Flutter身份验证插件firebase_auth的使用

Firebase Auth for Flutter

Flutter 的一个插件，用于使用 Firebase Authentication API。

要了解更多关于 Firebase Auth 的信息，请访问 Firebase 网站。

Getting Started

要开始使用 Flutter 的 Firebase Auth，请参阅文档。

Usage

要使用此插件，请访问 身份验证用法文档。

Issues and feedback

请在我们的 issue tracker 中提交特定于 FlutterFire 的问题、错误或功能请求。

非特定于 FlutterFire 的插件问题可以在 Flutter issue tracker 中提交。

要为此插件贡献更改，请查阅我们的 contribution guide，并打开一个pull request。

示例代码

以下是一个完整的示例 demo，演示了如何使用 firebase_auth 插件进行用户身份验证：

// Copyright 2022, the Chromium project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'dart:io';

import 'package:firebase_auth/firebase_auth.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:google_sign_in_dartio/google_sign_in_dartio.dart';

import 'auth.dart';
import 'firebase_options.dart';
import 'profile.dart';

/// Requires that a Firebase local emulator is running locally.
/// See https://firebase.google.com/docs/auth/flutter/start#optional_prototype_and_test_with_firebase_local_emulator_suite
bool shouldUseFirebaseEmulator = false;

late final FirebaseApp app;
late final FirebaseAuth auth;

// Requires that the Firebase Auth emulator is running locally
// e.g via `melos run firebase:emulator`.
Future<void> main() async {
  WidgetsFlutterBinding.ensureInitialized();
  // We're using the manual installation on non-web platforms since Google sign in plugin doesn't yet support Dart initialization.
  // See related issue: https://github.com/flutter/flutter/issues/96391

  // We store the app and auth to make testing with a named instance easier.
  app = await Firebase.initializeApp(
    options: DefaultFirebaseOptions.currentPlatform,
  );
  auth = FirebaseAuth.instanceFor(app: app);

  if (shouldUseFirebaseEmulator) {
    await auth.useAuthEmulator('localhost', 9099);
  }

  if (!kIsWeb && Platform.isWindows) {
    await GoogleSignInDart.register(
      clientId:
          '406099696497-g5o9l0blii9970bgmfcfv14pioj90djd.apps.googleusercontent.com',
    );
  }

  runApp(const AuthExampleApp());
}

/// The entry point of the application.
///
/// Returns a [MaterialApp].
class AuthExampleApp extends StatelessWidget {
  const AuthExampleApp({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Firebase Example App',
      theme: ThemeData(primarySwatch: Colors.amber),
      home: Scaffold(
        body: LayoutBuilder(
          builder: (context, constraints) {
            return Row(
              children: [
                Visibility(
                  visible: constraints.maxWidth >= 1200,
                  child: Expanded(
                    child: Container(
                      height: double.infinity,
                      color: Theme.of(context).colorScheme.primary,
                      child: Center(
                        child: Column(
                          mainAxisAlignment: MainAxisAlignment.center,
                          children: [
                            Text(
                              'Firebase Auth Desktop',
                              style: Theme.of(context).textTheme.headlineMedium,
                            ),
                          ],
                        ),
                      ),
                    ),
                  ),
                ),
                SizedBox(
                  width: constraints.maxWidth >= 1200
                      ? constraints.maxWidth / 2
                      : constraints.maxWidth,
                  child: StreamBuilder<User?>(
                    stream: auth.authStateChanges(),
                    builder: (context, snapshot) {
                      if (snapshot.hasData) {
                        return const ProfilePage();
                      }
                      return const AuthGate();
                    },
                  ),
                ),
              ],
            );
          },
        ),
      ),
    );
  }
}

这个示例展示了如何初始化 Firebase 应用，并根据用户的登录状态切换显示不同的页面。它还展示了如何配置和使用 Firebase 认证模拟器（如果需要）。