/* Title: Tools/Graphview/mutator_event.scala
Author: Markus Kaiser, TU Muenchen
Author: Makarius
Events for dialog synchronization.
*/
package isabelle.graphview
import isabelle._
object Mutator_Event
{
sealed abstract class Message
case class Add(m: Mutator.Info) extends Message
case class New_List(m: List[Mutator.Info]) extends Message
type Receiver = PartialFunction[Message, Unit]
class Bus
{
private val receivers = Synchronized[List[Receiver]](Nil)
def += (r: Receiver): Unit = receivers.change(Library.insert(r))
def -= (r: Receiver): Unit = receivers.change(Library.remove(r))
def event(x: Message): Unit = receivers.value.reverse.foreach(r => r(x))
}
}