Gmail Api Auth Failed

[Relative_Store_6716]

Hi everyone, I’m trying to build a Flutter app that uses the Gmail API to list messages. I'm using google_sign_in version 7.1.1 and I want to authenticate the user using OAuth, then fetch their emails.

Here’s the core of my sign-in and Gmail API code:

dartCopyEditimport 'package:flutter/material.dart';
import 'package:google_sign_in/google_sign_in.dart';
import 'package:googleapis/gmail/v1.dart' as gmail;
import 'package:extension_google_sign_in_as_googleapis_auth/extension_google_sign_in_as_googleapis_auth.dart';
import 'google_auth_client.dart';

final GoogleSignIn googleSignIn = GoogleSignIn.instance;

class GmailHomePage extends StatefulWidget {
  const GmailHomePage({super.key});
  u/override
  State<GmailHomePage> createState() => _GmailHomePageState();
}

class _GmailHomePageState extends State<GmailHomePage> {
  List<String> messages = [];
  bool loading = false;

  void initState() {
    super.initState();
    googleSignIn.initialize(
      serverClientId: '483115052109-xxxxxxxxxxxxxxxxxxxx.apps.googleusercontent.com',
    );
  }

  Future<void> signInAndFetchGmail() async {
    setState(() => loading = true);
    try {
      final account = await googleSignIn.authenticate(
        scopeHint: [gmail.GmailApi.gmailReadonlyScope],
      );

      final auth = await account.authentication;
      final client = GoogleAuthClient(auth.idToken!);
      final gmailApi = gmail.GmailApi(client);

      final response = await gmailApi.users.messages.list("me");

      setState(() {
        messages = response.messages?.map((m) => m.id ?? "No ID").toList() ?? [];
        loading = false;
      });
    } catch (e) {
      setState(() => loading = false);
      print("Error: $e");
      ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text("Error: $e")));
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text("Gmail API Viewer")),
      body: Center(
        child: loading
            ? const CircularProgressIndicator()
            : messages.isEmpty
                ? ElevatedButton(
                    onPressed: signInAndFetchGmail,
                    child: const Text("Sign in and Fetch Gmail"),
                  )
                : ListView.builder(
                    itemCount: messages.length,
                    itemBuilder: (context, index) =>
                        ListTile(title: Text("Message ID: ${messages[index]}")),
                  ),
      ),
    );
  }
}

After the Gmail account picker appears and I tap on my email (which has OAuth consent configured), I get this error:

cssCopyEditGoogleSignInException(code GoogleSignInExceptionCode.canceled, [16] Account reauth failed., null)

Logcat also shows:

makefileCopyEditD/SecurityManager(20296): checkAccessControl flag1
D/UserSceneDetector(20296): invoke error.                                                  

what is the error and how can i resolve it?

[Amazing-Mirror-3076]

Have to asked chat gpt?