Compose Multiplatform Demo Project

This is a comprehensive project utilizing Compose Multiplatform for shared UI and Kotlin Multiplatform (KMP) for shared logic across Android, iOS, Web (Wasm/JS), Desktop (JVM), and a Ktor Server.

🚀 Project Structure

• :app:shared: The heart of the application. Contains shared Compose UI, ViewModels, and business logic.
  • commonMain: Core UI and logic shared by all targets.
  • androidMain, appleMain, jvmMain, webMain: Platform-specific implementations (e.g., NativeButton, DataStore initialization).
  • nonWebMain / nonJvmMain: Shared source sets for specific target groups (e.g., DataStore path logic).
• :app:androidApp: Android-specific entry point.
• :app:iosApp: Xcode project and SwiftUI entry point for iOS.
• :app:desktopApp: Entry point for the Compose Desktop application.
• :app:webApp: Entry point for the Web (Kotlin/Wasm & JS) application.
• :core: Shared utilities and domain models used by both the app and the server.
• :server: A Ktor-based backend server.

🛠 Technology Stack

Core & Multiplatform

• Kotlin Multiplatform (KMP): Shared business logic across all targets.
• Kotlinx Serialization: JSON parsing and data serialization.
• Kotlinx DateTime: Multiplatform date and time handling.
• Okio: File system and path management for shared storage.

User Interface (UI)

• Compose Multiplatform: Declarative UI for all platforms.
  • Material 3: Modern design system implementation.
  • Navigation Compose: Type-safe navigation in shared code.
• UIKit Interop: Integration of native iOS components (e.g., UIViewController).

Architecture & DI

• Koin: Dependency injection for shared and platform-specific modules.
• MVVM: Architecture using androidx.lifecycle.ViewModel in shared code.

Data & Networking

• Ktor Client: Asynchronous HTTP client (Darwin engine for iOS, OkHttp for Android/JVM).
• Jetpack DataStore: Persistent key-value storage (Preferences).

Backend

• Ktor Server: High-performance backend framework.
• Shared Core: Common models shared between the app and server.

🚀 Getting Started

Prerequisites

• Android Studio (latest stable or Koala+)
• Xcode (for iOS development)
• JDK 17 or higher

Running the Applications

Target	Command
Android	./gradlew :app:androidApp:assembleDebug
Desktop	./gradlew :app:desktopApp:run
Web (Wasm)	./gradlew :app:webApp:wasmJsBrowserDevelopmentRun
Server	./gradlew :server:run
iOS	Open app/iosApp/iosApp.xcodeproj in Xcode and run.

Build & Troubleshooting

If you encounter Wasm lock file issues:

./gradlew kotlinWasmUpgradeYarnLock

🧪 Testing

• Android: ./gradlew :app:shared:testAndroidHostTest
• Desktop: ./gradlew :app:shared:jvmTest
• Web: ./gradlew :app:shared:wasmJsTest
• iOS: ./gradlew :app:shared:iosSimulatorArm64Test
• Server: ./gradlew :server:test

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Built with ❤️ using Kotlin Multiplatform.