Firestore has recently add the new new method FieldValue.arrayUnion(value) and FieldValue.arrayRemove(value) but i couldn't find the implementation in flutter cloud_firestore package. Is there any way to achieve this result ?
Firestore addUpdate: https://firebase.google.com/docs/firestore/manage-data/add-data#update_elements_in_an_array
Here is the simple example to show how to update the array values. My document have an up voters array to add the user id's who have up-votes the document.
configure firestore, the config details can be copied form your google-services.json file
final FirebaseApp app = await FirebaseApp.configure(
name: 'test',
options: const FirebaseOptions(
projectID: 'projid',
googleAppID: 'appid',
apiKey: 'api',
databaseURL: 'your url',
),
);
final Firestore firestore = Firestore(app: app);
await firestore.settings(timestampsInSnapshotsEnabled: true);
update code using transaction
fireStore.runTransaction((Transaction tx) async {
DocumentSnapshot snapshot =
await tx.get(widget._document.reference);
var doc = snapshot.data;
if (doc['upvoters'].contains('12345')) {
await tx.update(snapshot.reference, <String, dynamic>{
'upvoters': FieldValue.arrayRemove(['12345'])
});
} else {
await tx.update(snapshot.reference, <String, dynamic>{
'upvoters': FieldValue.arrayUnion(['12345'])
});
}
});
Hope it helps
Update: And now it seems that it is supported! With the version 0.8.0.
https://pub.dartlang.org/packages/cloud_firestore
And then use FieldValue.arrayUnion and FieldVale.arrayRemove.
There doesn't seems to be a way currently. Please follow the following two github issues:
https://github.com/flutter/flutter/issues/21148 https://github.com/flutter/flutter/issues/20688
