noise/lib/login/loginscreen.dart

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

// ToDo: remove when done: currently only for testing purposes

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      title: 'Noise!',
      home: LoginPage(),
    );
  }
}

class LoginPage extends StatefulWidget {
  @override
  _LoginPageState createState() => _LoginPageState();
}

class _LoginPageState extends State<LoginPage> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Welcome')),
      // https://www.kindacode.com/article/flutter-show-hide-password-in-textfield-textformfield/
      // https://www.kindacode.com/article/flutter-filteringtextinputformatter/
      body: Center(
        child: new ListView(
          shrinkWrap: true,
          padding: const EdgeInsets.all(20.0),
          children: [
            new UsernameField(),
            new PasswordField(),
          ],
        ),
      ),
    );
  }
}

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

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.all(10),
      child: Center(
        child: TextField(
            decoration: InputDecoration(
          hintText: 'Username',
          border: OutlineInputBorder(borderRadius: BorderRadius.circular(10)),
        )),
      ),
    );
  }
}

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

  @override
  _PasswordFieldState createState() => _PasswordFieldState();
}

class _PasswordFieldState extends State<PasswordField> {
  bool _isPasswordObscure = true;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.all(10),
      child: Center(
        child: TextField(
            obscureText: _isPasswordObscure,
            decoration: InputDecoration(
                hintText: 'Password',
                border:
                    OutlineInputBorder(borderRadius: BorderRadius.circular(10)),
                suffixIcon: IconButton(
                  icon: Icon(_isPasswordObscure
                      ? Icons.visibility
                      : Icons.visibility_off),
                  onPressed: () {
                    setState(() {
                      _isPasswordObscure = !_isPasswordObscure;
                    });
                  },
                ))),
      ),
    );
  }
}