如何使用 Flutter 从 Firebase 检索电话号码

Question

如何在Firebase中检索电话身份验证期间使用的电话号码并使用颤振显示它，我尝试了以下方法，但它对我不起作用：

FirebaseAuth.instance.currentUser().then((user) {
_userId = user.uid;
_phone = user.phoneNumber;
});

这是我的完整代码

class HomePageState extends State<HomeScreen>{
String _userId,_phone;
@override
Widget build(BuildContext context) {
FirebaseAuth.instance.currentUser().then((user) {
_userId = user.uid;
_phone = user.phoneNumber;
});
var myGridView = new GridView.builder(
itemCount: services.length,
gridDelegate: new SliverGridDelegateWithFixedCrossAxisCount(
crossAxisCount: 3,
// childAspectRatio: (itemWidth / itemHeight),
),
itemBuilder: (BuildContext context, int index) {
return FlatButton(
child: Padding(
padding: const EdgeInsets.all(0.0),
// child:new Card(
//elevation: 5.0,
child: new Container(
alignment: Alignment.centerLeft,
child: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: [
new Text(_userId), 
],
),
),
),
),
onPressed: () {
String catgry = services[index];
if (catgry == "coming soon") {
showDialog(
barrierDismissible: false,
context: context,
child: new CupertinoAlertDialog(
title: new Column(
children: <Widget>[
new Text("This feature is coming soon"),
new Icon(
Icons.favorite,
color: Colors.red,
),
],
),
// content: new Text( services[index]),
actions: <Widget>[
new FlatButton(
onPressed: () {
Navigator.of(context).pop();
},
child: new Text("OK"))
],
));
} else {
Navigator.push(
context,
new MaterialPageRoute(
builder: (context) => Details(catgry,phone1)));
}
},
);
},
);
return new Scaffold(
appBar: new AppBar(
backgroundColor: Colors.black,
title: Text("Appbar", style: TextStyle(color: Colors.white),),
),),
body: myGridView,
bottomNavigationBar: CustomBottomBar(),
);
}
}

Answer 1

你可以使用 async/await 来做到这一点，一旦你得到数据，你就可以调用setState((

String phone;
@override
void initState(){
super.initState();
getPhone();
}
getPhone() async{
FirebaseUser currentUser = await FirebaseAuth.instance.currentUser();
setState(() {
phone=currentUser.phoneNumber;
});
}

Answer 2

当你正在使用StatefulWidget时，你可以创建一个getUser函数，该函数将更新userId和电话，然后在initState中调用该函数。在获取值时，还要添加一个带有Center(child: CircularProgressIndicator())的加载屏幕

class _HomeScreenState extends State<HomeScreen> {
String _userId,_phone;
bool loading = true;

getUser(){
FirebaseAuth.instance.currentUser().then((user) {
_userId = user.uid;
_phone = user.phoneNumber;
loading = false;
setState(() {});
});
}
@override
void initState() {
super.initState();
getUser();
}

@override
Widget build(BuildContext context) {
var myGridView = new GridView.builder(
itemCount: services.length,
gridDelegate: new SliverGridDelegateWithFixedCrossAxisCount(
crossAxisCount: 3,
// childAspectRatio: (itemWidth / itemHeight),
),
itemBuilder: (BuildContext context, int index) {
return FlatButton(
child: Padding(
padding: const EdgeInsets.all(0.0),
// child:new Card(
//elevation: 5.0,
child: new Container(
alignment: Alignment.centerLeft,
child: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: [
new Text(_userId),
],
),
),
),
),
onPressed: () {
String catgry = services[index];
if (catgry == "coming soon") {
showDialog(
barrierDismissible: false,
context: context,
child: new CupertinoAlertDialog(
title: new Column(
children: <Widget>[
new Text("This feature is coming soon"),
new Icon(
Icons.favorite,
color: Colors.red,
),
],
),
// content: new Text( services[index]),
actions: <Widget>[
new FlatButton(
onPressed: () {
Navigator.of(context).pop();
},
child: new Text("OK"))
],
));
} else {
Navigator.push(
context,
new MaterialPageRoute(
builder: (context) => Details(catgry,phone1)));
}
},
);
},
);
return new Scaffold(
appBar: new AppBar(
backgroundColor: Colors.black,
title: Text("Appbar", style: TextStyle(color: Colors.white),),
),
body: loading?Center(child: CircularProgressIndicator()):myGridView,
bottomNavigationBar: CustomBottomBar(),
);
}
}