flutter_path_activity.kt

import io.flutter.embedding.android.FlutterActivity // there are two FlutterActivities :|
import io.flutter.plugins.GeneratedPluginRegistrant // this is not seen by IntelliJ by works ¯\_(ツ)_/¯

typealias FlutterCallback = (methodCall: MethodCall, result: MethodChannel.Result) -> Unit

class FlutterPathActivity : FlutterActivity() {
    override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
        infix fun String.handles(callHandler: FlutterCallback) {
            MethodChannel(flutterEngine.dartExecutor, this).setMethodCallHandler(callHandler)
        }
        GeneratedPluginRegistrant.registerWith(flutterEngine) // is this handled by default, I guess no?

        val initialPath = intent.getStringExtra(ConstantsBase.KEY_FLUTTER_PATH) // avoid initalRoute

        navChannel handles navCallback(initialPath)
    }
}

private const val navChannel = "com.eyeem.app/nav"
private fun navCallback(initialPath: String): FlutterCallback {
    return { methodCall, result ->
        when (methodCall.method) {
            "getInitialPath" -> result.success(initialPath)
        }
    }
}