如何在 flutter 中使用 streambuilder 从 firestrome 获取用户单个详细信息

Question

我正在尝试使用 Flutter 和 Firestore 构建应用程序。使用 StreamBuilder 加载当前用户单个文件以将其显示在文本中时，出现以下错误

════════ 组件库捕获异常═════════════════════════════════ ═══ 构建 StreamBuilder>(dirty, state: _StreamBuilderBaseState, AsyncSnapshot>>#8a26d): 错误状态：无法获取不存在的 DocumentSnapshotPlatform 上的字段。

这是我的代码

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

class Status extends StatefulWidget {
  Status({Key? key}) : super(key: key);
  @override
  State<Status> createState() => _StatusState();
}

class _StatusState extends State<Status> {
  @override
  Widget build(BuildContext context) {
    return StreamBuilder<DocumentSnapshot>(
        stream: FirebaseFirestore.instance
            .collection("Users")
            .doc(FirebaseAuth.instance.currentUser!.uid)
            .snapshots(),
        builder: (context, AsyncSnapshot snapshot) {
          if (!snapshot.hasData) {
            return Text("Loading");
          } else if (snapshot.hasError) {
            return Text('Something went wrong');
          } else if (snapshot.connectionState == ConnectionState.waiting) {
            return CircularProgressIndicator();
          }
          dynamic data = snapshot.data;
          return new Text(data['status']);
        });
  }
}

Answer 1

你需要通过

DocumentSnapshot to AsyncSnapshot.. Try this code

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

 class Status extends StatefulWidget {
   Status({Key? key}) : super(key: key);
  @override
   State<Status> createState() => _StatusState();
 }

 class _StatusState extends State<Status> {

 final Stream<DocumentSnapshot> _usersStream = FirebaseFirestore.instance
  .collection("Users")
  .doc(FirebaseAuth.instance.currentUser.uid)
  .snapshots()

 @override
 Widget build(BuildContext context) {
  return StreamBuilder<DocumentSnapshot>(
     stream: _usersStream,
      builder: (context,  AsyncSnapshot<DocumentSnapshot> snapshot) {
       if (!snapshot.hasData) {
        return Text("Loading");
      } else if (snapshot.hasError) {
        return Text('Something went wrong');
      } else if (snapshot.connectionState == ConnectionState.waiting) {
        return CircularProgressIndicator();
      }
      dynamic data = snapshot.data;
      return new Text(data['status']);
    });
  }
 }