flutter_alone #

A robust Flutter plugin for preventing duplicate execution of desktop applications, offering advanced process management and cross-user detection.

Features #

• Duplicate Execution Prevention

  • System-wide mutex management
  • Cross-user account detection
  • Process-level duplicate checking

• Window Management

  • Automatic window focusing
  • Window restoration handling
  • Bring to front functionality
  • Enhanced taskbar identification
  • Rich MessageBox with application icon

• Customizable Messaging

  • Multi-language support (English/Korean)
  • Custom message templates
  • Configurable message box display
  • UTF-8 text encoding support

• Process Management

  • Detailed process information tracking
  • Safe resource cleanup
  • Robust error handling

Platform Support #

Getting Started #

Add flutter_alone to your pubspec.yaml:

dependencies:
  flutter_alone: ^2.0.1

Usage #

Import the package:

import 'package:flutter_alone/flutter_alone.dart';

Basic Usage with Default Settings #

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  
  if (!await FlutterAlone.instance.checkAndRun()) {  // Uses EnMessageConfig by default
    exit(0);
  }
  
  runApp(const MyApp());
}

Using Korean Messages #

if (!await FlutterAlone.instance.checkAndRun(
  messageConfig: const KoMessageConfig(),
)) {
  exit(0);
}

Custom Message Configuration #

final messageConfig = CustomMessageConfig(
  customTitle: 'Application Notice',
  customMessage: 'Application is already running',
  showMessageBox: true,  // Optional, defaults to true
);

if (!await FlutterAlone.instance.checkAndRun(messageConfig: messageConfig)) {
  exit(0);
}

Resource Cleanup #

Always remember to dispose of resources when your application closes:

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

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  @override
  void dispose() {
    FlutterAlone.instance.dispose();
    super.dispose();
  }

  // ... rest of your widget implementation
}

Advanced Features #

Message Configuration Classes #

The plugin provides three types of message configurations:

• EnMessageConfig: Default English messages
• KoMessageConfig: Korean messages
• CustomMessageConfig: Custom messages with template support

Windows Implementation Details #

• Uses Windows Named Mutex for system-wide instance detection
• Implements robust cross-user detection through global mutex naming
• Ensures proper cleanup of system resources
• Full Unicode support for international character sets
• Advanced window management capabilities
• Enhanced taskbar and message box icon handling

Error Handling #

The plugin provides detailed error information through the AloneException class:

try {
  await FlutterAlone.instance.checkAndRun();
} on AloneException catch (e) {
  print('Error Code: ${e.code}');
  print('Message: ${e.message}');
  print('Details: ${e.details}');
}

Contributing #

Contributions are welcome! Please read our contributing guidelines before submitting pull requests.