Expense Tracker

A simple and intuitive Android app to track your daily expenses and income. Built with Kotlin and Jetpack components.

Features

• Track Expenses & Income: Easily add, edit, and delete your financial transactions
• Category Management: Organize expenses by categories (Groceries, Entertainment, Travel, etc.)
• Custom Categories: Add your own categories beyond the defaults
• Monthly Overview: View expenses and income by month with easy navigation
• Category Drill-Down: Tap on any category to see all expenses under it
• Balance Summary: See your income, expenses, and balance at a glance
• Data Backup: Export and import your data as JSON files

Screenshots

Home Screen	Categories	Add Expense

Add Income	Month Picker

Tech Stack

• Language: Kotlin
• Architecture: MVVM (Model-View-ViewModel)
• Database: Room Persistence Library
• UI Components:
  • Material Design Components
  • ViewPager2 with TabLayout
  • RecyclerView with ListAdapter
  • CardView
• Async Operations: Kotlin Coroutines
• Lifecycle: LiveData, ViewModel

Project Structure

app/src/main/java/com/expensetracker/
├── data/
│   ├── AppDatabase.kt          # Room database setup
│   ├── Expense.kt              # Expense entity
│   ├── ExpenseDao.kt           # Expense data access object
│   ├── Income.kt               # Income entity
│   ├── IncomeDao.kt            # Income data access object
│   ├── Category.kt             # Category entity
│   ├── CategoryDao.kt          # Category data access object
│   ├── Repository.kt           # Data repository
│   └── BackupManager.kt        # Import/Export functionality
└── ui/
    ├── MainActivity.kt         # Main activity with tabs
    ├── MainViewModel.kt        # Shared ViewModel
    ├── ExpenseListFragment.kt  # Expenses list tab
    ├── IncomeListFragment.kt   # Income list tab
    ├── CategoryListFragment.kt # Categories tab
    ├── CategoryExpensesActivity.kt # Category drill-down
    ├── ExpenseAdapter.kt       # Expense list adapter
    ├── IncomeAdapter.kt        # Income list adapter
    ├── CategoryAdapter.kt      # Category list adapter
    └── ViewPagerAdapter.kt     # Tab adapter

Default Categories

• Groceries
• Entertainment
• Cab/Ride
• Restaurant
• Travel
• Gifts
• Utilities
• Shopping
• Health
• Other

Getting Started

Prerequisites

• Android Studio Arctic Fox or later
• Android SDK 21 or higher
• Kotlin 1.5+

Installation

1. Clone the repository:

   git clone https://github.com/yourusername/ExpenseTracker.git

2. Open the project in Android Studio

3. Sync Gradle and build the project

4. Run on an emulator or physical device

Usage

Adding an Expense

1. Tap the floating action button (+)
2. Enter the amount
3. Select a category from the dropdown
4. Add an optional description
5. Select the date
6. Tap "Save"

Viewing Category Breakdown

1. Navigate to the "Categories" tab
2. Tap on any category to see all expenses under it
3. Tap on an expense to edit it

Changing Month

• Use the left/right arrows in the header to navigate months
• Tap on the month name to open the month picker

Backup & Restore

1. Tap the settings icon (gear)
2. Choose "Export Data" to save to Downloads folder
3. Choose "Import Data" to restore from a JSON file

License

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

Contributing

1. Fork the repository
2. Create your feature branch (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request