Form validator is not showing error in flutter why?-CodePudding

I created form when i click on button to validate validator not showing error.

  GlobalKey<FormState> formkey= GlobalKey<FormState>();

Created Global Key in my code

Form(
              key: formkey,
              child: ListView(
                scrollDirection: Axis.vertical,
                children: [
                  Padding(
                    padding: const EdgeInsets.all(20),
                    child: TextFormField(
                      controller: _name,
                      validator: (value) {
                        if (value == null || value == value.isEmpty) {
                          return "Enter Name";
                        }
                          return null;
                      },
                      decoration: InputDecoration(
                          enabledBorder: OutlineInputBorder(),
                          focusedBorder: OutlineInputBorder(),
                          labelText: "Name",
                          prefixIcon: Icon(Icons.person),
                          errorStyle: TextStyle(color: Colors.red)),
                    ),
                  ),

I created form

Center(
                          child: ElevatedButton(
                              onPressed: () {
                                if (formkey.currentState!.validate()) {
                                  setState(() {
                                    name = _name.text;
                                    email = _email.text;
                                    password = _password.text;
                                  });
                                  addUser();
                                  clear();
                                }
                              },
                              child: Text("Register"))),

Code of button This is the code help me.

CodePudding user response：

remove value == from the condition it will work. write like this

if (value == null || value.isEmpty)

CodePudding user response：

I solved your answer like this:

import 'package:flutter/material.dart';

class MyStackAns extends StatefulWidget {
const MyStackAns({super.key});

@override
State<MyStackAns> createState() => _MyStackAnsState();
}

class _MyStackAnsState extends State<MyStackAns> {
 GlobalKey<FormState> formkey = GlobalKey<FormState>();
 final TextEditingController _name = TextEditingController();

 @override
 Widget build(BuildContext context) {
  return Scaffold(
  appBar: AppBar(
    title: const Text('Stack Answers'),
  ),
  body: Column(
    children: [
      Form(
        key: formkey,
        autovalidateMode: AutovalidateMode.onUserInteraction,
        child: Padding(
          padding: const EdgeInsets.all(20),
          child: TextFormField(
            controller: _name,
            validator: (value) {
              if (value == null || value.isEmpty) {
                return "Enter Name";
              }
              return null;
            },
            decoration: const InputDecoration(
                enabledBorder: OutlineInputBorder(), focusedBorder: OutlineInputBorder(), labelText: "Name", prefixIcon: Icon(Icons.person), errorStyle: TextStyle(color: Colors.red)),
          ),
        ),
      ),
      Center(
          child: ElevatedButton(
              onPressed: () {
                if (formkey.currentState!.validate()) {
                  //Perform your validate task here

                }
              },
              child: const Text("Register"))),
    ],
  ),
);
  }
   }