Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>If you want to use Actors, following may work for you. </p> <p>There are two actors:</p> <ul> <li><em>WorkerActor</em> which does data processing (here, there is simple loop with Thread.sleep). This actor sends messages about progress of work to another actor:</li> <li><em>GUIUpdateActor</em> - receives updates about progress and updates UI by calling <em>handleGuiProgressEvent</em> method</li> </ul> <p>UI update method <em>handleGuiProgressEvent</em> receives update event. Important point is that this method is called by Actor using one of Akka threads and uses Swing.onEDT to do Swing work in Swing event dispatching thread. </p> <p>You may add following to various places to see what is current thread.</p> <pre><code>println("Current thread:" + Thread.currentThread()) </code></pre> <p>Code is runnable Swing/Akka application.</p> <pre><code>import akka.actor.{Props, ActorRef, Actor, ActorSystem} import swing._ import event.ButtonClicked trait GUIProgressEventHandler { def handleGuiProgressEvent(event: GuiEvent) } abstract class GuiEvent case class GuiProgressEvent(val percentage: Int) extends GuiEvent object ProcessingFinished extends GuiEvent object SwingAkkaGUI extends SimpleSwingApplication with GUIProgressEventHandler { lazy val processItButton = new Button {text = "Process it"} lazy val progressBar = new ProgressBar() {min = 0; max = 100} def top = new MainFrame { title = "Swing GUI with Akka actors" contents = new BoxPanel(Orientation.Horizontal) { contents += processItButton contents += progressBar contents += new CheckBox(text = "another GUI element") } val workerActor = createActorSystemWithWorkerActor() listenTo(processItButton) reactions += { case ButtonClicked(b) =&gt; { processItButton.enabled = false processItButton.text = "Processing" workerActor ! "Start" } } } def handleGuiProgressEvent(event: GuiEvent) { event match { case progress: GuiProgressEvent =&gt; Swing.onEDT{ progressBar.value = progress.percentage } case ProcessingFinished =&gt; Swing.onEDT{ processItButton.text = "Process it" processItButton.enabled = true } } } def createActorSystemWithWorkerActor():ActorRef = { def system = ActorSystem("ActorSystem") val guiUpdateActor = system.actorOf( Props[GUIUpdateActor].withCreator(new GUIUpdateActor(this)), name = "guiUpdateActor") val workerActor = system.actorOf( Props[WorkerActor].withCreator(new WorkerActor(guiUpdateActor)), name = "workerActor") workerActor } class GUIUpdateActor(val gui:GUIProgressEventHandler) extends Actor { def receive = { case event: GuiEvent =&gt; gui.handleGuiProgressEvent(event) } } class WorkerActor(val guiUpdateActor: ActorRef) extends Actor { def receive = { case "Start" =&gt; { for (percentDone &lt;- 0 to 100) { Thread.sleep(50) guiUpdateActor ! GuiProgressEvent(percentDone) } } guiUpdateActor ! ProcessingFinished } } } </code></pre>
    singulars
    1. This table or related slice is empty.
    1. POAsynchronous UI update with Swing
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USArnost Valicek
    1. USArnost Valicek
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COThanks so much for this. It is so difficult to do anything with akka and actors for a newbie because of the lack (or excess) of documentation and also because there are different versions of the API. For now, I believe Futures does it exactly the way I want. I now feel Actors is a bit of an overkill for a UI
      singulars
      1. PO
      1. USPlasty Grove
    2. CONice one, thank you. FYI, I had to use `Props(classOf[GuiUpdateActor], this)` and `Props(classOf[WorkerActor], guiUpdateActor)`, respectively, as the first argument to each invocation of `system.actorOf()` (akka version 2.3-M2).
      singulars
      1. PO
      1. USAdam Mackler
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload