数据显示出来，我只有白屏
数据显示出来，我只有白屏
提问于 2020-08-31 03:22:28
我创建了一个聊天应用程序，并尝试调用firebase中的数据以显示在屏幕上，但只出现了白色屏幕，我仍在学习flutter和使用firestore_cloud
import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
class ChatScreen extends StatelessWidget {
@override
Widget build(BuildContext context) {
CollectionReference users = FirebaseFirestore.instance
.collection('chats/lTHEN8VkO7uVAtbeY25R/messeges');
return Scaffold(
body: StreamBuilder(
stream: users.snapshots(),
builder: (ctx, code) {
if (code.connectionState == ConnectionState.waiting) {
return Center(
child: CircularProgressIndicator(),
);
}
final documents = code.data.documents;
return ListView.builder(
itemBuilder: (ctx, index) => Container(
child: Text(documents[index]['text']),
padding: EdgeInsets.all(8),
),
itemCount: documents.length,
);
},
),
floatingActionButton: FloatingActionButton(
onPressed: () {},
child: Icon(Icons.add),
),
);
}
} 回答 1
Stack Overflow用户
发布于 2020-08-31 03:31:13
尝尝这个,
import 'package:firebase_core/firebase_core.dart';
import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
CollectionReference users = FirebaseFirestore.instance
.collection('chats/lTHEN8VkO7uVAtbeY25R/messeges');
class ChatScreen extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Scaffold(
body: StreamBuilder(
stream: users.snapshots(),
builder: (context, snapshot){
if (snapshots.connectionState == ConnectionState.active &&
snapshots.hasData) {
print(snapshots.data);
return ListView.builder(
itemCount: snapshots.data.length,
itemBuilder: (BuildContext context, int index) {
var doc=snapshots.data[index];
Map data= doc.data; // this is your data which is probably a map
return Text(
data[index]['text']
);
},
);
} else {
return Center(child: CircularProgressIndicator());
}
},
),
);
}
} 页面原文内容由Stack Overflow提供。腾讯云小微IT领域专用引擎提供翻译支持
原文链接：
https://stackoverflow.com/questions/63661297
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