🌦️ WeatherApp - Modern Android MVVM Architecture

A clean, modern, and production-ready Android application that displays real-time weather information and a 7-day forecast using the OpenWeatherMap API. Built with Kotlin and following modern Android development practices, this project showcases a robust implementation of the MVVM (Model-View-ViewModel) architectural pattern.

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🚀 Key Features

• Real-time Weather Data: Fetches live temperature, humidity, wind speed, and weather descriptions.
• Dynamic Themes: Automatically switches the app UI background and weather icons (e.g., Sunny/Cloudy/Rainy) based on current weather conditions.
• 7-Day Forecast: Displays a clean forecast list using a dynamic RecyclerView.
• Robust Error Handling: Professional status code handling (401, 404, etc.) and explicit network connectivity checks via a generic sealed class state management system.

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🛠️ Tech Stack & Dependencies

This project leverages the official Android Jetpack libraries and modern networking tools:

• Language: Kotlin
• Architecture: MVVM (Model-View-ViewModel)
• Networking: Retrofit2 & Gson Converter (Type-safe HTTP client & JSON parser)
• HTTP Logging: OkHttp Logging Interceptor (For inspecting network requests in Logcat)
• Asynchronous Processing: Kotlin Coroutines (Non-blocking network requests)
• Jetpack Components:
  • ViewModel (Retains UI data through configuration changes)
  • LiveData (Lifecycle-aware data observation)
  • View Binding (Null-safe UI component interaction)

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📂 Project Folder Structure

The code-base follows a strict layer-by-feature / layer-by-type separation to ensure clean boundaries, scalability, and ease of testing.

com.example.weatherapp/
│
├── data/                         # Data Layer (Network, Models, Repositories)
│   ├── model/                    # Pure Kotlin Data Classes mapped from JSON Response
│   │   ├── Clouds.kt
│   │   ├── Coord.kt
│   │   ├── Main.kt
│   │   ├── Sys.kt
│   │   ├── Weather.kt
│   │   ├── WeatherResponse.kt    # Root API response model
│   │   └── Wind.kt
│   │
│   ├── remote/                   # Network Configuration Components
│   │   ├── WeatherApiService.kt  # Retrofit Endpoint definitions interface
│   │   └── RetrofitClient.kt     # Singleton OkHttpClient & Retrofit provider
│   │
│   └── repository/               # Single Source of Truth for Data Operations
│       └── WeatherRepository.kt  # Handles API logic and maps responses to States
│
├── ui/                           # UI Layer (Activities, ViewModels, Adapters)
│   ├── adapter/
│   │   └── ForecastAdapter.kt    # RecyclerView Adapter using View Binding for 7-day list
│   │
│   └── weather/
│       ├── WeatherActivity.kt    # Renders UI, handles clicks, and observes ViewModel
│       └── WeatherViewModel.kt   # Communicates with Repository using Coroutines & updates LiveData
│
└── utils/                        # Shared Helpers & Utility Components
    ├── Constants.kt              # App-wide fixed configurations (BASE_URL, API_KEY, Units)
    └── Resource.kt               # Generic Sealed Class for managing API States (Loading, Success, Error)