form_widget_issue.dart

import 'package:flutter/material.dart';

void main() {
  //final GlobalKey<FormState> _formState = GlobalKey();
  final GlobalKey<FormFieldState> _formFieldState = GlobalKey();

  runApp(MaterialApp(
    title: 'Flutter Demo',
    theme: ThemeData(
      visualDensity: VisualDensity.adaptivePlatformDensity,
    ),
    home: Scaffold(
      body: Center(
        child: Form(
          //key: _formState,
          autovalidateMode: AutovalidateMode.onUserInteraction,
          child: Column(
            children: [
              TextFormField(
                key: _formFieldState,
                validator: (value) {
                  return 'error1:$value';
                },
              ),
              TextFormField(
                validator: (value) {
                  return 'error2:$value';
                },
              ),
              TextFormField(
                validator: (value) {
                  return 'error3:$value';
                },
              ),
            ],
          ),
        ),
      ),
      floatingActionButton: FloatingActionButton(
        child: Icon(Icons.refresh),
        onPressed: () {
          _formFieldState.currentState.reset();
        },
      ),
    ),
  ));
}