Flutter cloud_firestore在Android上的插件事务

Question

是否有人使用cloud_firestore插件成功地运行了事务？我得到以下错误：

E/AndroidRuntime(26208):致命异常:AsyncTask#2 E/AndroidRuntime(26208):process:io.flutter.plugins.googleSigninexample，PID:26208 E/AndroidRuntime(26208):java.lang.runtimeException:>执行doInBackground()E/AndroidRuntime(26208):at Android.os.AsyncTask$3时出错。Done(AsyncTask.java:353)E/AndroidRuntime(26208):at java.util.concurrent.futureTask.setException(FutureTask.java:252)E/AndroidRuntime(26208):at java.util.concurrent.futureTask.run(FutureTask.java:271)E/AndroidRuntime(26208):at android.os.AsyncTask$serialExecutor$1.run(AsyncTask.java:245)E/AndroidRuntime(26208):at android.os.AsyncTask:245):at tor$worker.run（threadpoolexecutor.java：636）e/AndroidRuntime（26208）：at java.lang.thread.run（thread.java：764）e/AndroidRuntime（26208）：cased by：java.lang.IllegalArgumentException:>提供的文档引用来自不同的Firestore实例。E/AndroidRuntime(26208):at com.google.firebase.firestore.firebaseFirestore.zza（未知来源：17）E/AndroidRuntime(26208):at com.google.firebase.firestore.transaction.get（未知来源：2）E/AndroidRuntime(26208):at io.flutter.plugins.firebase.cloudFirestore.cloudFirestore.cloudFirestore.cloudFirestore.4.doinbackgin(26208):at.java:316)e/androidRuntime(26208):at android.os.asyncTask$2.调用(asynctask.java:333)e/androidRuntime(26208):at java.util.concurrent.futureTask.run(FutureTask.java:266)e/androidRuntime(26208):...4更多d/FlutterNativeView(26208):handlePlatformMessage回复一个分离的视图，channel=plugins.flutter.io/cloud_FireStoreI/FirebaseAuth(26208):[FirebaseAuth:]准备创建到gms实现的服务连接

以下是基于https://github.com/flutter/plugins/tree/master/packages/cloud_firestore#用法的代码：

   final DocumentReference postRef =
    Firestore.instance.document('posts/post1');
    Firestore.instance.runTransaction((Transaction tx) async {
      DocumentSnapshot postSnapshot = await tx.get(postRef);
      if (postSnapshot.exists) {
      await tx.update(postRef,
          <String, dynamic>{'likesCt': postSnapshot.data['likesCt'] + 1});
      }
    });

pubspec.lock：

  cloud_firestore:
    dependency: "direct main"
    description:
      name: cloud_firestore
      url: "https://pub.dartlang.org"
    source: hosted
    version: "0.7.0+2"

颤医生：

Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel beta, v0.3.1, on Microsoft Windows [Version 
10.0.16299.431], locale en-US)
[√] Android toolchain - develop for Android devices (Android SDK 27.0.3)
[√] Android Studio (version 3.1)
X Flutter plugin not installed; this adds Flutter specific functionality.
X Dart plugin not installed; this adds Dart specific functionality.
[√] IntelliJ IDEA Community Edition (version 2018.1)
[√] Connected devices (1 available)

• No issues found!

Answer 1

我用inmain.dart启动了我的应用程序：

final FirebaseApp app =
      await FirebaseApp.configure(options: _options(), name: 'testauth');
final Firestore firestore = Firestore(app: app);
  await firestore.settings(timestampsInSnapshotsEnabled: true);

身份验证之后，我直接转到HomesCreen.Dart，它正在使用新的FireStore.Instance...与Main的完全无关。

由：java.lang.IllegalArgumentException引起：提供的文档引用来自不同的Firestore实例。

所以我把线去掉了

final Firestore firestore = Firestore(app: app);
await firestore.settings(timestampsInSnapshotsEnabled: true);

并最终使事务按预期运行。我认为这个想法是不要同时发生多个实例。