DropdownButton selection calls the onValidate functions of other fields in Flutter - flutter

Question

Not sure what I'm missing. When selecting the value of drop-down, form onVaidate() fired which hence my other fields are showing the error. How can I stop it? Here is the code
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,
),
))
],
))),
);
}

Answer 1

Call a method to return null in the validate fucntion all the other fields. That will clear the validation. It's a fix, but doesn't solve the problem.
There seems to be nothing wrong with the code above, can you add the code for the other fields too?
EDIT:
The reason all the other fields validate is because of the autovalidate: true property of the parent Form widget. Remove it and wrap each TextFormField with a Form with different keys.
For example, your TextFormField should look as follows:
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',
),
),
),
Wrap it with a Form, _formKey is declared as
List<GlobalObjectKey<FormState>> _formKey = new List(number_of_keys);
Call the respective setState like so:
_formKey[position].currentState.setState((){});
And don't forget to remove the parent Form widget.