màn app có gạch chéo và load mãi không ngừng cũng không chuyển màn do đâu?

đăng nhập từ màn log in sang homescreen: màn cứ loanding mãi như này và có dấu gạch chéo đây là homescreen:

import 'package:flutter/cupertino.dart';

// import 'package:http/http.dart';
import 'package:flutter/material.dart';
import 'package:flutter_auth/Screens/Welcome/components/login_signup_btn.dart';



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

  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(backgroundColor: Colors.pink, title: Text('Home')),
      body: Column(
        children: [
          Row(children: [
            ElevatedButton(
                child: Text('log out'),
                style: ButtonStyle(
                    backgroundColor: MaterialStateProperty.all(Colors.red)),
                onPressed: () {Navigator.push(
                    context,
                    MaterialPageRoute(
                        builder: (context) => const LoginAndSignupBtn()
                    )
                );},

            ),

            ElevatedButton(
              child: Text('help'),
              style: ButtonStyle(
                  backgroundColor: MaterialStateProperty.all(Colors.white)),
              onPressed: () {},
            ),
            Center(
              child: Text('welcome'),
            ),
          ])
        ],
      ),
    );
  }

  @override
  State<homescreen> createState() => _homescreenState();
}

class _homescreenState extends State<homescreen> {
  @override
  Widget build(BuildContext context) {
    return const Placeholder();
  }
}

đây là màn login:

import 'package:flutter/material.dart';
import 'package:flutter_auth/Screens/HomeScreen/Home_screen.dart';
// import 'package:http/http.dart';
import '../../../components/already_have_an_account_acheck.dart';
import '../../../constants.dart';
import '../../Signup/signup_screen.dart';

class LoginForm extends StatelessWidget {
  const LoginForm({
    Key? key,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Form(
      child: Column(
        children: [
          TextFormField(
            keyboardType: TextInputType.emailAddress,
            textInputAction: TextInputAction.next,
            cursorColor: kPrimaryColor,
            onSaved: (email) {},
            decoration: InputDecoration(
              hintText: "Your email",
              prefixIcon: Padding(
                padding: const EdgeInsets.all(defaultPadding),
                child: Icon(Icons.person),
              ),
            ),
          ),
          Padding(
            padding: const EdgeInsets.symmetric(vertical: defaultPadding),
            child: TextFormField(
              textInputAction: TextInputAction.done,
              obscureText: true,
              cursorColor: kPrimaryColor,
              decoration: InputDecoration(
                hintText: "Your password",
                prefixIcon: Padding(
                  padding: const EdgeInsets.all(defaultPadding),
                  child: Icon(Icons.lock),
                ),
              ),
            ),
          ),

          const SizedBox(height: defaultPadding),
          Hero(
            tag: "login_btn",
            child: ElevatedButton(
                child: Text(
              "Login".toUpperCase(),
            ),
                onPressed: () {
                  Navigator.push(
                  context,
                  MaterialPageRoute(
                    builder: (context) => const homescreen()
                  ),
                );},
              //---------------------//

            ),
          ),
          const SizedBox(height: defaultPadding),
          AlreadyHaveAnAccountCheck(//gọi hàm
            press: () {
              Text('đã có một account ?');//press
              Navigator.push(   //push
                context,
                MaterialPageRoute(//hsfm sẵn
                  builder: (context) {
                    return SignUpScreen();//
                  },
                ),
              );
            },
          ),
        ],
      ),
    );
  }
}