基于用户角色的不同屏幕不起作用

Question

嗨，我是Flutter的新手，正在开发一款预约应用程序，该应用程序需要筛选两种类型的用户，即患者和医生。

class DashboardPage extends StatefulWidget {
@override
_DashboardPageState createState() => _DashboardPageState();
}
class _DashboardPageState extends State<DashboardPage> {
UserProvider userProvider;
final AuthMethods _authMethods = AuthMethods();
@override
void initState() {
super.initState();
SchedulerBinding.instance.addPostFrameCallback((_) async {
userProvider = Provider.of<UserProvider>(context, listen: false);
await userProvider.refreshUser();
_authMethods. getUserDetails();
});
}

User user = User();
@override
Widget build(BuildContext context) {
if (user.role == 'patient') {
return PatientHomePage();
}
else if (user.role == 'doctor') {
return DoctorHomePage();}
return Container(color: Colors.red,);
}
}

角色变量在另一个dart文件中定义：

class User {   String uid;   String name;   String email;   String role = "patient";   String profilePhoto;    User({     this.uid,     this.name,     this.email,     this.role,     this.profilePhoto,   });   ........... }

默认值"；病人"；当用户登录时分配给它。Future<void> addDataToDb(FirebaseUser currentUser) async { User user = User( uid: currentUser.uid, email: currentUser.email, name: currentUser.displayName, profilePhoto: currentUser.photoUrl, role: "patient"); firestore .collection(USERS_COLLECTION) .document(currentUser.uid) .setData(user.toMap(user)); }所有这些都发生在另一个dart文件中

但这个逻辑并没有像预期的那样工作，因为它只显示了手机上的红色屏幕，这意味着从firebase获取user.role存在一些问题。请帮帮我…

Answer 1

class DashboardPage extends StatefulWidget {
@override
_DashboardPageState createState() => _DashboardPageState();
}
class _DashboardPageState extends State<DashboardPage> {
UserProvider userProvider;
final AuthMethods _authMethods = AuthMethods();
User user = User();
@override
void initState() {
super.initState();
SchedulerBinding.instance.addPostFrameCallback((_) async {
userProvider = Provider.of<UserProvider>(context, listen: false);
/// This method is future method so it might happen that after widget render you are getting response.
await userProvider.refreshUser();
/// seState will rebuild your widget with new user details
setState(() {
user = _authMethods. getUserDetails();
});
});
}

@override
Widget build(BuildContext context) {
if (user.role == 'patient') {
return PatientHomePage();
}
else if (user.role == 'doctor') {
return DoctorHomePage();}
return Container(color: Colors.red,);
}
}