及时从Firestore检索数据 [英] Retrieving Data From Firestore in time
本文介绍了及时从Firestore检索数据的处理方法，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
我在互联网上四处寻找解决问题的方法，但找不到任何解决方案.我在Firestore中使用Flutter来制作应用程序.我要这样做，以便用户在顶部登录应用程序时显示其名称(简单右侧).我可以从Firestore获取数据:
I have looked all over the internet for how to fix this problem and I can't find a solution anywhere. I am using flutter with firestore to make an app. I want to make it so when the user logins into the app at the top shows their name (simple right). I can get data from firestore:
Future<void> getName() async {
print("Attemping to get name!");
final firestoreInstance = await FirebaseFirestore.instance;
FirebaseAuth auth = FirebaseAuth.instance;
String uid = auth.currentUser.uid.toString();
await firestoreInstance.collection("Users").doc(uid).get().then((value) {
print("Name: " + value.data()["firstName"]);
info.firstName=((value.data()["firstName"]));
})
class info {
static String firstName;
}
，但为时已晚，因此该应用仅在屏幕上显示"Welcome back"您可以在此处看到，而不是欢迎回来，康纳"如此处所示
but it comes in too late so the app just says "Welcome back" As you can see here and not "Welcome back, Connor" As seen here
当我在控制台中查看时，该函数确实运行，但程序未等待它，并继续导致null.
When I look in the console the function does run but the program doesn't wait for it and continues resulting in a null.
谢谢
根据请求的用户界面代码进行
EDIT as requested UI code:
class Home extends StatelessWidget {
final DatabaseReference = FirebaseDatabase.instance;
final FirebaseAuth auth = FirebaseAuth.instance;
static String firstName;
static String lastName;
static String email;
static String companyName;
static bool isNewAccount = false;
static String name = "Welcome back";
Home();
@override
Widget build(BuildContext context) {
final User user = auth.currentUser;
final uid = user.uid;
final ref = DatabaseReference.reference();
if (isNewAccount == true) {
userSetup(firstName, lastName, email, companyName);
isNewAccount = false;
}
getName(); //does get the name from the database but name will error out as it doesn't get the name fast enough (or that's what I think)
name= "Welcome back, "+info.firstName;
return WillPopScope(
onWillPop: () async => false,
child: MaterialApp(
debugShowCheckedModeBanner: false,
home: Scaffold(
backgroundColor: Colors.cyan,
body: SingleChildScrollView(
child: Container(
margin:
EdgeInsets.only(top: MediaQuery.of(context).size.height / 16),
child: Column(
children: [
Container(
margin: EdgeInsets.only(bottom: 10),
child: Text(
name,
textAlign: TextAlign.center,
style: new TextStyle(
color: Colors.white,
fontSize: MediaQuery.of(context).size.width / 16,
),
),
),
Container(
width: 260,
height: 125,
child: RaisedButton(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(20.0),
),
child: Text(
"CHECK-IN",
style: new TextStyle(
color: Colors.white,
fontSize: 40.0,
),
),
color: Colors.grey[850],
onPressed: () {
Navigator.push(context,
MaterialPageRoute(builder: (context) => Checkin()));
},
),
),
Container(
width: 260,
height: 140,
padding: EdgeInsets.only(top: 20),
child: RaisedButton(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(20.0),
),
child: Text(
"CHECK-OUT",
style: new TextStyle(
color: Colors.white,
fontSize: 38.0,
),
),
color: Colors.grey[850],
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => Checkout()));
},
),
),
Container(
margin: EdgeInsets.only(top: 55),
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Container(
padding: EdgeInsets.only(right: 20),
child: Text(
"Sign out: ",
style: new TextStyle(
fontSize: 15.0,
fontWeight: FontWeight.bold,
),
),
),
Container(
child: RaisedButton(
child: Text(
"SIGN OUT",
style: new TextStyle(
fontSize: 14.0,
color: Colors.white,
),
),
color: Colors.grey[700],
onPressed: () {
context.read<AuthenticationService>().signOut();
//return MyApp();
},
),
)
],
),
),
Container(
margin: EdgeInsets.only(top: 10),
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Container(
padding: EdgeInsets.only(right: 20),
child: Text(
"View Stats: ",
style: new TextStyle(
fontSize: 15.0,
fontWeight: FontWeight.bold,
),
),
),
Container(
child: RaisedButton(
child: Text(
"STATS",
style: new TextStyle(
fontSize: 14.0,
color: Colors.white,
),
),
color: Colors.grey[700],
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => Stats()));
},
),
),
],
),
),
Container(
margin: EdgeInsets.only(top: 10),
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Container(
padding: EdgeInsets.only(right: 20),
child: Text(
"View Profile: ",
style: new TextStyle(
fontSize: 15.0,
fontWeight: FontWeight.bold,
),
),
),
Container(
child: RaisedButton(
child: Text(
"PROFILE",
style: new TextStyle(
fontSize: 14.0,
color: Colors.white,
),
),
color: Colors.grey[700],
onPressed: () {
/*Navigator.push(
context,
MaterialPageRoute(
builder: (context) => Stats()));*/
},
),
),
],
),
),
Container(
width: 240,
height: 55,
margin: EdgeInsets.only(
top: MediaQuery.of(context).size.height / 12),
child: RaisedButton(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(20.0),
),
child: Text(
"EMERGENCY REPORT",
style: new TextStyle(
color: Colors.white,
fontSize: 20.0,
),
),
color: Colors.grey[700],
onPressed: () {
Navigator.push(context,
MaterialPageRoute(builder: (context) => EmergencyReport()));
},
),
),
],
),
),
),
),
),
);
}
static getAccountDetails(
String firstName1, String lastName1, String email1, String companyName1) {
firstName = firstName1;
lastName = lastName1;
email = email1;
companyName = companyName1;
isNewAccount = true;
}
static getFirstName(String nameFirst) {
name = "Welcome back, "+nameFirst;
}
}
推荐答案
FutureBuilder<DocumentSnapshot>(
future: firestoreInstance.collection("Users").doc(uid).get(),
builder: (_,snap){
return snap.hasData ? Text(snap.data.data()["firstName"]):CircularProgressIndicator();
},)
这篇关于及时从Firestore检索数据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！
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