retry-until-internet

This skill combines checkInternet with retry.unlimited for persistent loading of critical data.

What This Skill Does

Creates a pattern that:

• Checks for internet connectivity
• Retries indefinitely until connection is restored
• Automatically loads data when internet returns

Use Case

Perfect for:

• Critical app startup data
• Configuration that must be loaded
• Data that the app cannot function without

Instructions

Step 1: Combine checkInternet and retry.unlimited

import 'package:bloc_superpowers/bloc_superpowers.dart';

class AppCubit extends Cubit<AppState> {
  AppCubit() : super(const AppState());

  void loadInitialData() => mix(
    key: this,
    checkInternet: checkInternet,
    retry: retry.unlimited,
    () async {
      final config = await api.getAppConfig();
      final user = await api.getCurrentUser();
      emit(state.copyWith(config: config, user: user));
    },
  );
}

Step 2: Configure Retry Delay (Optional)

Control how frequently it rechecks:

void loadInitialData() => mix(
  key: this,
  checkInternet: checkInternet(maxRetryDelay: 1.sec),
  retry: retry.unlimited(maxDelay: 5.sec),
  () async {
    final config = await api.getAppConfig();
    emit(state.copyWith(config: config));
  },
);

How It Works

App starts
    ↓
Check internet → No internet
    ↓
Wait 1 second, retry
    ↓
Check internet → No internet
    ↓
Wait 2 seconds, retry (exponential backoff)
    ↓
Check internet → No internet
    ↓
Wait 4 seconds, retry
    ↓
... keeps trying ...
    ↓
Check internet → Has internet!
    ↓
Execute API call
    ↓
Success! Data loaded

Configuration Options

Fast Retry

For critical data that needs to load ASAP:

void loadCriticalData() => mix(
  key: this,
  checkInternet: checkInternet(maxRetryDelay: 500.millis),
  retry: retry.unlimited(
    initialDelay: 500.millis,
    maxDelay: 2.sec,
  ),
  () async {
    final data = await api.getCriticalData();
    emit(data);
  },
);

Slow Retry

For less critical data:

void loadOptionalData() => mix(
  key: this,
  checkInternet: checkInternet(maxRetryDelay: 5.sec),
  retry: retry.unlimited(
    initialDelay: 2.sec,
    maxDelay: 30.sec,
  ),
  () async {
    final data = await api.getOptionalData();
    emit(state.copyWith(optionalData: data));
  },
);

Widget Integration

Show loading state while waiting for internet:

class SplashScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    if (context.isWaiting(AppCubit)) {
      return const Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            CircularProgressIndicator(),
            SizedBox(height: 16),
            Text('Waiting for connection...'),
          ],
        ),
      );
    }

    if (context.isFailed(AppCubit)) {
      // This shouldn't happen with unlimited retry,
      // but handle just in case
      return const Center(child: Text('Error loading'));
    }

    // Data loaded, navigate away
    return const HomeScreen();
  }
}

Complete Example

// Cubit
class AppCubit extends Cubit<AppState> {
  AppCubit() : super(const AppState());

  void init() => mix(
    key: this,
    checkInternet: checkInternet(maxRetryDelay: 1.sec),
    retry: retry.unlimited(maxDelay: 10.sec),
    () async {
      // Load all critical startup data
      final config = await api.getConfig();
      final user = await api.getCurrentUser();
      final features = await api.getFeatureFlags();

      emit(state.copyWith(
        config: config,
        user: user,
        features: features,
        isInitialized: true,
      ));
    },
  );
}

// Main
void main() {
  runApp(
    Superpowers(
      child: BlocProvider(
        create: (_) => AppCubit()..init(),  // Start loading immediately
        child: const MyApp(),
      ),
    ),
  );
}

// Splash Screen
class SplashScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final state = context.watch<AppCubit>().state;

    if (state.isInitialized) {
      // Navigate to home when loaded
      WidgetsBinding.instance.addPostFrameCallback((_) {
        Navigator.pushReplacementNamed(context, '/home');
      });
    }

    return Scaffold(
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            const FlutterLogo(size: 100),
            const SizedBox(height: 32),
            if (context.isWaiting(AppCubit)) ...[
              const CircularProgressIndicator(),
              const SizedBox(height: 16),
              const Text('Loading...'),
            ],
          ],
        ),
      ),
    );
  }
}

Reusable Config/Preset

Create a reusable configuration:

// Config
const criticalLoadConfig = MixConfig(
  checkInternet: checkInternet(maxRetryDelay: 1.sec),
  retry: retry.unlimited(maxDelay: 10.sec),
);

// Usage
void loadData() => mix(
  key: this,
  config: criticalLoadConfig,
  () async { ... },
);

// Or as a preset
const criticalLoad = MixPreset(
  checkInternet: checkInternet(maxRetryDelay: 1.sec),
  retry: retry.unlimited(maxDelay: 10.sec),
);

// Usage
void loadData() => criticalLoad(
  key: this,
  () async { ... },
);

Key Points

1. Use for critical data that the app cannot function without
2. Configure delays based on urgency
3. Show user feedback ("Waiting for connection...")
4. Create reusable configs for consistent behavior