Instance of '_JsonQueryDocumentSnapshot'-CodePudding

main screen code :

import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:day_event_viewer/services/firestore.dart';
import 'package:flutter/material.dart';

class TodayEventScreen extends StatefulWidget {
  @override
  _TodayEventScreenState createState() => _TodayEventScreenState();
}

class _TodayEventScreenState extends State<TodayEventScreen> {
  @override
  Widget build(BuildContext context) {
    return SafeArea(
      child: StreamBuilder(
          stream: getUserDatas(),
          builder:
              (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
            if (!snapshot.hasData) {
              return const Text('loading data');
            } else if (snapshot.hasData) {
              return ListView.builder(
                itemCount: snapshot.data!.docs.length,
                itemBuilder: (BuildContext context, int index) {
                  return Text(snapshot.data!.docs[index].toString());
                },
              );
            }
            return const Text('somethng\'s wrong');
          }),
    );
  }
}

stream getUserDatas() code :

import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:day_event_viewer/screens/add_screen.dart';

Stream<QuerySnapshot> getUserDatas() async* {
  final uid = await getUid();
  yield* FirebaseFirestore.instance
      .collection('usersdatas')
      .doc(uid)
      .collection('profile')
      .snapshots();
}

it is giving me "Instance of '_JsonQueryDocumentSnapshot'" in my screen. what is this and how can I get the data in firestore. I'm new to firebase so anyone's help would be appreciated.

CodePudding user response：

you are trying to display instance not the actual value you want,you should try to display return Text(snapshot.data!.docs[index].here the data you want to display.toString());

CodePudding user response：

When you load data from Firestore, you get a DocumentSnapshot for each document. Since you're calling toString() on that here, you see the debug representation of the object in your UI:

itemBuilder: (BuildContext context, int index) {
  return Text(snapshot.data!.docs[index].toString());
},

What you probably want is to get one or more of the fields from the document's data, and display that. Say that your document contains a field called message, you can display that value with:

itemBuilder: (BuildContext context, int index) {
  var doc = snapshot.data!.docs[index];
  var data = doc.data() as Map;
  return Text(data['message']);
},

I recommend also having a look at the documentation on showing realtime results from Firestore in Flutter as it has a quite elaborate example.