Lang Q Localization

A Flutter localization package that seamlessly integrates with Lang Q to manage your app's translations with type-safe key generation.

Features

  • 🚀 Quick Setup - Get started in just 4 simple steps
  • 🔄 Automatic Sync - Pull translations directly from Lang Q without manual downloads
  • 🛡️ Type-Safe Keys - Auto-generated keys with required parameters prevent runtime errors
  • 🔢 Advanced Pluralization - Full support for plurals, including nested plural forms
  • 📦 Zero Boilerplate - Minimal configuration required

Installation

Add langq_localization to your pubspec.yaml:

dependencies:
  langq_localization: ^<version>

Then run:

flutter pub get

Setup Guide (Just 4 Steps)

Step 1: Configure API Key

Create a .env file in your project root and add your Lang Q project API key:

LANGQ_API_KEY=your_project_api_key_here

Note: Add .env to your .gitignore to keep your API key secure.

Step 2: Pull Translations

Run the following command to download your localization files and generate type-safe keys:

dart run langq_localization:pull

This generates keys as functions with required parameters:

// Generated from: "Hello, {userName}!"
static String welcomeMessage({required String userName}) {
  return LangQ.text('welcome.message', args: {'userName': userName});
}

Alternative: String Keys

If you prefer simple string getters without parameters:

dart run langq_localization:pull --strings

This generates:

// Generated from: "Hello, {userName}!"
static String get welcomeMessage => 'welcome.message';

Project Structure

After running dart run langq_localization:pull, your project will have:

lib/
├── l10n/
│   └── generated/
│       ├── langq_key.g.dart         # Translation keys
│       ├── langq_locales.g.dart     # Supported locales
│   └── translations/            # JSON translation files
│       ├── en-US.json
│       ├── fr-CA.json
│       └── ...

Add translations to assets

Add the translations folder to your pubspec.yaml:

flutter:
  assets:
    - lib/l10n/translations/

Step 3: Initialize Lang Q

Update your main.dart:

import 'package:<your_package_name>/l10n/generated/langq_locales.g.dart';
import 'package:flutter/material.dart';
import 'package:langq_localization/langq.dart';

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  
  // Initialize Lang Q
  await LangQ.init();
  
  runApp(const MyApp());
}

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

  @override
  Widget build(BuildContext context) {
    // Wrap MaterialApp with LangQ.builder
    return LangQ.builder(
      builder: (context, langq) {
        return MaterialApp(
          // Required delegates for localization
          localizationsDelegates: langq.localizationsDelegates,
          
          // Current locale
          locale: langq.currentLocale,
          
          // Auto-generated supported locales
          supportedLocales: LangQLocales.supportedLocales,
          
          title: 'Your App',
          home: const HomePage(),
        );
      },
    );
  }
}

Step 4: Using Translations

import 'package:<your_package_name>/l10n/generated/langq_key.g.dart';

class HomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Center(
        child: Text(
          // Type-safe with required parameters
          LangQKey.welcomeMessage(userName: 'John'),
          style: Theme.of(context).textTheme.headlineMedium,
        ),
      ),
    );
  }
}

Method 2: Extension Method

For a more familiar syntax similar to easy_localization:

import 'package:<your_package_name>/l10n/generated/langq_key.g.dart';

Text(
  LangQKey.welcomeMessage.tr(args: {'userName': 'John'}),
  style: Theme.of(context).textTheme.bodyLarge,
)

Note: To use the .tr() extension method, generate string keys by running:

dart run langq_localization:pull --strings

Built-in Formatting

Lang Q provides built-in formatting extensions powered by intl for common data types. All formatters automatically use the current locale.

Number Formatting

Text(
  1234567.numberFormat(),  // Output: 1,234,567 (en) or 1 234 567 (fr)
  style: Theme.of(context).textTheme.bodyLarge,
),

Date Formatting

Text(
  DateTime.now().dateFormat(),  // Output: Jan 15, 2025 (en) or 15 janv. 2025 (fr)
  style: Theme.of(context).textTheme.bodyLarge,
),

Time Formatting

Text(
  DateTime.now().timeFormat(),  // Output: 3:45 PM (en) or 15:45 (fr)
  style: Theme.of(context).textTheme.bodyLarge,
),

Percentage Formatting

Text(
  0.854.percentageFormat(),  // Output: 85.4%
  style: Theme.of(context).textTheme.bodyLarge,
),

Currency Formatting

Note: Currency symbols vary by locale. Consider exchange rates for multi-currency apps.

Text(
  1234.56.currencyFormat(),  // Output: $1,234.56 (en-US) or 1 234,56 € (fr-FR)
  style: Theme.of(context).textTheme.bodyLarge,
),

Custom Formatting

You can also use intl directly for advanced formatting needs:

import 'package:intl/intl.dart';

// Custom date pattern
final customDate = DateFormat('EEEE, MMMM d, y').format(DateTime.now());

Changing Locale

Using Generated Locale Constants

// Type-safe locale switching
await LangQ.setLocale(LangQLocales.frCA);

Using Locale Object

await LangQ.setLocale(const Locale('fr', 'CA'));

Getting Current Locale

final currentLocale = LangQ.currentLocale;
print('Current language: ${currentLocale.languageCode}');

Best Practices

  1. Keep your .env file secure - Never commit API keys to version control
  2. Use function keys - They provide compile-time safety for parameters
  3. Organize keys hierarchically - Use dot notation for better organization (e.g., auth.login.button)

Troubleshooting

Missing Translations

If a translation is missing, Lang Q will display the key itself as a fallback.

Support

📧 Email: team@lang-q.com

License

This package is licensed under the MIT License. See LICENSE for details.

Libraries

langq