🏃‍♂️🏊‍♀️🚴‍♂️ Fitness Tracker App (Flutter)

A multi-sport fitness tracking app built with Flutter that allows users to log workouts, track progress over time, and unlock achievement badges — all offline-first using local storage.

The app currently supports:

• 🏊 Swimming
• 🏃 Running
• 🚴 Biking

Each sport has its own tailored input flow, statistics, and badge evaluation while sharing a common data and UI structure.

✨ Key Features

📝 Activity Logging

• Log workouts with sport-specific inputs:
  • Swimming: distance per lap + number of laps
  • Running: distance + start & end time
  • Biking: distance + start & end time
• Date picker (defaults to today)
• Swipe-to-delete entries

📊 Real-Time Statistics

Each sport shows:

• Total distance
• Calories burned
• Time spent (for running & biking)
• Sport-specific KPIs

📈 Visualizations

• Tab-based layout:
  • Entries list
  • Graphs & statistics
• Charts powered by fl_chart

🏆 Badge System

• Unified badge system across all sports
• Badges unlock dynamically based on activity history
• Badges are revoked if requirements are no longer met
• Horizontally scrollable badge row
• Badge row only appears when at least one badge is unlocked

💾 Offline Persistence

• All data stored locally using shared_preferences
• No backend required
• Data persists across app restarts

🧱 App Architecture

lib/
├── components/
│   ├── swimming.dart
│   ├── running.dart
│   ├── biking.dart
│   └── shared_widgets/
├── models/
│   ├── swim_entry.dart
│   ├── run_entry.dart
│   ├── biking_entry.dart
│   ├── badge.dart
│   ├── badge_type.dart
│   └── models.dart
├── utils/
│   └── chart_helpers.dart
├── main.dart

🧩 Sport Modules

🏊 Swimming

• Lap-based tracking (25m / 50m)
• Automatic distance & calorie calculation
• Distance & calorie trend charts
• Badge unlocks based on distance and consistency

🏃 Running

• Distance input
• Start & end time selection
• Automatic duration calculation
• Time-based statistics and badges

🚴 Biking

• Distance input
• Start & end time selection
• Total ride duration tracking
• Calories, distance & time overview

🧮 Calculations

Calories

Calories are calculated per sport using configurable constants:

calories = distance (meters) × kcalPerMeter

Duration (Running & Biking)

• Calculated using start and end time
• Handles overnight activities automatically

🏆 Badge Rules

• Badges are defined centrally
• Each badge:
  • Has a BadgeType
  • Implements an isUnlocked(List<Entry>) rule
• Badge state is recalculated whenever entries are added or removed

Example Badge Definition

BadgeDefinition( type: BadgeType.firstWorkout, title: 'First Workout', isUnlocked: (entries) => entries.isNotEmpty, )

🧰 Dependencies

flutter: sdk: flutter shared_preferences: ^2.x.x fl_chart: ^0.66.x

🖼 Assets

flutter: assets: - assets/images/swimming.png - assets/images/running.png - assets/images/bike_riding.png

🚀 Roadmap / Future Improvements

• Weekly & monthly summaries
• Advanced analytics (pace, speed, averages)
• Sport-specific badge categories
• Cloud sync & authentication
• Data export (CSV / JSON)
• Dark mode support

🛠 Tech Stack

• Flutter
• Material Design
• Stateful Widgets
• Local persistence
• Modular component architecture

📄 License

This project is intended for personal and educational use.
You are free to modify, extend, and adapt it to your needs.