在flutter中使用流生成器时,我不断收到轻微的null错误 [英] I keep getting a slight null error when using stream builder in flutter
本文介绍了在flutter中使用流生成器时,我不断收到轻微的null错误的处理方法,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
在显示我的商品之前,我总是收到一个轻微的null错误.请问我能否获得使用streambuilder的最佳方式的帮助,而不会遇到任何错误?
I keep getting a slight null error before displaying my items. Please can I get help on the best way to use streambuilder without encountering any error?
推荐答案
使用 ConnectionState
:
StreamBuilder(
stream: Firestore.instance.collection('stores').document(currentUserUID).snapshots(),
builder: (context, AsyncSnapshot<DocumentSnapshot> snapshot) {
if (snapshot.connectionState == ConnectionState.done) {
return ListView.builder(
shrinkWrap: true,
itemCount: 1,
itemBuilder: (BuildContext context, int index) {
return ListTile(
contentPadding: EdgeInsets.all(8.0),
title: Text(snapshot.data.data["about"]),
leading: Text(
snapshot.data.data["location"],
));
});
} else if (snapshot.connectionState == ConnectionState.none) {
return Text("No data");
}
return CircularProgressIndicator();
},
),
https://api.flutter.dev/flutter/widgets/ConnectionState-class.html
这篇关于在flutter中使用流生成器时,我不断收到轻微的null错误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IT屋!
查看全文