My document contain array of objects as shown in image I'm trying to use transaction to update product_quantity as the user press add or minus button. How to access the usercart and update product_quantity field. The code that I have right now what it does is only to create new field with its value to this document
Future<void> updateCartQty(qty) {
DocumentReference documentReference = FirebaseFirestore.instance
.collection('Users')
.doc(_currentUser!.uid)
.collection("Cart")
.doc(_currentUser!.uid);
return FirebaseFirestore.instance
.runTransaction((transaction) async {
// Get the document
DocumentSnapshot snapshot = await transaction.get(documentReference);
if (!snapshot.exists) {
throw Exception("product does not exist!");
}
transaction.update(documentReference, {'product_quantity': qty});
return qty;
})
.then((value) => print("update cart"))
.catchError((error) => print("Failed to update product cart: $error"));
}
Related
My goal is to handle "likes" on items in my app like so: a given user can toggle his like on a given item.
So I created a collection "Likes" with two properties:
adId as a string
userId as a string
For a userId to like an adId consists in adding a document in the collection.
But because having multiple (adId, userId) document is nonsense, I'd like to handle the unicity of the document.
How to do this efficiently?
What I initially planned to do is write a toggle() function like so:
class Ad {
/// The ad ID
String id;
/// Toggle like and returns the document [id].
void toggle({required String userId}) async {
// Don't let users like their own ads
//if (ad.ownerUid == loggedUser?.uid) return null;
// = Actually store the document
final snapshots = await FirebaseFirestore.instance
.collection(collectionName)
.where("adId", isEqualTo: ad.id)
.where("userId", isEqualTo: userId)
.get();
final docs = snapshots.docs;
if (docs.isEmpty) {
// = Actually store the document
await FirebaseFirestore.instance
.collection(collectionName)
.add({"adId": ad.id, "userId": userId, "on": Timestamp.now()});
} else {
for (final doc in docs) {
await FirebaseFirestore.instance
.collection(collectionName)
.doc(doc.id)
.delete();
}
}
}
}
I want to get field value.
my code is..
void _checkNumner(String number) async {
final userRef = firestore.collection('users');
var documentSnapshot =
await userRef.where("number", isEqualTo: true).get().then((num) {
QuerySnapshot<Map<String, dynamic>> number = num;
print(number);
print("test");
});
print(documentSnapshot);
}
but my console is
how I get field number?
I want to load number values in all docs.
I'm so beginer. T.T
Please reply from the masters
Thank you
Firebase firestore is a NoSQL, document-oriented database. User Data is stored in documents which are organized into collection , i.e collection contains list of document. In simpler words we can say QuerySnapshot contains/provide group of DocumentSnapshot. more about firestore data model
Collection --> QuerySnapshot --> Group of DocumentSnapshot
Document --> DocumentSnapshot
1) Fetch from collection - QuerySnapshot
Here we'll get list of DocumentSnapshots, we can filter by using where commad
Future<void> checkNumber(int number) async {
final QuerySnapshot snapshot = await FirebaseFirestore.instance
.collection('users')
.where("number", isEqualTo: number)
.get();
snapshot.docs.isEmpty
? {
//TODO: your code here
debugPrint("no data found")
}
: {
for (DocumentSnapshot element in snapshot.docs)
{
//TODO: your code here
debugPrint("number is: ${element['number']}"),
debugPrint("name is: ${element['name']}"),
}
};
}
1) Fetch from document - DocumentSnapshot
To fetch data from document we require documentId, and we get a single documentSnapshot instead of multiple like in above way.
Future<void> checkNumberWithDocId() async {
const String docId = 'aaaa';
final DocumentSnapshot snapshot = await FirebaseFirestore.instance.collection('users').doc(docId).get();
snapshot.exists
? {
//TODO: your code here
debugPrint("no data found")
}
: {
//TODO: your code here
debugPrint("number is: ${snapshot['number']}"),
debugPrint("name is: ${snapshot['name']}"),
};
}
Im trying to fetch the documents from a subcollection which is in another document, and when I try to fetch the docs and fill a local list with the "docs data" it doesn't fill it, can anyone tell me what I'm doing wrong here?
My method of when I try to fetch the subcollection:
static Stream<List<CheckInOutModel>> employeeCheckInOutStream() {
return firebaseFirestore
.collection('employees')
.doc(auth.currentUser!.uid)
.collection('employeeList')
.snapshots()
.asyncMap((QuerySnapshot querySnapshot) {
final List<CheckInOutModel> employeesCheckInOutList = [];
for (final element in querySnapshot.docs) {
firebaseFirestore
.collection('employees')
.doc(auth.currentUser!.uid)
.collection('employeeList')
.doc(element.id)
.collection('checkInOutList')
.snapshots()
.asyncMap((QuerySnapshot query) {
for (final element in query.docs) {
final employeeCheckInOutModel =
CheckInOutModel.fromDocumentSnapshot(
documentSnapshot: element,
);
employeesCheckInOutList.add(employeeCheckInOutModel);
}
});
}
return employeesCheckInOutList;
});
}
My method when I fetch the fields of the documents that the subcollection is in:
static Stream<List<EmployeeModel>> employeeStream() {
return firebaseFirestore
.collection('employees')
.doc(auth.currentUser!.uid)
.collection('employeeList')
.snapshots()
.map((QuerySnapshot query) {
final List<EmployeeModel> employees = [];
for (final employee in query.docs) {
final employeeModel =
EmployeeModel.fromDocumentSnapshot(documentSnapshot: employee);
employees.add(employeeModel);
}
return employees;
});
}
So I figured out what I did wrong here, I tried to call a stream of it when I only needed it when a callBack is called, so I changed the logic accordingly and went with Future instead Stream
My updated code:
static Future<List<CheckInOutModel>> employeeCheckInOutStream({
required String id,
}) async {
final List<CheckInOutModel> employeesCheckInOutList = [];
final query = await firebaseFirestore
.collection('employees')
.doc(auth.currentUser!.uid)
.collection('employeeList')
.doc(id)
.collection('checkInOutList')
.get();
for (final employee in query.docs) {
final employeeCheckInOutModel = CheckInOutModel.fromDocumentSnapshot(
documentSnapshot: employee,
);
employeesCheckInOutList.add(employeeCheckInOutModel);
}
return employeesCheckInOutList;
}
I have a favourites collection saved under a users collection. Each of the favourite documents has one field which contains a product_Id. I want to retrieve this product_id value and use it to query another collection. This second collection holds the actual products documents.
Retrieving all the documents in the favourite collection. What do I do next to get the value of the product_id fields as strings?
getIdsfromUserFavs(userId) async {
var _favData = await _usersCollectionReference
.doc(userId)
.collection('favourites')
.get();
}
This is the second method that is used to query the products collection. This method needs the String value from above in order to successfully make the query.
Future<QuerySnapshot<Object?>> queryFavsCollection(value) async {
var _favedProducts = await _productsCollectionReference
.where('prod_id', isEqualTo: value)
.get();
print(value);
return _favedProducts;
}
I am using a futureBuilder in the UI.
THis is one way I have tried(The problem with this is that I don't get any data returned):
getIdsfromUserFavs(userId) async {
var _favData = await _usersCollectionReference
.doc(userId)
.collection('favourites')
.get();
var allData = _favData.docs.map((doc) => doc.data()).toList();
allData.forEach((element) async {
String value = element['prod_id'];
print(value);
await queryFavsCollection(value);
});
}
Future<QuerySnapshot<Object?>> queryFavsCollection(value) async {
var _favedProducts = await _productsCollectionReference
.where('prod_id', isEqualTo: value)
.get();
print(value);
return _favedProducts;
}
I can see that the above methods print the ids to the console. But the FutureBuilder doesn't receive any data:
I/flutter ( 4628): 3nHHEWuCDXvbhYfT8ljY
I/flutter ( 4628): MptYFV1oXhflDYkdQyIP
I/flutter ( 4628): Fd2ntXyNVmjn0D6mG3RA
Below function will return all data from favourite collection
Future<QuerySnapshot<Map<String, dynamic>>> getIdsfromUserFavs(userId) async {
QuerySnapshot<Map<String, dynamic>> _favData = await _usersCollectionReference
.doc(userId)
.collection('favourites')
.get();
return _favData; // This will return all data of favourite collection
}
After that you can return List of desire data as shown in below function
Future<List<QueryDocumentSnapshot<Map<String, dynamic>>>> queryFavsCollection(userId) async {
// Will store data in this list so at the end we can return this
List<QueryDocumentSnapshot<Map<String, dynamic>>> favData = [];
QuerySnapshot<Map<String, dynamic>> _favData =
await getIdsfromUserFavs(userId);
for (QueryDocumentSnapshot<Map<String, dynamic>> data in _favData.docs) {
String value = data['prod_id'];
QuerySnapshot<Map<String, dynamic>> _fav = await
_productsCollectionReference
.where('prod_id', isEqualTo: value)
.get();
if (_fav.docs.isNotEmpty) {
_fav.docs.forEach((element) {
favData.add(element);
});
}
}
return favData;
}
Now you can use FutureBuilder as shown below
FutureBuilder<List<QueryDocumentSnapshot<Map<String, dynamic>>>>(
future: queryFavsCollection(userId),
builder: (context, snapshot) {
if (!snapshot.hasData) {
return Text('Loading...');
}
return Text('you data');
},
);
For better practice kindly refer this. This is from flutter documentation
"The future must have been obtained earlier, e.g. during State.initState, State.didUpdateWidget, or State.didChangeDependencies. It must not be created during the State.build or StatelessWidget.build method call when constructing the FutureBuilder. If the future is created at the same time as the FutureBuilder, then every time the FutureBuilder's parent is rebuilt, the asynchronous task will be restarted."
I have a collection named requests and inside that collection I have many Document. I want to get the Id of each document present inside that collection
Firestore.instance
.collection(FirebaseCollection.user)
.where(UserCollectionField.mobile, isEqualTo: mobile)
.getDocuments()
.then((snapshot) {
var id = snapshot.documents[0].documentID;
}).catchError((error) {
});
also you can make list of user id ex.
Firestore.instance
.collection(FirebaseCollection.user)
.where(UserCollectionField.mobile, isEqualTo: mobile)
.getDocuments()
.then((querySnapshot) async {
var list = querySnapshot.documents;
list.forEach((document) {
adminlist.add(document.documentID);
});
});