flutter_data_shp_provider

A singleton wrapper around SharedPreferences for managing authentication and session data with built-in error handling and debug logging.

Features

Singleton Pattern: Ensures a single instance manages all SharedPreferences operations throughout your app lifecycle
Error Handling: All read/write operations are wrapped in try-catch blocks with graceful fallbacks
Debug Logging: Built-in logging that only prints in debug mode (kDebugMode)
Type Safety: All operations use string-based storage with clear APIs
Async Initialization: Explicit initialization pattern prevents race conditions
Convenient APIs: Both generic (getValue/saveValue) and specific getters/setters for common auth/session data

Getting Started

Installation

Add this to your package's pubspec.yaml file:

dependencies:
  flutter_data_shp_provider: ^0.0.1

Then run:

flutter pub get

Basic Usage

1. Initialize the provider

Initialize the provider early in your app lifecycle, typically in main():

import 'package:flutter_data_shp_provider/flutter_data_shp_provider.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();

  // Initialize SharedPreferences
  await DataShpProvider().initPrefs();

  runApp(MyApp());
}

2. Check initialization status

if (DataShpProvider().isInitialized) {
  // Safe to use
}

3. Use generic methods

// Save a value
await DataShpProvider().saveValue('myKey', 'myValue');

// Read a value
String value = DataShpProvider().getValue('myKey');

// Read with default value
String value = DataShpProvider().getValue('myKey', defaultValue: 'default');

4. Use specific auth/session getters and setters

// Save authentication data
await DataShpProvider().setToken('abc123token');
await DataShpProvider().setIdSesion('session-id-123');
await DataShpProvider().setKeyLogin('user@example.com');

// Read authentication data
String token = DataShpProvider().token;
String sessionId = DataShpProvider().idSesion;
String userLogin = DataShpProvider().keyLogin;

API Reference

Initialization

Future<void> initPrefs() - Initialize SharedPreferences (call before any other operations)
bool get isInitialized - Check if the provider has been initialized

Generic Methods

String getValue(String key, {String defaultValue = ''}) - Read a value by key
Future<bool> saveValue(String key, String value) - Save a value by key

Authentication & Session Getters/Setters

Getter	Setter	Description
`keyLogin`	`setKeyLogin(String)`	User login/email
`passwordLogin`	`setPasswordLogin(String)`	User password
`idSesion`	`setIdSesion(String)`	Session identifier
`token`	`setToken(String)`	Authentication token
`validityInSeconds`	`setValidityInSeconds(String)`	Token validity duration
`idColeccionAuth`	`setIdColeccionAuth(String)`	Auth collection ID
`tipoUsuarioAuth`	`setTipoUsuarioAuth(String)`	User type for auth
`coleccionAuth`	`setColeccionAuth(String)`	Auth collection name
`idAppCliente`	`setIdAppCliente(String)`	Client app identifier
`offset`	`setOffset(String)`	Time offset for sync

Utility Methods

Future<bool> limpiarPreferencias() - Clear all preferences (use with caution)
static void logDebug(String message) - Log messages in debug mode only

Example

See the example directory for a complete sample application.

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

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await DataShpProvider().initPrefs();
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: Text('DataShpProvider Example')),
        body: Center(
          child: ElevatedButton(
            onPressed: () async {
              // Save user session
              await DataShpProvider().setToken('my-secure-token');
              await DataShpProvider().setIdSesion('session-123');

              // Read values
              print('Token: ${DataShpProvider().token}');
              print('Session: ${DataShpProvider().idSesion}');
            },
            child: Text('Save & Read Session'),
          ),
        ),
      ),
    );
  }
}

Error Handling

All operations gracefully handle errors:

Uninitialized state: Returns default values or false for write operations
Read errors: Returns the specified defaultValue (or empty string)
Write errors: Returns false
All errors are logged in debug mode for troubleshooting

Additional Information

Contributing

Contributions are welcome! Please feel free to submit issues or pull requests.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Support

For issues, questions, or feature requests, please file an issue on the project repository.