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[英]Selection of Item in DropdownButton causes Flutter to throw error
[英]DropdownButton selection calls the onValidate functions of other fields in Flutter
不知道我錯過了什么。 選擇下拉列表的值時,表單onVaidate()
被觸發,因此我的其他字段顯示錯誤。 我怎樣才能阻止它? 這是代碼
Widget build(BuildContext context) { // return Scaffold( // appBar: AppBar(title: Text("Registration")), // body: Center(child: Text(widget.user.displayName)), // );
FirebaseUser user = widget.user;
return Scaffold(
key: _scaffoldKey,
appBar: AppBar(
title: Text("Registration"),
),
body: SafeArea(
top: false,
bottom: false,
child: Form(
key: _formKey,
autovalidate: true,
child: ListView(
padding: const EdgeInsets.symmetric(horizontal: 16.0),
children: <Widget>[
TextFormField(
validator: (value) => value.isEmpty ? 'Name is Required' : null,
decoration: const InputDecoration(
icon: const Icon(Icons.person),
hintText: 'Enter your first and last name',
labelText: 'Name',
),
),
TextFormField(
decoration: const InputDecoration(
icon: const Icon(Icons.phone),
hintText: 'Enter a phone number',
labelText: 'Phone',
),
initialValue: user.phoneNumber,
enabled: user.phoneNumber == null,
keyboardType: TextInputType.phone,
validator: (value) => value.isEmpty ? 'Phone number is Required' : null
// inputFormatters: [
// WhitelistingTextInputFormatter.digitsOnly,
// ],
),
TextFormField(
decoration: const InputDecoration(
icon: const Icon(Icons.email),
hintText: 'Enter a email address',
labelText: 'Email',
),
initialValue: user.email,
enabled: user.email == null,
validator: (value) => value.isEmpty ? 'Email is Required' : null,
keyboardType: TextInputType.emailAddress,
),
TextFormField(
decoration: const InputDecoration(
icon: const Icon(Icons.remove_red_eye),
hintText: 'Enter the Password',
labelText: 'Password',
),
keyboardType: TextInputType.text,
obscureText: true,
validator: (value) => value.isEmpty ? 'Password is Required' : null
),
FormField(
builder: (FormFieldState state) {
return InputDecorator(
decoration: InputDecoration(
icon: const Icon(Icons.card_membership),
labelText: 'ID Type',
),
isEmpty: _profile.govId == null,
child: DropdownButtonHideUnderline(
child: DropdownButton(
value: _profile.govId,
isDense: true,
onChanged: (String newValue) {
setState(() {
_profile.govId = newValue;
state.didChange(newValue);
});
},
items: _govtIds.map((String value) {
return DropdownMenuItem(
value: value,
child: Text(value),
);
}).toList(),
),
),
);
},
),
TextFormField(
decoration: const InputDecoration(
icon: const Icon(Icons.confirmation_number),
hintText: 'Enter your Governmenr ID number',
labelText: 'ID Number',
),
keyboardType: TextInputType.datetime,
validator: (value) => value.isEmpty ? 'ID Number is Required' : null
),
FormField(
builder: (FormFieldState state) {
return InputDecorator(
decoration: InputDecoration(
icon: const Icon(Icons.business),
labelText: 'Block Info',
),
isEmpty: _profile.block == null,
child:
// Column(children: [RadioListTile(title: Text("A")),RadioListTile(title: Text("B"))]),
// Radio(
// value: 0,
// groupValue: _blocks,
// onChanged: (value){}),
DropdownButtonHideUnderline(
child:
DropdownButton(
value: _profile.block,
isDense: true,
onChanged: (String newValue) {
setState(() {
_profile.block = newValue;
state.didChange(newValue);
});
},
items: _blocks.map((String value) {
return DropdownMenuItem(
value: value,
child: Text(value),
);
}).toList(),
),
),
);
},
),
TextFormField(
decoration: const InputDecoration(
icon: const Icon(Icons.home),
hintText: 'Enter your Flat number',
labelText: 'Flat number',
),
inputFormatters: [LengthLimitingTextInputFormatter(3)],
validator: (value) {
if (value.isEmpty) {
return 'Flat number is Required';
} else if (_profile.isValidHouseNumber() == false) {
return 'Invalid flat number';
} else {
return null;
}
},
keyboardType: TextInputType.number,
onChanged:(value) {
_profile.houseNo = value;
},
),
Padding(
padding: EdgeInsets.fromLTRB(38.0, 30.0, 0.0, 0.0),
child: SizedBox(
height: 50.0,
child: FlatButton(
// elevation: 5.0,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(10.0)),
color: Colors.green,
child: Text('Submit',
style: TextStyle(fontSize: 20.0, color: Colors.white)),
onPressed: _validateAndSubmit,
),
))
],
))),
);
}
在驗證功能中調用一個方法返回 null 所有其他字段。 這將清除驗證。 這是一個修復,但不能解決問題。
上面的代碼好像沒什么問題,能不能把其他字段的代碼也加一下?
編輯:
所有其他字段驗證的原因是父表單小部件的autovalidate: true
屬性。 刪除它並使用具有different keys
的 Form 包裝每個 TextFormField 。
例如,您的TextFormField
應如下所示:
Form(
key: _formKey[0],
child: TextFormField(
validator: (value) => value.isEmpty ? 'Name is Required' : null,
decoration: const InputDecoration(
icon: const Icon(Icons.person),
hintText: 'Enter your first and last name',
labelText: 'Name',
),
),
),
用表單包裹它,_formKey 被聲明為
List<GlobalObjectKey<FormState>> _formKey = new List(number_of_keys);
像這樣調用相應的 setState:
_formKey[position].currentState.setState((){});
並且不要忘記刪除父表單小部件。
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