Dependencies

Overview

Vitu uses carefully selected Flutter packages to provide wellness tracking features including AI-powered nutrition analysis, activity tracking, data visualization, and local storage.

SDK Requirements

Dart SDK

environment:
  sdk: ^3.10.8

Purpose: Minimum Dart SDK version required for language features and compatibility. Why This Version:

Dart 3.10.8 provides null safety, enhanced type checking, and modern language features
Required for compatibility with Flutter 3.x and Material 3 components

Production Dependencies

Core Flutter

flutter

flutter:
  sdk: flutter

Purpose: Core Flutter framework for building cross-platform UIs. Usage in Vitu:

Material Design widgets (Scaffold, AppBar, BottomNavigationBar)
State management (StatefulWidget, StatelessWidget)
Navigation (Navigator, MaterialPageRoute)
Animations (AnimationController, AnimatedSwitcher)

cupertino_icons

cupertino_icons: ^1.0.8

Purpose: iOS-style icons for Cupertino design language. Version: 1.0.8 (latest stable) Usage in Vitu:

Provides iOS-style icons for cross-platform consistency
Used in navigation and UI elements

Media & File Management

image_picker

image_picker: ^1.1.2

Purpose: Allows users to select images from camera or gallery. Version: 1.1.2 Usage in Vitu:

Capturing food photos for AI analysis (lib/main.dart:534-569)
Gallery selection for analyzing saved photos
Both camera and gallery sources supported

Platform Requirements:

iOS: Requires NSCameraUsageDescription and NSPhotoLibraryUsageDescription in Info.plist
Android: Requires camera and storage permissions in AndroidManifest.xml

Code Example:

final ImagePicker picker = ImagePicker();
final XFile? xfile = await picker.pickImage(
  source: ImageSource.camera,
  imageQuality: 85,
);

path_provider

path_provider: ^2.1.4

Purpose: Provides platform-specific file system paths. Version: 2.1.4 Usage in Vitu:

Storing captured food photos (lib/main.dart:550-554)
Accessing app documents directory
Persistent local file storage

Code Example:

final dir = await getApplicationDocumentsDirectory();
final path = '${dir.path}/vitu_food_$timestamp.jpg';

Data Visualization

fl_chart

fl_chart: ^0.68.0

Purpose: Beautiful, animated charts for data visualization. Version: 0.68.0 Usage in Vitu:

PieChart: Nutritional macros breakdown (protein/carbs/fat) - lib/main.dart:1060-1070
LineChart: Real-time exercise activity monitoring - lib/main.dart:2242-2308
BarChart: Weekly step count and hydration trends - lib/main.dart:2344-2430

Chart Types Used:

PieChart - Nutrient distribution
LineChart - Cardio activity over time
BarChart - Weekly activity summaries

Features:

Smooth animations (swapAnimationDuration)
Custom colors and gradients
Touch interactions
Responsive sizing

Local Storage

shared_preferences

shared_preferences: ^2.2.3

Purpose: Simple key-value storage for app preferences. Version: 2.2.3 Usage in Vitu:

Lightweight preference storage
Compatibility layer (primary storage is Hive)

hive

hive: ^2.2.3

Purpose: Fast, lightweight NoSQL database for Flutter. Version: 2.2.3 Usage in Vitu:

Core data storage engine
Stores user profiles, settings, and activity data
No backend required - 100% local

Boxes Used:

users - User profiles and authentication
user_settings - Theme and preferences
daily_exercise - Step counts and activities
hydration_logs - Water intake events
daily_hydration_summary - Daily summaries

Why Hive?

Fast read/write performance
No SQL schema required
Type-safe with code generation
Cross-platform support
Offline-first architecture

hive_flutter

hive_flutter: ^1.1.0

Purpose: Flutter-specific Hive extensions and initialization. Version: 1.1.0 Usage in Vitu:

Hive initialization (lib/main.dart:23-28)
Flutter-optimized storage paths
Box management helpers

Initialization:

await Hive.initFlutter();
await Hive.openBox('users');
await Hive.openBox('user_settings');
await Hive.openBox('daily_exercise');
await Hive.openBox('hydration_logs');
await Hive.openBox('daily_hydration_summary');

Activity & Sensors

geolocator

geolocator: ^12.0.0

Purpose: Location tracking for activity detection and speed calculation. Version: 12.0.0 Usage in Vitu:

Detecting movement speed (km/h) - lib/main.dart:1773-1791
Preventing step counting while in vehicle (speed > 15 km/h)
Activity classification (walking, running, vehicle)
Location permissions management

Permission Handling:

bool enabled = await Geolocator.isLocationServiceEnabled();
LocationPermission perm = await Geolocator.checkPermission();
if (perm == LocationPermission.denied) {
  perm = await Geolocator.requestPermission();
}

Why This Package?

Accurate GPS positioning
Continuous position stream
Built-in permission handling
Cross-platform support

sensors_plus

sensors_plus: ^5.0.0

Purpose: Access to device sensors (accelerometer, gyroscope). Version: 5.0.0 Usage in Vitu:

Step detection via accelerometer - lib/main.dart:1806-1848
Movement magnitude calculation
Real-time activity monitoring

Implementation:

_accelSub = userAccelerometerEventStream().listen((e) {
  final mag = math.sqrt(e.x * e.x + e.y * e.y + e.z * e.z);
  if (mag > threshold) {
    // Step detected
  }
});

Detection Thresholds:

Walking: magnitude > 0.9
Running: magnitude > 1.4
Debounce: 320-450ms between steps

Note: Replaced activity_recognition_flutter due to AGP 8+ incompatibility (see pubspec.yaml:24).

AI Integration

google_generative_ai

google_generative_ai: ^0.4.0

Purpose: Google Gemini AI for image analysis and content generation. Version: 0.4.0 (downgraded from 0.5.0 for stability) Usage in Vitu:

Food Analysis - Analyzes photos to extract:
- Dish name
- Estimated calories (kcal)
- Macronutrients (protein, carbs, fat)
- Personalized based on user profile (age, weight, height, gender)
Recipe Recommendations - Generates 3 healthy recipes:
- Ingredients list
- Preparation time
- Difficulty level
- Nutritional estimates
- Health benefits explanation
Workout Suggestions - Creates exercise routines:
- Personalized to user fitness level
- 4 sessions per routine type (Strength/Yoga/Stretching)
- Detailed exercise breakdowns

Model Used: gemini-2.5-flash API Key Configuration:

const apiKey = 'AIzaSyCEwgwToG9cfPvf2wzNHGOhSeXCLafD1ms';
_geminiModel = GenerativeModel(
  model: 'gemini-2.5-flash',
  apiKey: apiKey,
);

Security Warning:

API key is hardcoded in source (lib/main.dart:489)
Should use environment variables or secure storage in production
Generate new key at: https://aistudio.google.com/app/apikey

Personalization:

String buildUserPromptPersonalization() {
  final u = getCurrentUser();
  return 'User data: age ${u.edad}, weight ${u.peso} kg, height ${u.altura} cm, gender ${u.genero}. Personalize recommendations.';
}

Error Handling:

GenerativeAIException - API errors (invalid key, rate limits)
SocketException - Network connectivity issues
TimeoutException - 20-second timeout on requests

Monitoring

screen_state

screen_state: 5.0.0

Purpose: Detect screen on/off events for sleep tracking. Version: 5.0.0 (exact version, no caret) Usage in Vitu:

Automatic sleep detection when screen turns off (19:00-07:00)
Sleep duration calculation
Automatic quality rating based on hours slept

Note: Current implementation uses WidgetsBindingObserver for app lifecycle (paused/resumed) rather than direct screen_state integration.

Development Dependencies

flutter_test

dev_dependencies:
  flutter_test:
    sdk: flutter

Purpose: Unit and widget testing framework. Usage: Testing infrastructure (not currently implemented).

flutter_lints

flutter_lints: ^6.0.0

Purpose: Recommended linting rules for Flutter projects. Version: 6.0.0 Configuration: Defined in analysis_options.yaml. Benefits:

Code quality enforcement
Best practices recommendations
Catch common mistakes
Consistent code style

flutter_launcher_icons

flutter_launcher_icons: ^0.14.4

Purpose: Automatically generates app launcher icons for all platforms. Version: 0.14.4 Configuration:

flutter_launcher_icons:
  android: true
  ios: true
  image_path: "assets/WhatsApp Image 2026-02-16 at 12.16.07 PM.jpeg"
  remove_alpha_ios: true

Usage: Run flutter pub run flutter_launcher_icons after configuration. Platforms Supported:

Android (adaptive icons)
iOS (app icon set)
Automatically handles all required sizes

Dependency Version Constraints

Constraint Types

Constraint	Example	Meaning
Caret (^)	`^1.0.8`	Compatible with 1.x.x (1.0.8 ≤ version < 2.0.0)
Exact	`5.0.0`	Exact version only
Range	`>=1.0.0 <2.0.0`	Specified range

Version Strategy

Core packages (flutter, sensors_plus, geolocator): Use caret (^) for flexibility
Critical packages (screen_state): Use exact version for stability
AI packages (google_generative_ai): Pinned to 0.4.0 (downgraded from 0.5.0)

Removed Dependencies

activity_recognition_flutter

# Removed due to AGP 8+ incompatibility
# activity_recognition_flutter: ^4.2.0

Reason: Incompatible with Android Gradle Plugin 8+ Replacement: Combination of geolocator + sensors_plus for activity detection Migration Notes:

Manual activity classification using speed and accelerometer data
Custom thresholds for walking/running/vehicle detection
See lib/main.dart:1633 for ActivityKind enum

Assets Configuration

flutter:
  uses-material-design: true
  assets:
    - assets/WhatsApp Image 2026-02-16 at 12.16.07 PM.jpeg

Purpose:

Material Design icon set
App launcher icon source image

Installation

Get All Dependencies

flutter pub get

Update Dependencies

flutter pub upgrade

Check Outdated

flutter pub outdated

Platform-Specific Setup

Android Permissions

Add to android/app/src/main/AndroidManifest.xml:

<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />

iOS Permissions

Add to ios/Runner/Info.plist:

<key>NSCameraUsageDescription</key>
<string>Take photos of food for nutritional analysis</string>
<key>NSPhotoLibraryUsageDescription</key>
<string>Select photos from gallery for analysis</string>
<key>NSLocationWhenInUseUsageDescription</key>
<string>Track activity and calculate walking/running speed</string>

Troubleshooting

Build Errors

If you encounter build issues:

Clean build cache:
```
flutter clean
flutter pub get
```
Check Flutter/Dart versions:
```
flutter --version
dart --version
```
Update Flutter:
```
flutter upgrade
```

Gemini API Issues

Verify API key is valid
Check internet connectivity
Monitor rate limits (free tier: 60 requests/minute)
Generate new key at: https://aistudio.google.com/app/apikey

Hive Migration

If data schema changes:

// Delete box to reset data
await Hive.deleteBoxFromDisk('box_name');
await Hive.openBox('box_name');

Resources

Best Practices

​Overview

​SDK Requirements

​Dart SDK

​Production Dependencies

​Core Flutter

​flutter

​cupertino_icons

​Media & File Management

​image_picker

​path_provider

​Data Visualization

​fl_chart

​Local Storage

​shared_preferences

​hive

​hive_flutter

​Activity & Sensors

​geolocator

​sensors_plus

​AI Integration

​google_generative_ai

​Monitoring

​screen_state

​Development Dependencies

​flutter_test

​flutter_lints

​flutter_launcher_icons

​Dependency Version Constraints

​Constraint Types

​Version Strategy

​Removed Dependencies

​activity_recognition_flutter

​Assets Configuration

​Installation

​Get All Dependencies

​Update Dependencies

​Check Outdated

​Platform-Specific Setup

​Android Permissions

​iOS Permissions

​Troubleshooting

​Build Errors

​Gemini API Issues

​Hive Migration

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