Every time I focus on TextField or TextFormField the screen reload and then the App freeze

Question

This is my code, every time I click on TexFormField, giving focus to it, the page reload with this error in debug:

I/AssistStructure(16650): Flattened final assist data: 484 bytes, containing 1 windows, 3 views.

Then the App froze. I cannot be very sure but it seems happening since the last upgrade to the Flutter version. Looking on the Net this can be related to a rebuild, but this seems not the case.

Could someone help ?

class Profile extends StatefulWidget {
  const Profile({Key? key}) : super(key: key);

  @override
  State createState() {
    return ProfileState();
  }
}

class ProfileState extends State<Profile> {
  final _formKey = GlobalKey<FormState>();

  @override
  Widget build(BuildContext context) {
    return
        Form(
          key: _formKey,
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: <Widget>[
              TextFormField(
                validator: (value) {
                  if (value == null || value.isEmpty) {
                    return 'Please enter some text';
                  }
                  return null;
                },
              ),
            ],
          )
        );
   }
}

Answer 1

I tried to run your code on an Android emulator. However, I couldn't reproduce the error. TextFormField was focused without lags. P.S. I'm using master channel (2.13.0-0.0.pre.1002)

import 'package:flutter/material.dart';
void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
       home: ProfileScreen()
    );
  }
}
class ProfileScreen extends StatelessWidget {
  const ProfileScreen({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: const Text('Profile'),
          centerTitle: true,
        ),
        body:const Profile()
    );
  }
}
class Profile extends StatefulWidget {
  const Profile({Key? key}) : super(key: key);

  @override
  State createState() {
    return ProfileState();
  }
}

class ProfileState extends State<Profile> {
  final _formKey = GlobalKey<FormState>();

  @override
  Widget build(BuildContext context) {
    return
      Form(
          key: _formKey,
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: <Widget>[
              TextFormField(
                validator: (value) {
                  if (value == null || value.isEmpty) {
                    return 'Please enter some text';
                  }
                  return null;
                },
              ),
            ],
          )
      );
  }
}