get all documents in collection firestore flutter
final _fireStore = FirebaseFirestore.instance;
Future<void> getData() async {
// Get docs from collection reference
QuerySnapshot querySnapshot = await _fireStore.collection('collectionName').get();;
// Get data from docs and convert map to List
final allData = querySnapshot.docs.map((doc) => doc.data()).toList();
//for a specific field
final allData =
querySnapshot.docs.map((doc) => doc.get('fieldName')).toList();
print(allData);
}