friendly_captcha_flutter 0.1.0

FriendlyCaptcha v2 widget for Flutter. Privacy-first, accessible bot protection for Android, iOS, and Web (Wasm-compatible).

example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:friendly_captcha_flutter/friendly_captcha_flutter.dart';

/// Replace with your own sitekey from https://app.friendlycaptcha.com/, or use
/// one of the documented test sitekeys at
/// https://developer.friendlycaptcha.com/docs/v2/guides/automated-testing.
const String kDemoSitekey = 'FCMGEMUD2KTDSQ5H';

void main() {
  runApp(const ExampleApp());
}

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'friendly_captcha_flutter example',
      theme: ThemeData(
        useMaterial3: true,
        colorSchemeSeed: Colors.indigo,
        brightness: Brightness.light,
      ),
      darkTheme: ThemeData(
        useMaterial3: true,
        colorSchemeSeed: Colors.indigo,
        brightness: Brightness.dark,
      ),
      home: const SignUpFormPage(),
    );
  }
}

class SignUpFormPage extends StatefulWidget {
  const SignUpFormPage({super.key});

  @override
  State<SignUpFormPage> createState() => _SignUpFormPageState();
}

class _SignUpFormPageState extends State<SignUpFormPage> {
  final _captcha = FriendlyCaptchaController();
  final _emailController = TextEditingController();

  @override
  void initState() {
    super.initState();
    _captcha.addListener(_onCaptchaChanged);
  }

  @override
  void dispose() {
    _captcha
      ..removeListener(_onCaptchaChanged)
      ..dispose();
    _emailController.dispose();
    super.dispose();
  }

  void _onCaptchaChanged() => setState(() {});

  void _submit() {
    final solution = _captcha.solution;
    if (solution == null) return;
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text(
          'Would POST to your backend with solution: '
          '${solution.substring(0, solution.length.clamp(0, 24))}…',
        ),
      ),
    );
    // After a real submit you'd reset on failure so the user gets a fresh
    // challenge. Doing it unconditionally here keeps the demo simple.
    _captcha.reset();
  }

  @override
  Widget build(BuildContext context) {
    final stateLabel = _captcha.lastResult?.state.name ?? 'idle';
    return Scaffold(
      appBar: AppBar(title: const Text('FriendlyCaptcha demo')),
      body: Center(
        child: ConstrainedBox(
          constraints: const BoxConstraints(maxWidth: 420),
          child: Padding(
            padding: const EdgeInsets.all(24),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.stretch,
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                TextField(
                  controller: _emailController,
                  keyboardType: TextInputType.emailAddress,
                  decoration: const InputDecoration(
                    labelText: 'Email',
                    border: OutlineInputBorder(),
                  ),
                ),
                const SizedBox(height: 16),
                FriendlyCaptcha(
                  sitekey: kDemoSitekey,
                  controller: _captcha,
                  onResult: (result) {
                    if (result.isError) {
                      debugPrint('Captcha error: ${result.error}');
                    }
                  },
                ),
                const SizedBox(height: 16),
                FilledButton(
                  onPressed: _captcha.hasSolution ? _submit : null,
                  child: const Text('Sign up'),
                ),
                const SizedBox(height: 8),
                Text(
                  'Captcha state: $stateLabel',
                  textAlign: TextAlign.center,
                  style: Theme.of(context).textTheme.bodySmall,
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}