Setup

Setup FileKit Core in your Kotlin Multiplatform project

Installation

FileKit provides a platform-agnostic file abstraction called PlatformFile. It allows you to work with files in a platform-agnostic way. You can create, read, write, and delete files using the PlatformFile API.

You can use PlatformFile in your project by adding the following dependency:

build.gradle.kts

implementation("io.github.vinceglb:filekit-core:0.14.2")

[versions]
filekit = "0.14.2"

[libraries]
filekit-core = { module = "io.github.vinceglb:filekit-core", version.ref = "filekit" }

FileKit Core provides the fundamental file operations for your Kotlin Multiplatform project. It’s designed to work across all supported platforms with a unified API.

Platform-specific setup

FileKit Core is designed to work out of the box for most platforms, but some targets require additional setup.

Android setup

FileKit Core is automatically initialized in Android applications. It uses App Startup to initialize the library, ensuring that it is ready to use when your app starts.

If for some reason you want to disable App Startup in your app, you can initialize FileKit manually by calling FileKit.manualFileKitCoreInitialization(context) in your MainActivity or Application class.

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        // Initialize FileKit
        FileKit.manualFileKitCoreInitialization(this)
    }
}

JVM setup

FileKit needs to have your application id to handle the app directory. Your application id is generally the package name or the name of your application. FileKit will use this appId as app directory.

We recommend you to initialize FileKit in your main.kt file:

main.kt

fun main() {
  // Initialize FileKit
  FileKit.init(appId = "MyApplication")

  // Start your application
  application {
      Window(onCloseRequest = ::exitApplication) {
          // ...
      }
  }
}

The application ID is used to create user-specific directories on different operating systems:

• Windows: %APPDATA%\your.application.id\
• macOS: ~/Library/Application Support/your.application.id/
• Linux: ~/.local/share/your.application.id/

Custom Cache and Data Directories

For applications that need custom directory paths (e.g., portable applications or specific deployment scenarios), you can specify custom cache and data directories:

main.kt

fun main() {
  val appDir = File(System.getProperty("user.home"), ".myapp")
  FileKit.init(
      appId = "MyApplication",
      filesDir = File(appDir, "data"),
      cacheDir = File(appDir, "cache")
  )

  // ...
}

ProGuard Configuration

If you’re using ProGuard or code obfuscation on JVM platforms, add the relevant rules to your proguard-rules.pro:

# Required on JVM for JNA-based integrations.
-keep class com.sun.jna.** { *; }
-keep class * implements com.sun.jna.** { *; }

# Required when using FileKit Dialogs on Linux (XDG Desktop Portal / DBus).
-keep class org.freedesktop.dbus.** { *; }
-keep class io.github.vinceglb.filekit.dialogs.platform.xdg.** { *; }
-keepattributes Signature,InnerClasses,RuntimeVisibleAnnotations

iOS, macOS, JS, WASM setup

No additional setup is needed for iOS, macOS, JS, and WASM targets. FileKit Core works out of the box on these platforms.