How to Build a Sign In Screen in Flutter (Full Code + Preview)

import 'package:flutter/material.dart';

import 'widgets/cta_button.dart';
import 'widgets/sign_in_field.dart';

/// Sign In screen from the "bankee" UI kit.
///
/// A centered welcome header over a form board: Email (focused by default, per
/// the design) and Password fields, a right-aligned "Forgot Password?" link, a
/// primary CTA and a sign-up link.
///
/// Self-contained, pure Flutter. Bundles its exact design font (DM Sans) and
/// renders standalone when pushed as a route.
class SignInScreen extends StatefulWidget {
  const SignInScreen({super.key});

  @override
  State<SignInScreen> createState() => _SignInScreenState();
}

class _SignInScreenState extends State<SignInScreen> {
  static const Color _primary = Color(0xFF7165E3);
  static const Color _navy = Color(0xFF1C1939);
  static const Color _subtitle = Color(0xCC1C1939); // #1C1939 @ 80%

  final TextEditingController _email = TextEditingController();
  final TextEditingController _password = TextEditingController();

  @override
  void dispose() {
    _email.dispose();
    _password.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.white,
      // Tap anywhere to dismiss the keyboard (the Email field autofocuses).
      body: GestureDetector(
        onTap: () => FocusScope.of(context).unfocus(),
        child: SafeArea(
          child: SingleChildScrollView(
            padding: const EdgeInsets.fromLTRB(37, 66, 37, 32),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.stretch,
              children: <Widget>[
                const Text(
                  'Welcome Back!',
                  textAlign: TextAlign.center,
                  style: TextStyle(
                    fontFamily: 'DMSans',
                    fontSize: 35,
                    fontWeight: FontWeight.w700,
                    color: _navy,
                  ),
                ),
                const SizedBox(height: 21),
                const Text(
                  'Sign in to continue',
                  textAlign: TextAlign.center,
                  style: TextStyle(
                    fontFamily: 'DMSans',
                    fontSize: 15,
                    height: 25 / 15,
                    color: _subtitle,
                  ),
                ),
                const SizedBox(height: 87),
                SignInField(
                  hint: 'Email',
                  controller: _email,
                  autofocus: true,
                  keyboardType: TextInputType.emailAddress,
                  textInputAction: TextInputAction.next,
                ),
                const SizedBox(height: 5),
                SignInField(
                  hint: 'Password',
                  controller: _password,
                  isPassword: true,
                  textInputAction: TextInputAction.done,
                ),
                const SizedBox(height: 21),
                Align(
                  alignment: Alignment.centerRight,
                  child: GestureDetector(
                    behavior: HitTestBehavior.opaque,
                    onTap: () {},
                    child: const Text(
                      'Forgot Password?',
                      style: TextStyle(
                        fontFamily: 'DMSans',
                        fontSize: 12,
                        color: _subtitle,
                      ),
                    ),
                  ),
                ),
                const SizedBox(height: 35),
                CtaButton(
                  label: 'Sign in My Account',
                  color: _primary,
                  onPressed: () {},
                ),
                const SizedBox(height: 19),
                _SignUpLink(onTap: () {}),
              ],
            ),
          ),
        ),
      ),
    );
  }
}

/// "Don't have an account? - Sign Up" — regular text with a bold link.
class _SignUpLink extends StatelessWidget {
  const _SignUpLink({required this.onTap});

  final VoidCallback onTap;

  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      behavior: HitTestBehavior.opaque,
      onTap: onTap,
      child: Text.rich(
        const TextSpan(
          text: 'Don’t have an account? - ',
          style: TextStyle(
            fontFamily: 'DMSans',
            fontSize: 15,
            height: 25 / 15,
            fontWeight: FontWeight.w400,
            color: _SignInScreenState._subtitle,
          ),
          children: <InlineSpan>[
            TextSpan(
              text: 'Sign Up',
              style: TextStyle(fontWeight: FontWeight.w700),
            ),
          ],
        ),
        textAlign: TextAlign.center,
      ),
    );
  }
}