", is it possible to not specify it as the "documentID" but for the collection?
class CategoryScreen extends StatelessWidget {
final DocumentSnapshot vocabulary;
CategoryScreen(this.vocabulary);
#override
Widget build(BuildContext context) {
return Scaffold(
body: FutureBuilder<QuerySnapshot>(
future: Firestore.instance.collection('vocabulary').document(vocabulary.documentID)
.collection('colors').getDocuments(),
builder: (context, snapshot){
if(!snapshot.hasData)
return Center(
child: CircularProgressIndicator(),);
else
return Column(
children: <Widget>[
Padding(
padding: const EdgeInsets.all(10.0),
child: Card(
elevation: 7.0,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(50)
),
child: Column(
children: <Widget>[
Container(
height: 350.0,
width: 350.0,
decoration: BoxDecoration(
image: DecorationImage(
image: NetworkImage(vocabulary.data["image"]
),
fit: BoxFit.fill),
borderRadius: BorderRadius.only(
topLeft: Radius.circular(50),
topRight: Radius.circular(50)))
),
Container(
height: 70.0,
width: 300.0,
child: Padding(
padding: const EdgeInsets.all(2.0),
child: Center(
child: AutoSizeText(vocabulary.data["name"],
style: TextStyle(
fontFamily: 'Twiddlestix',
fontSize: 25,
fontWeight: FontWeight.bold),
textAlign: TextAlign.center,
minFontSize: 15,
),
)
),
),
],
),
),
),
],
);
},
),
);
}
}

Answer 1

There are no wildcards in Cloud Firestore references to documents. So in order to create a query, you need to know all collection names. If you need to get only some documents within a collection based on a specific property, you'll have to do a query using some field value as a filter.
Instead of the collection "colors", is it possible to not specify it as the "documentID" but for the collection?
No, it's not possible. You cannot substitute that.