如何使用 Flutter 配置 Firebase Firestore 设置

Posted 2023-02-23

【中文标题】如何使用 Flutter 配置 Firebase Firestore 设置

【英文标题】：How to Configure Firebase Firestore settings with Flutter

【发布时间】：2018-12-09 07:28:39

【问题描述】：

我正在评估Firestore Plugin for Flutter。

这个 sn-p 按预期工作，它在按下浮动按钮时将一条记录插入到 firestore：

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

void main() => runApp(new MyApp());

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


class MyHomePage extends StatefulWidget 
  MyHomePage(Key key, this.title) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => new _MyHomePageState();


class _MyHomePageState extends State<MyHomePage> 
  int _counter = 0;

  Firestore firestore;

  _MyHomePageState() 
    firestore = Firestore.instance;
  

  void _addBoard() 
    setState(() 
      _counter++;
      firestore.collection("boards").document().setData( 'name': 'mote_$_counter', 'descr': 'long descr $_counter' );
    );
  

  @override
  Widget build(BuildContext context) 
    return new Scaffold(
      appBar: new AppBar(
        title: new Text(widget.title),
      ),
      body: new Center(
        child: new Column(
         mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            new Text(
              'You have pushed the button this many times:',
            ),
            new Text(
              '$_counter',
              style: Theme.of(context).textTheme.display1,
            ),
          ],
        ),
      ),
      floatingActionButton: new FloatingActionButton(
        onPressed: _addBoard,
        child: new Icon(Icons.add),
      ), 
  

使用flutter run 运行控制台显示警告：

W/Firestore(31567): (0.6.6-dev) [Firestore]: The behavior for java.util.Date objects stored in Firestore is going to change AND YOUR APP MAY BREAK.
W/Firestore(31567): To hide this warning and ensure your app does not break, you need to add the following code to your app before calling any other Cloud Firestore methods:
W/Firestore(31567): 
W/Firestore(31567): FirebaseFirestore firestore = FirebaseFirestore.getInstance();
W/Firestore(31567): FirebaseFirestoreSettings settings = new FirebaseFirestoreSettings.Builder()
W/Firestore(31567):     .setTimestampsInSnapshotsEnabled(true)
W/Firestore(31567):     .build();
W/Firestore(31567): firestore.setFirestoreSettings(settings);
W/Firestore(31567): 
W/Firestore(31567): With this change, timestamps stored in Cloud Firestore will be read back as com.google.firebase.Timestamp objects instead of as system java.util.Date objects. So you will also need to update code expecting a java.util.Date to instead expect a Timest        

有一种方法可以配置 FirebaseFirestore 实例，从而通过日期设置解决此问题？

【问题讨论】：

我面临同样的问题，GitHub 中有一个问题已打开但从未关闭，所以我不喜欢这样的声音，但我一直在等待这个问题的任何进展@ 987654322@

@attdona - 你能展示一下你是如何使用await firestore.settings(timestampsInSnapshotsEnabled: true); 来修改现有代码的吗？我很怀疑如何使用它。

【参考方案1】：

从cloud_firestore 0.8.2解决问题，先将pubspec.yaml中的依赖升级为：

dependencies:
  cloud_firestore: ^0.8.2+1

Firestore::setting 返回一个 Future，因此必须在异步函数中调用它。

这足以使示例代码工作：

void main() async 
  final Firestore firestore = Firestore();
  await firestore.settings(timestampsInSnapshotsEnabled: true);

  runApp(new MyApp());

然后，在实际添加文档时，显式添加一个 createdAt（或任何你想称呼它的名称）字段，如下所示：

    Firestore.instance
        .collection('customer')
        .add(
      "name": customerNameController.text,
      "createdAt": FieldValue.serverTimestamp()
    ).then((res)  ...

【参考方案2】：

应该在 0.8.2 版本中解决。

请参阅example 了解如何使用设置。

【讨论】：

在这里 - github.com/flutter/plugins/tree/master/packages/cloud_firestore 在使用部分没有提到 await firestore.settings(timestampsInSnapshotsEnabled: true); 的事情。所以，我对使用什么感到有点困惑。

链接已关闭。请将解决方案放在这里，而不是提供其他页面的链接。