本文介绍了带有Flutter和Firestore的GridView的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我正在尝试从云Firestore记录中创建一个简单的GridView.我已经看了很多视频教程,但是都没有成功.这是代码:
I`m trying to make a simple GridView from a cloud firestore record. I've followed a lot of video tutorials but without success. Here's the code:
import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
class EventList extends StatefulWidget {
@override
EventListState createState() => new EventListState();
}
class EventListState extends State<EventList> {
@override
Widget build(BuildContext context) {
return StreamBuilder(
stream: Firestore.instance.collection('events_flutter').snapshots(),
builder: (BuildContext context, DocumentSnapshot snapshot) {
if (!snapshot.hasData) {
return Center(child: const Text('Loading events...'));
}
return GridView.builder(
gridDelegate:
SliverGridDelegateWithFixedCrossAxisCount(crossAxisCount: 2),
itemBuilder: (BuildContext context, int index) {
return Text(snapshot['event_name']);
},
itemCount: snapshot.data.documents.length,
);
},
);}}
这是当悬停在"builder:(BuildContext上下文,DocumentSnapshot快照)"上时的错误消息.有人可以帮助我了解发生了什么事吗?
And this is the error message when hovering on "builder: (BuildContext context, DocumentSnapshot snapshot)".Could anybody help me understand what is going on?
非常感谢.
推荐答案
您应将快照
的类型从 DocumentSnapshot
替换为 AsyncSnapshot
...
builder: (BuildContext context, AsyncSnapshot snapshot) {
if (!snapshot.hasData) {
return Center(child: const Text('Loading events...'));
}
...
而且,您可能要替换此行:
And also, you might want to replace this line:
return Text(snapshot['event_name']);
对此:
return Text(snapshot.data.documents[index]['event_name']);
这篇关于带有Flutter和Firestore的GridView的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!