Flutter集成Firebase服务插件firebase_for_all的使用

发布于 1周前 作者 nodeper 来自 Flutter

Flutter集成Firebase服务插件firebase_for_all的使用

摘要

firebase_for_all 插件允许你在所有平台上使用 Firebase 功能而无需更改代码。它利用了以下包:

  • firebase_dart
  • firedart
  • firebase_auth_desktop
  • firebase_core_desktop

在非 Windows 平台上,推荐使用原生库以减少错误和问题的风险。

特性

目前支持以下 Firebase 服务:

  • 认证
  • 云 Firestore
  • 云存储

示例

所有示例位于 example/lib/functions.dart

使用

首先,在你的 pubspec.yaml 文件中添加依赖项:

dependencies:
  firebase_for_all: ^latest

如果通过 FlutterFire CLI 设置 Firebase,初始化应用时会抛出错误。为避免此错误,你可以覆盖依赖项:

dependency_overrides:
  firebase_core_platform_interface: 4.5.1

然后运行 flutter packages get

入门

初始化 Firebase

有两种配置 Firebase 的方法:

旧方法:手动配置

await FirebaseCoreForAll.initializeApp(
    options: FirebaseOptions(
      apiKey: 'XXXXXXXXXXXXXXXXXXXXXX',
      appId: 'XXXXXXXXXXXXXXXXXXXXXX',
      messagingSenderId: 'XXXXXXXXXXX',
      projectId: 'XXXXXXXXXXXXXX',
      authDomain: 'XXXXXXXXXXXXX.firebaseapp.com',
      storageBucket: 'XXXXXXXXXXXXX.appspot.com',
    ),
    firestore: true,
    auth: true,
    storage: true);

新方法:使用 Firebase CLI

await FirebaseCoreForAll.initializeApp(
    options: DefaultFirebaseOptions.currentPlatform,
    firestore: true,
    auth: true,
    storage: true);

云存储

获取 FirebaseAuth 实例:

await FirebaseAuthForAll.instance.createUserWithEmailAndPassword(email: "test@hotmail.com", password: "password123");

云 Firestore

文档与查询快照

QuerySnapshot

FirestoreForAll.instance
    .collection('users')
    .get()
    .then((QuerySnapshotForAll querySnapshot) {
        querySnapshot.docs.forEach((doc) {
            print(doc["first_name"]);
        });
});

DocumentSnapshot

FirestoreForAll.instance
    .collection('users')
    .doc(userId)
    .get()
    .then((DocumentSnapshotForAll documentSnapshot) {
      if (documentSnapshot.exists) {
        print('Document data: ${documentSnapshot.data()}');
      } else {
        print('Document does not exist on the database');
      }
    });

查询

过滤

警告:isNotEqualTowhereNotIn 在桌面端(除了 MacOS)不工作。

FirestoreForAll.instance
    .collection('users')
    .where('age', isGreaterThan: 10)
    .get()
    .then(...);

排序

FirestoreForAll.instance
    .collection('users')
    .orderBy('age', descending: true)
    .get()
    .then(...);

限制

警告:limitToLast 在桌面端(除了 MacOS)不工作。

FirestoreForAll.instance
    .collection('users')
    .limit(2)
    .get()
    .then(...);

起始和结束游标

警告:此功能在桌面端(除了 MacOS)不工作。

FirestoreForAll.instance
    .collection('users')
    .orderBy('age')
    .orderBy('company')
    .startAt([4, 'Alphabet Inc.'])
    .endAt([21, 'Google LLC'])
    .get()
    .then(...);

添加、更新和删除文档

ColRef users = FirestoreForAll.instance.collection('users');

users
    .add({
      'full_name': fullName, // John Doe
      'company': company, // Stokes and Sons
      'age': age // 42
    })
    .then((value) => print("User Added"))
    .catchError((error) => print("Failed to add user: $error"));

users
    .doc("12345")
    .set({
      'full_name': fullName, // John Doe
      'company': company, // Stokes and Sons
      'age': age // 42
    })
    .then((value) => print("User Added"))
    .catchError((error) => print("Failed to add user: $error"));

users
    .doc('ABC123')
    .update({'company': 'Stokes and Sons'})
    .then((value) => print("User Updated"))
    .catchError((error) => print("Failed to update user: $error"));

users
    .doc('ABC123')
    .delete()
    .then((value) => print("User Deleted"))
    .catchError((error) => print("Failed to delete user: $error"));

实时变化

监听集合

CollectionSnapshots collectionSnapshots = FirestoreForAll.instance.collection('users').snapshots();
collectionSnapshots.listen(
  (snapshot) {},
  onDone: () {},
  onError: (e, stackTrace) {},
);

警告:StreamBuilder 对此不起作用。使用以下代码:

CollectionBuilder(
        stream: FirestoreForAll.instance.collection("users").snapshots(),
        builder: (BuildContext context,
            AsyncSnapshot<QuerySnapshotForAll> snapshot) {
          if (snapshot.hasError) {
            return Text('Something went wrong');
          }

          if (snapshot.connectionState == ConnectionState.waiting) {
            return Text("Loading");
          }

          return ListView(
            children:
                snapshot.data!.docs.map((DocumentSnapshotForAll document) {
              Map<String, dynamic> data =
                  document.data() as Map<String, dynamic>;
              return ListTile(
                title: Text(data['name']),
                subtitle: Text(data['surname']),
              );
            }).toList(),
          );
        },
      )

监听文档

DocumentSnapshots documentSnapshots=FirestoreForAll.instance.collection('users').doc('ABC123').snapshots();
documentSnapshots.listen(
  (snapshot) {},
  onDone: () {},
  onError: (e, stackTrace) {},
);

警告:StreamBuilder 对此不起作用。使用以下代码:

DocumentBuilder(
        stream: FirestoreForAll.instance
            .collection("users")
            .doc('ABC123')
            .snapshots(),
        builder: (BuildContext context,
            AsyncSnapshot<DocumentSnapshotForAll> snapshot) {
          if (snapshot.hasError) {
            return Text('Something went wrong');
          }

          if (snapshot.connectionState == ConnectionState.waiting) {
            return Text("Loading");
          }

          return ListTile(
            title: Text(snapshot.data!['name']),
            subtitle: Text(snapshot.data!['surname']),
          );
        },
      )

类型化 CollectionReferenceDocumentReference

final moviesRef = FirestoreForAll.instance.collection('movies').withConverter<User>(
      fromFirestore: (snapshot, _) => User.fromJson(snapshot.map!),
      toFirestore: (movie, _) => movie.toJson(),
    );
// 获取年龄为31岁的用户列表
List<DocumentSnapshotForAll<User>> users = await userRef
    .where('age', isEqualTo: 31)
    .get()
    .then((snapshot) => snapshot.docs);

// 添加一个用户
await userRef.add(
  User(
    name: 'Chris',
    surname: 'Doe',
    age: 20
  ),
);

// 获取ID为42的用户
User user = await userRef.doc('42').get().then((snapshot) => snapshot.data()!);

云存储

上传文件

从文件上传

final storageRef = FirebaseStorageForAll.instance.ref();
final mountainsRef = storageRef.child("mountains.jpg");
Directory appDocDir = await getApplicationDocumentsDirectory();
String filePath = '${appDocDir.absolute}/file-to-upload.png';
File file = File(filePath);

UploadTaskForAll task = mountainsRef.putFile(file);

从字符串上传

String dataUrl = 'data:text/plain;base64,SGVsbG8sIFdvcmxkIQ==';
UploadTaskForAll task = mountainsRef.putString(dataUrl, format: PutStringFormat.dataUrl);

上传原始数据

UploadTaskForAll task = mountainsRef.putData(file.readAsBytesSync());

获取下载链接

await mountainsRef.getDownloadURL();

管理上传

File file = File(filePath);
mountainsRef.putFile(file).snapshotEvents.listen((taskSnapshot) {
  switch (taskSnapshot.state) {
    case TaskState.running:
      // ...
      break;
    case TaskState.paused:
      // ...
      break;
    case TaskState.success:
      // ...
      break;
    case TaskState.canceled:
      // ...
      break;
    case TaskState.error:
      // ...
      break;
  }
});

下载文件

内存中下载

final storageRef = FirebaseStorageForAll.instance.ref();
final islandRef = storageRef.child("images/island.jpg");
const oneMegabyte = 1024 * 1024;
final Uint8List? data = await islandRef.getData(oneMegabyte);

下载到本地文件

final islandRef = storageRef.child("images/island.jpg");

final appDocDir = await getApplicationDocumentsDirectory();
final filePath = "${appDocDir.absolute}/images/island.jpg";
final file = File(filePath);

DownloadTaskForAll downloadTask = await islandRef.writeToFile(file);

管理下载

downloadTask.snapshotEvents.listen((taskSnapshot) {
  switch (taskSnapshot.state) {
    case TaskState.running:
      // TODO: Handle this case.
      break;
    case TaskState.paused:
      // TODO: Handle this case.
      break;
    case TaskState.success:
      // TODO: Handle this case.
      break;
    case TaskState.canceled:
      // TODO: Handle this case.
      break;
    case TaskState.error:
      // TODO: Handle this case.
      break;
  }
});

删除文件

final desertRef = storageRef.child("images/desert.jpg");
await desertRef.delete();

列出所有文件

final storageRef = FirebaseStorage.instance.ref().child("files/uid");
final listResult = await storageRef.listAll();
for (var prefix in listResult.prefixes) {
  // The prefixes under storageRef.
  // You can call listAll() recursively on them.
}
for (var item in listResult.items) {
  // The items under storageRef.
}

新功能

StorageFile

class StorageFile{
  String cloudPath;
  String fileName;
  StorageRef reference;
  String type, extension;
  List<String> relatedDirs;
  int size;
}

StorageDirectory

class StorageDirectory{
  String cloudPath;
  String dirName;
  StorageRef reference;
  List<String> relatedDirs;
}

新函数 - getFiles()

List<StorageFile> files = await storageRef.getFiles();

新函数 - getSize()

final desertRef = FirebaseStorageForAll.instance.ref().child("images/desert.jpg");

int size = await desertRef.getSize();

新函数 - getDirectories()

List<StorageDirectory> files = await storageRef.getDirectories();

新函数 - getDirSize()

final storageRef = FirebaseStorageForAll.instance.ref().child("files/uid");

int size = await storageRef.getDirSize();

完整示例

以下是完整的示例代码:

import 'package:flutter/material.dart';
// ignore: depend_on_referenced_packages
import 'package:firebase_for_all/firebase_for_all.dart';
import 'firebase_options.dart';
import 'functions.dart';

void main() async {
  await FirebaseCoreForAll.initializeApp(
      options: DefaultFirebaseOptions.currentPlatform,
      firestore: true,
      auth: true,
      storage: true);
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(title: "title"),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key, required this.title}) : super(key: key);
  final String title;

  [@override](/user/override)
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  [@override](/user/override)
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: CollectionBuilder(
        stream: FirestoreForAll.instance.collection("users").snapshots(),
        builder: (BuildContext context,
            AsyncSnapshot<QuerySnapshotForAll> snapshot) {
          if (snapshot.hasError) {
            return const Text('Something went wrong');
          }

          if (snapshot.connectionState == ConnectionState.waiting) {
            return const Text("Loading");
          }

          return ListView(
            children:
                snapshot.data!.docs.map((DocumentSnapshotForAll document) {
              Map<String, dynamic> data =
                  document.data() as Map<String, dynamic>;
              return ListTile(
                title: Text(data['name']),
                subtitle: Text(data['surname']),
              );
            }).toList(),
          );
        },
      ),
      floatingActionButton: const FloatingActionButton(
        onPressed: getCollection,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ),
    );
  }
}

更多关于Flutter集成Firebase服务插件firebase_for_all的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html

1 回复

更多关于Flutter集成Firebase服务插件firebase_for_all的使用的实战系列教程也可以访问 https://www.itying.com/category-92-b0.html


在Flutter项目中集成Firebase服务插件,尤其是像firebase_for_all这样可能涵盖多种Firebase服务的插件(尽管需要注意的是,firebase_for_all并不是Firebase官方提供的一个标准插件,这里假设它是一个综合多个Firebase服务的第三方插件),通常涉及以下几个步骤:添加依赖、配置Firebase项目、初始化Firebase服务以及使用相关服务。

由于firebase_for_all不是官方插件,我将基于Flutter官方推荐的Firebase插件集合(如firebase_corefirebase_authfirebase_firestore等)来展示如何集成和使用Firebase服务。这些步骤和代码示例应该非常接近使用firebase_for_all(如果存在的话)的过程。

1. 添加依赖

首先,在你的pubspec.yaml文件中添加所需的Firebase插件依赖。例如,如果你想要集成Firebase身份验证和Firestore数据库,你可以添加如下依赖:

dependencies:
  flutter:
    sdk: flutter
  firebase_core: ^1.13.0 # 核心库,用于初始化Firebase应用
  firebase_auth: ^3.3.10 # 身份验证服务
  cloud_firestore: ^3.1.5 # Firestore数据库服务

然后运行flutter pub get来安装这些依赖。

2. 配置Firebase项目

在Firebase控制台创建一个新的项目,并按照指示配置你的Android和iOS应用。下载google-services.json(对于Android)和GoogleService-Info.plist(对于iOS),并将它们分别放置在android/app/ios/Runner/目录下。

3. 初始化Firebase应用

在你的main.dart文件中,初始化Firebase应用:

import 'package:flutter/material.dart';
import 'package:firebase_core/firebase_core.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp(); // 初始化Firebase应用
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Firebase Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(),
    );
  }
}

4. 使用Firebase服务

身份验证示例

import 'package:firebase_auth/firebase_auth.dart';

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  final FirebaseAuth _auth = FirebaseAuth.instance;

  Future<void> _signInAnonymously() async {
    try {
      UserCredential result = await _auth.signInAnonymously();
      User? user = result.user;
      // 更新UI或执行其他操作
    } catch (e) {
      print(e.toString());
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Firebase Auth Demo'),
      ),
      body: Center(
        child: ElevatedButton(
          onPressed: _signInAnonymously,
          child: Text('Sign in Anonymously'),
        ),
      ),
    );
  }
}

Firestore数据库示例

import 'package:cloud_firestore/cloud_firestore.dart';

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  final FirebaseFirestore _firestore = FirebaseFirestore.instance;

  Future<void> _addData() async {
    try {
      await _firestore.collection('users').add({
        'name': 'John Doe',
        'age': 30,
      });
      // 更新UI或执行其他操作
    } catch (e) {
      print(e.toString());
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Firestore Demo'),
      ),
      body: Center(
        child: ElevatedButton(
          onPressed: _addData,
          child: Text('Add Data to Firestore'),
        ),
      ),
    );
  }
}

以上代码展示了如何在Flutter应用中集成并使用Firebase的核心功能。如果你使用的firebase_for_all插件提供了类似的功能,集成和使用方式应该非常相似,只需参考该插件的文档进行具体实现即可。如果firebase_for_all确实存在且有特殊用法,请参考其官方文档或GitHub仓库中的示例代码。

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