Swing Actors using Akka

swingactors.scala

// ©2012 Viktor Klang

package akka.klang

import akka.dispatch.{ DispatcherPrerequisites, ExecutorServiceFactory, ExecutorServiceConfigurator }
import com.typesafe.config.Config
import java.util.concurrent.{ ExecutorService, AbstractExecutorService, ThreadFactory, TimeUnit }
import java.util.Collections
import javax.swing.SwingUtilities

// First we wrap invokeLater as an ExecutorService
object SwingExecutorService extends AbstractExecutorService { 
  def execute(command: Runnable) = SwingUtilities.invokeLater(command)
  def shutdown(): Unit = ()
  def shutdownNow() = Collections.emptyList[Runnable]
  def isShutdown = false
  def isTerminated = false
  def awaitTermination(l: Long, timeUnit: TimeUnit) = true
}

// Then we create an ExecutorServiceConfigurator so that Akka can use our SwingExecutorService for the dispatchers
class SwingEventThreadExecutorServiceConfigurator(config: Config, prerequisites: DispatcherPrerequisites) extends ExecutorServiceConfigurator(config, prerequisites) {
  private val f = new ExecutorServiceFactory { def createExecutorService: ExecutorService = SwingExecutorService }
  def createExecutorServiceFactory(id: String, threadFactory: ThreadFactory): ExecutorServiceFactory = f
}

// Then we simply need to create a dispatcher configuration in our application.conf

swing-dispatcher {
  type = "Dispatcher"
  executor = "akka.klang.SwingEventThreadExecutorServiceConfigurator"
  throughput = 1
}

// After that we just create the GUI Actors with a Props with the correct dispatcher set:

val frameActor = context.actorOf(Props[FrameActor].withDispatcher("swing-dispatcher"), "frame-actor")

// Done! Now all messages processed by "frameActor" will be executed by the Swing Event Dispatch Thread, enjoy!

Thank you. I have extended this gist to include JavaFX actors as suggested by this stackoverflow answer. It can be found here.

Could you explain where the g.draw() calls go? Does the frameActor gets created inside another actor? Thanks.

@drozzy you can call draw inside the FrameActor, and if you want to initiate a repaint from the outside, send the FrameActor a message to do so.

Could you explain a bit better what you are doing here? The goal is to have an actor that can execute itself from within the UI Thread, To what be able to manipulate the UI, without using Platform.RunLater?

I can't see how the FrameActor should be, can anyone give me a minimal example?