使用flutter从firestore获取数据以获取基于角色的主视图

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

class RoleBasedView extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return StreamBuilder<QuerySnapshot>(
      stream: Firestore.instance.collection('users').where('role', isEqualTo: 'admin').snapshots(),
      builder: (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
        if (snapshot.hasError) {
          return Text('Error: ${snapshot.error}');
        }

        if (snapshot.connectionState == ConnectionState.waiting) {
          return Text('Loading...');
        }

        return ListView(
          children: snapshot.data.documents.map((DocumentSnapshot document) {
            return ListTile(
              title: Text(document['name']),
              subtitle: Text(document['email']),
            );
          }).toList(),
        );
      },
    );
  }
}