从Firebase读取数据- Flutter

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

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: Text('Firebase Data Reader')),
        body: FirebaseDataReader(),
      ),
    );
  }
}

class FirebaseDataReader extends StatefulWidget {
  @override
  _FirebaseDataReaderState createState() => _FirebaseDataReaderState();
}

class _FirebaseDataReaderState extends State<FirebaseDataReader> {
  final DatabaseReference _databaseReference = FirebaseDatabase.instance.reference();
  List<Map<String, dynamic>> _data = [];

  @override
  void initState() {
    super.initState();
    _databaseReference.child('items').onValue.listen((event) {
      setState(() {
        _data = List.from(event.snapshot.value.values)
            .map((e) => e as Map<String, dynamic>)
            .toList();
      });
    });
  }

  @override
  Widget build(BuildContext context) {
    return ListView.builder(
      itemCount: _data.length,
      itemBuilder: (context, index) {
        return ListTile(
          title: Text(_data[index]['name']),
          subtitle: Text(_data[index]['description']),
        );
      },
    );
  }
}