Just wrapped up a "prototype" evaluation of Compose Multiplatform. I've heard great things about the...

# compose

[Tyler Maginnis]

Just wrapped up a "prototype" evaluation of Compose Multiplatform. I've heard great things about the framework, and I've even got the cross-compilation to work on iOS, Android and Desktop targets - but I am running into an issue when attempting to implement the wasmJsMain target. I have an interface expect/fun factory pattern for TimeProvider.kt and TimeProviderFactory.kt .. .

TimeProvider.kt:

package org.example.project

// Import the JavaScript 'Date.now()' function
@JsImport("Date.now", "Date")
external fun jsDateNow(): Double

// Top-level function that calls the imported JavaScript function
@JsExport
fun currentTimeMillis(): Long = jsDateNow().toLong()

class WebTimeProvider : ITimeProvider {
    override fun getCurrentTimeMillis(): Long {
        return currentTimeMillis()
    }
}

TimeProviderFactory.kt:

package org.example.project

actual fun createTimeProvider(): ITimeProvider = WebTimeProvider()

[ephemient]

Have you read https://kotlinlang.org/docs/wasm-js-interop.html ?

[Tyler Maginnis]

Yes, but maybe I should read it again.

[ephemient]

also a lot of what you might want to interact with in a browser or Node environment may be covered by https://github.com/JetBrains/kotlin-wrappers already

[Tyler Maginnis]

That's really nice. I hadn't looked at this GH repo yet.

[Tyler Maginnis]

I think my confusion on this topic is how to import the wrapper package? do I need to add that to my build.gradle.kts?

[ephemient]

yes, as a normal dependency, e.g.

kotlin {
  sourceSets {
    wasmJsMain {
      dependencies {
        implementation("org.jetbrains.kotlin-wrappers:kotlin-node:22.10.2-pre.860")

[ephemient]

well probably not node for you if you're targeting Compose in a browser but you can find all the libraries and versions on GitHub, or just use them as inspiration to create your own wrappers

[ephemient]

oh wait I forgot, kotlin-wrappers is for JS

[ephemient]

for WasmJS you want there is also https://github.com/Kotlin/kotlinx-browser

[Tyler Maginnis]

Thanks, the web target is working now.