Блог

Поэтому я хочу создавать сообщения об ошибках на странице входа, но сообщения не появляются или не очень хорошо работают как с сообщениями об ошибках электронной почты, так и с сообщениями об ошибках пароля. Всякий раз, когда я нажимал на кнопку «ВОЙТИ», я заставлял ее всегда переходить на следующую страницу, а этого не должно было быть. Вот мой код:

ФОРМА ДЛЯ ВХОДА В СИСТЕМУ

 class sign_in_form extends StatefulWidget {  const sign_in_form({Key? key}) : super(key: key);   @override  _sign_in_formState createState() =gt; _sign_in_formState(); }  class _sign_in_formState extends Statelt;sign_in_formgt; {  final _formKey = GlobalKeylt;FormStategt;();  String? email;  String? password;   final Listlt;String?gt; errors = [];   void addError ({String? error}) {  if (!errors.contains(error)) {  setState(() {  errors.add(error);  });  }  }   void removeError ({String? error}) {  if (!errors.contains(error)) {  setState(() {  errors.remove(error);  });  }  }   @override  Widget build(BuildContext context) {  return Form(  key: _formKey,  child: Column(  children: lt;Widgetgt;[  buildEmailFormField(),  SizedBox(height: getProportionateScreenHeight(20)),  buildPasswordFormField(),  SizedBox(height: getProportionateScreenHeight(20)),  errors_form(errors: errors),  SizedBox(height: getProportionateScreenHeight(20)),  splash_button(  press: () {  if (_formKey.currentState!.validate()) {  _formKey.currentState!.save();  }  },  ),  ],  ),  );  }  TextFormField buildEmailFormField() {  return TextFormField(  keyboardType: TextInputType.emailAddress,  onSaved: (newValue) =gt; email = newValue,  onChanged: (value) {  if (value.isNotEmpty) {  removeError(error: "Please Enter your email");  }  else if (emailValidatorRegExp.hasMatch(value)) {  removeError(error: "Please Enter Valid Email");  }  return;  },  validator: (value) {  if (value!.isEmpty) {  addError(error: "Please Enter your email");  return "";  }  else if (!emailValidatorRegExp.hasMatch(value)) {  addError(error: "Please Enter Valid Email");  return "";  }  return value;  },  decoration: const InputDecoration(  labelText: "Email",  hintText: "Enter your email",  floatingLabelBehavior: FloatingLabelBehavior.always,  suffixIcon: Padding(  padding: EdgeInsets.fromLTRB(0, 20, 20, 20),  child: Icon(Icons.email),  ),  ),  );  }  TextFormField buildPasswordFormField() {  return TextFormField(  obscureText: true,  onSaved: (newValue) =gt; password = newValue,  onChanged: (value){  if (value.isNotEmpty) {  removeError(error: "Please Enter your password");  }  else if (value.length gt;= 8) {  removeError(error: "Password is too short");  }  return;  },  validator: (value){  if (value!.isEmpty) {  addError(error: "Please Enter your password");  return "";  }  else if (!emailValidatorRegExp.hasMatch(value)) {  addError(error: "Password is too short");  return "";  }  return null;  },  decoration: const InputDecoration(  labelText: "Password",  hintText: "Enter your password",  floatingLabelBehavior: FloatingLabelBehavior.always,  suffixIcon: Padding(  padding: EdgeInsets.fromLTRB(0, 20, 20, 20),  child: Icon(Icons.lock),  ),  ),  );  } }    

МОЯ ФОРМА ОШИБКИ

 class errors_form extends StatelessWidget {  const errors_form({Key? key, required this.errors,}) : super(key: key);  final Listlt;String?gt; errors;   @override  Widget build(BuildContext context) {  return Column(  children: List.generate(  errors.length, (index) =gt; form_error_text(errors: errors[index]!)),  );  }  Row form_error_text ({required String errors}) {  return Row(  children: [  SvgPicture.asset(  "assets/icons/Error.svg",  height: getProportionateScreenWidth(14),  width: getProportionateScreenWidth(14),  ),  SizedBox(width: getProportionateScreenWidth(14)),  Text(errors),  ],  );  } }  

Please refer to below example code of error messages handling

 class MainScreen extends StatelessWidget {  MainScreen({Key key}) : super(key: key);   final TextEditingController emailController = TextEditingController();  final FocusNode emailFocus = FocusNode();  final TextEditingController pswdController = TextEditingController();  final FocusNode pswdFocus = FocusNode();  final _validationKey = GlobalKeylt;FormStategt;();   int validateEmail(String emailAddress) {  String patttern =  r"^[a-zA-Z0-9.!#$%amp;'* /=?^_`{|}~-] @[a-zA-Z0-9](?:[a-zA-Z0-9-]"  r"{0,253}[a-zA-Z0-9])?(?:.[a-zA-Z0-9](?:[a-zA-Z0-9-]"  r"{0,253}[a-zA-Z0-9])?)*$";  RegExp regExp = new RegExp(patttern);  if (emailAddress.isEmpty || emailAddress.length == 0) {  return 1;  } else if (!regExp.hasMatch(emailAddress)) {  return 2;  } else {  return 0;  }  }   int validatePassword(String pswd) {  if (pswd.isEmpty || pswd.length == 0) {  return 1;  } else if (pswd != null amp;amp; pswd.isNotEmpty amp;amp; pswd.length lt;= 8) {  return 2;  } else {  return 0;  }  }   @override  Widget build(BuildContext context) {  return Scaffold(  appBar: AppBar(  backgroundColor: Colors.lightBlue,  automaticallyImplyLeading: true,  leading: Icon(  Icons.arrow_back,  ),  title: Text("Example"),  centerTitle: true,  ),  body: Container(  padding: EdgeInsets.all(15.0),  child: Column(  children: [  Form(  key: _validationKey,  child: Column(  children: [  /* Email */  TextFormField(  autovalidateMode: AutovalidateMode.onUserInteraction,  /* autovalidate is disabled */  controller: emailController,  inputFormatters: [  FilteringTextInputFormatter.deny(RegExp(r"ss")),  FilteringTextInputFormatter.deny(RegExp(  r'(u00a9|u00ae|[u2000-u3300]|ud83c[ud000-udfff]|ud83d[ud000-udfff]|ud83e[ud000-udfff])')),  ],  keyboardType: TextInputType.text,  maxLength: 160,  onChanged: (val) {},  maxLines: 1,  validator: (value) {  int res = validateEmail(value);  if (res == 1) {  return "Please enter your email address";  } else if (res == 2) {  return "Please enter valid email address";  } else {  return null;  }  },  focusNode: emailFocus,  autofocus: false,  decoration: InputDecoration(  errorMaxLines: 3,  counterText: "",  filled: true,  fillColor: Colors.white,  focusedBorder: OutlineInputBorder(  borderRadius: BorderRadius.all(Radius.circular(4)),  borderSide: BorderSide(  width: 1,  color: Color(0xffE5E5E5),  ),  ),  disabledBorder: OutlineInputBorder(  borderRadius: BorderRadius.all(Radius.circular(4)),  borderSide: BorderSide(  width: 1,  color: Color(0xffE5E5E5),  ),  ),  enabledBorder: OutlineInputBorder(  borderRadius: BorderRadius.all(Radius.circular(4)),  borderSide: BorderSide(  width: 1,  color: Color(0xffE5E5E5),  ),  ),  border: OutlineInputBorder(  borderRadius: BorderRadius.all(Radius.circular(4)),  borderSide: BorderSide(  width: 1,  ),  ),  errorBorder: OutlineInputBorder(  borderRadius: BorderRadius.all(Radius.circular(4)),  borderSide: BorderSide(  width: 1,  color: Colors.red,  )),  focusedErrorBorder: OutlineInputBorder(  borderRadius: BorderRadius.all(Radius.circular(4)),  borderSide: BorderSide(  width: 1,  color: Colors.red,  ),  ),  hintText: "Enter your email" ?? "",  ),  ),  SizedBox(  height: 15.0,  ),   /* Password */  TextFormField(  autovalidateMode: AutovalidateMode.onUserInteraction,  /* autovalidate is disabled */  controller: pswdController,  inputFormatters: [  FilteringTextInputFormatter.deny(RegExp(r"ss")),  FilteringTextInputFormatter.deny(RegExp(  r'(u00a9|u00ae|[u2000-u3300]|ud83c[ud000-udfff]|ud83d[ud000-udfff]|ud83e[ud000-udfff])')),  ],  keyboardType: TextInputType.text,  maxLength: 160,  onChanged: (val) {},  obscureText: true,  maxLines: 1,  validator: (value) {  int res = validatePassword(value);  if (res == 1) {  return "Please enter password";  } else if (res == 2) {  return "Please enter minimum 9 characters";  } else {  return null;  }  },  focusNode: pswdFocus,  autofocus: false,  decoration: InputDecoration(  errorMaxLines: 3,  counterText: "",  filled: true,  fillColor: Colors.white,  focusedBorder: OutlineInputBorder(  borderRadius: BorderRadius.all(Radius.circular(4)),  borderSide: BorderSide(  width: 1,  color: Color(0xffE5E5E5),  ),  ),  disabledBorder: OutlineInputBorder(  borderRadius: BorderRadius.all(Radius.circular(4)),  borderSide: BorderSide(  width: 1,  color: Color(0xffE5E5E5),  ),  ),  enabledBorder: OutlineInputBorder(  borderRadius: BorderRadius.all(Radius.circular(4)),  borderSide: BorderSide(  width: 1,  color: Color(0xffE5E5E5),  ),  ),  border: OutlineInputBorder(  borderRadius: BorderRadius.all(Radius.circular(4)),  borderSide: BorderSide(  width: 1,  ),  ),  errorBorder: OutlineInputBorder(  borderRadius: BorderRadius.all(Radius.circular(4)),  borderSide: BorderSide(  width: 1,  color: Colors.red,  )),  focusedErrorBorder: OutlineInputBorder(  borderRadius: BorderRadius.all(Radius.circular(4)),  borderSide: BorderSide(  width: 1,  color: Colors.red,  ),  ),  hintText: "Enter password" ?? "",  ),  ),  ],  ),  ),  SizedBox(  height: 15.0,  ),  OutlinedButton(  onPressed: () {  _validationKey.currentState.validate();  if (emailController.text.isEmpty) {  emailFocus.requestFocus();  } else if (pswdController.text.isEmpty ||  pswdController.text.length lt;= 8) {  pswdFocus.requestFocus();  }  },  child: Text("Validate"),  )  ],  ),  ),  );  } }