【发布时间】：2020-06-26 10:09:55
【问题描述】：
我正在尝试制作一个屏幕，用户可以在其中添加一个人的生日，但在另一个时刻，同一屏幕应该从 Firebase 加载数据并在TextFields 中显示加载的值。我正在使用BLoC 和流来执行此操作。我可以正确地从 Firebase 加载数据，并在每个TextField 中使用StreamBuilders 将其传递到屏幕，但是即使流包含正确的值，这些值也没有显示。在同一页面中，我使用一些DropdownButtons 来获取可选数据，它们接收并显示值就好了。我不确定我做错了什么。
这是每个TextField的代码：
class InputField extends StatelessWidget {
final IconData icon;
final String hint;
final bool obscure;
final TextInputType type;
final Stream<String> stream;
final Function(String) onChanged;
InputField({this.icon, this.hint, this.obscure, this.type, this.stream, this.onChanged});
@override
Widget build(BuildContext context) {
return StreamBuilder<String>(
stream: stream,
builder: (context, snapshot) {
return TextField(
onChanged: onChanged,
keyboardType: type != null ? type : null,
decoration: InputDecoration(
icon: icon == null ? null : Icon(icon, color: Colors.white,),
hintText: hint,
hintStyle: TextStyle(color: Colors.white),
focusedBorder: UnderlineInputBorder(
borderSide: BorderSide(color: Theme.of(context).primaryColor)
),
contentPadding: EdgeInsets.only(
left: 5,
right: 30,
bottom: 30,
top: 30
),
errorText: snapshot.hasError ? snapshot.error : null
),
style: TextStyle(color: Colors.white),
obscureText: obscure,
);
}
);
}
}
这是我初始化输入类型的地方：
return Padding(
padding: EdgeInsets.all(16.0),
child: SingleChildScrollView(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
InputField(
icon: Icons.person_outline,
hint: "Nome do aniversariante",
obscure: false,
type: TextInputType.text,
stream: _birthdayBloc.outName,
onChanged: _birthdayBloc.changeName,
),
InputField(
icon: Icons.phone,
hint: "Telefone",
obscure: false,
type: TextInputType.text,
stream: _birthdayBloc.outPhone,
onChanged: _birthdayBloc.changePhone,
),
InputField(
icon: Icons.email,
hint: "E-mail",
obscure: false,
type: TextInputType.text,
stream: _birthdayBloc.outEmail,
onChanged: _birthdayBloc.changeEmail,
),
DropdownWidget(
isCenter: false,
icon: Icons.list,
arrowIcon: Icons.keyboard_arrow_down,
hint: "Selecione uma categoria",
items: _birthdayBloc.getCategoryList(),
stream: _birthdayBloc.outCategory,
onChanged: _birthdayBloc.changeCategory,
),
DropdownWidget(
isCenter: false,
icon: Icons.notifications,
arrowIcon: Icons.keyboard_arrow_down,
hint: "Selecione a notificação",
items: _birthdayBloc.getNotificationList(),
stream: _birthdayBloc.outNotification,
onChanged: _birthdayBloc.changeNotification,
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
Expanded(
flex: 5,
child: DropdownWidget(
isCenter: false,
label: "Mês",
icon: Icons.calendar_today,
arrowIcon: Icons.keyboard_arrow_down,
hint: "Selecione o mês",
items: _birthdayBloc.getMonthsList(),
stream: _birthdayBloc.outMonth,
onChanged: _birthdayBloc.changeMonth,
),
),
Expanded(
flex: 5,
child: DropdownWidget(
isCenter: false,
label: "Dia",
arrowIcon: Icons.keyboard_arrow_down,
hint: "Selecione o dia",
items: _birthdayBloc.getDaysList(),
stream: _birthdayBloc.outDay,
onChanged: _birthdayBloc.changeDay,
),
),
],
),
DropdownWidget(
isCenter: false,
label: "Ano de nascimento",
icon: Icons.perm_contact_calendar,
arrowIcon: Icons.keyboard_arrow_down,
hint: "Selecione o ano",
items: _birthdayBloc.getYearsList(),
stream: _birthdayBloc.outYear,
onChanged: _birthdayBloc.changeYear,
valueController: 'Não sei'
),
这是在屏幕加载时从Firebase检索数据的代码：
Future<void> _loadSelectedBirthday(personId) async {
String _userUid = await _getCurrentUserUid();
await _firestore.collection('birthdays').document(_userUid).collection('birthdays').document(personId).get()
.then((document) {
_nameController.add(document.data["name"]);
_phoneController.add(document.data["phone"]);
_emailController.add(document.data["email"]);
_categoryController.add(document.data["category"]);
_notificationController.add(document.data["notification"]);
_monthController.add(document.data["month"]);
_dayController.add(document.data["day"]);
_yearController.add(document.data["year"]);
print(_nameController.value);
print(_phoneController.value);
print(_emailController.value);
print(_categoryController.value);
print(_notificationController.value);
print(_monthController.value);
print(_dayController.value);
print(_yearController.value);
_stateController.add(BirthdayState.READY);
}).catchError((error) {
print('ERROR => $error');
});
}
我从上面的打印中得到的输出是：
I/flutter (10907): Person Name
I/flutter (10907): 62999991234
I/flutter (10907): someemail@gmail.com
I/flutter (10907): Familiar
I/flutter (10907): No dia
I/flutter (10907): 3
I/flutter (10907): 25
I/flutter (10907): 1996
这是来自应用程序屏幕的打印：
【问题讨论】：