Breaking Changes & Deprecations

[gaetanosestito]

Hey all,
Firebase's API for flutter has changed the way developers integrate Flutter applications with Firebase. So exist a migration guide to help with updating existing and new projects for Flash chat.
Please check it out: Migration Guide

About me, I had to do a call to Firebase.initializeApp(); in order to run successuful.

[mohitnakum]

also change before:FirebaseUser loggedInUser; after:User loggedInUser; because FierbaseUser Deprecated
and currentUser now synchronize so not needed async.
Accessing the current user via currentUser() is now synchronous via the currentUser getter.
https://firebase.flutter.dev/docs/migration/

[dryusha]

Yeah..
I change my main() function into main.dart file like dat

---

....
void main() async {
WidgetsFlutterBinding.ensureInitialized();
await Firebase.initializeApp();
runApp(FlashChat());
}
....

---

and second changes its import firebase auth and deprecated FirebaseUser change to auth.User
example for chat screen.

---

import 'package:firebase_auth/firebase_auth.dart' as auth;
...
auth.User loggedInUser;

@OverRide
void initState() {
super.initState();

getCurrentUser();

}

void getCurrentUser() {
try {
final user = _auth.currentUser;
if (user != null) {
loggedInUser = user;
print(loggedInUser.email);
}
} catch (e) {
print(e);
}
}
...

---

Lesson N18-19.
Also Firestore is deprecated need to used FirebaseFirestore,
final _fireStore = FirebaseFirestore.instance;
if u are using streams, snapshot.documents is deprecated too and need to call snapshot.docs with responses data func.

---

void getMessages() async {
await for (var snapshot in _fireStore.collection('messages').snapshots()) {
for (var message in snapshot.docs) {
print(message.data());
}
}
}

---

[digitpk]

Also, guide the latest code regarding stream builder (L#21. Turning Streams into Widgets Using the StreamBuilder) as I didn't get the expected results.

mine code is:
StreamBuilder(
stream: _firestore.collection('messages').snapshots(),
builder: (context, snapshot) {
if (snapshot.hasData) {
final messages = snapshot.data.docs;
List messageWidgets = [];
for (var message in messages) {

// i get the error here on the parenthesis
final messageText = message.data();
final messageSender = message.data();

                final messageWidget =
                    Text('$messageText from $messageSender');
                messageWidgets.add(messageWidget);
              }
            }
          },
        ),

[digitpk]

I got this error fix by using adding this:

// i get the error fix here by adding fields after the parenthesis
final messageText = message.data()['field 1'];
final messageSender = message.data()['field 2'];

[FredWolfe]

@digitpk

this is how I fixed the buildstream error

StreamBuilder(
stream: _fireStore.collection('messages').snapshots(),
builder: (context, snapshot) {
if (snapshot.hasData) {}
final messages = snapshot.data.docs;
List messageWidgets = [];
for (var message in messages) {
final messageText = message.data()['text'];
final messageSender = message.data()['sender'];

              final messageWidget =
                  Text('$messageText from $messageSender');
              messageWidgets.add(messageWidget);
            }
            return Column(
              children: messageWidgets,
            );
          },
        ),

[steph9600]

final messageText = message.data()['text'];
final messageSender = message.data()['sender'];

isn't working for me. i get an error: The operator '[]' isn't defined for the type 'Object'. (undefined_operator at [flash_chat] lib\screens\chat_screen.dart:114)

Wondering if anybody has encountered this/has a fix

[LoneWolfPJT]

final messageText = message['text'];
final messageSender = message['sender'];

you can fix it

[steph9600]

worked like a charm. thanks!

[dyardy]

This was final StreamBuilder returned from _firestore.collection('messages').snapshots(); Hope this helps someone.

StreamBuilder(
    stream: _firestore.collection('messages').snapshots(),
    builder: (BuildContext context,
        AsyncSnapshot<QuerySnapshot> snapshot) {
      if (snapshot.hasData) {
        final messages = snapshot.data?.docs;
        List<Text> messageWidgets = [];
        for (var message in messages!) {
          final messageText = message['text'];
          final messageSender = message['sender'];
          final messageWidget =
              Text('$messageText from $messageSender');

          messageWidgets.add(messageWidget);
        }
        return Column(
          children: messageWidgets,
        );
      }
      return Text('no data');
      // return Text('${snapshot.data}');
    }),

[Yougraj]

This was final StreamBuilder returned from _firestore.collection('messages').snapshots(); Hope this helps someone.

StreamBuilder(
    stream: _firestore.collection('messages').snapshots(),
    builder: (BuildContext context,
        AsyncSnapshot<QuerySnapshot> snapshot) {
      if (snapshot.hasData) {
        final messages = snapshot.data?.docs;
        List<Text> messageWidgets = [];
        for (var message in messages!) {
          final messageText = message['text'];
          final messageSender = message['sender'];
          final messageWidget =
              Text('$messageText from $messageSender');

          messageWidgets.add(messageWidget);
        }
        return Column(
          children: messageWidgets,
        );
      }
      return Text('no data');
      // return Text('${snapshot.data}');
    }),

thank you

[ravi238873]

This was final StreamBuilder returned from _firestore.collection('messages').snapshots(); Hope this helps someone.

StreamBuilder(
    stream: _firestore.collection('messages').snapshots(),
    builder: (BuildContext context,
        AsyncSnapshot<QuerySnapshot> snapshot) {
      if (snapshot.hasData) {
        final messages = snapshot.data?.docs;
        List<Text> messageWidgets = [];
        for (var message in messages!) {
          final messageText = message['text'];
          final messageSender = message['sender'];
          final messageWidget =
              Text('$messageText from $messageSender');

          messageWidgets.add(messageWidget);
        }
        return Column(
          children: messageWidgets,
        );
      }
      return Text('no data');
      // return Text('${snapshot.data}');
    }),

This works and consider this as final solution.

[FredWolfe]

This was final StreamBuilder returned from _firestore.collection('messages').snapshots(); Hope this helps someone.

StreamBuilder(
    stream: _firestore.collection('messages').snapshots(),
    builder: (BuildContext context,
        AsyncSnapshot<QuerySnapshot> snapshot) {
      if (snapshot.hasData) {
        final messages = snapshot.data?.docs;
        List<Text> messageWidgets = [];
        for (var message in messages!) {
          final messageText = message['text'];
          final messageSender = message['sender'];
          final messageWidget =
              Text('$messageText from $messageSender');

          messageWidgets.add(messageWidget);
        }
        return Column(
          children: messageWidgets,
        );
      }
      return Text('no data');
      // return Text('${snapshot.data}');
    }),

thanks so much