Jack, The issues you're seeing are not Lift related. You are not using Actors correctly. Please see Philipp Haller's preso on Actors: http://lamp.epfl.ch/~phaller/doc/ScalaActors.pdf
Please also look at the Actor chapters in Beginning Scala or Programming in Scala. Thanks, David On Wed, Nov 11, 2009 at 8:26 PM, Jack Widman <[email protected]> wrote: > David, > > I have attached my code. It runs but does not behave as I intended it to. > The code does a web search on the term "scala" and displays a list of URLs > of the results. Next to each URL it says "Page Length : -1". A process is > running in the background which takes each URL, goes out and gets the page > and takes the length of the page. The length of that page is then supposed > to immediately appear on the page next to that URL. I put the lengths on a > queue, as they come in, and I have the Comet page poll the queue and display > the results. It would probably be better to have the results send a message > to the Comet class so the page is only re-rendered when there is a change > but for now I am polling. > > I can see the lengths coming in and being put on the queue, but the Comet > page is not getting them till they are all retrieved. (This takes way too > long and nothing changes on the screen till its too late). I need them to > appear as they come in. Occasionally I can see a length being retrieved and > the Comet page finds it but even then it is not displayed until all the > lengths are in. I know this is not very clear but I think it will be clear > from the code. > > I also know there are a lot of places in the code which can be improved and > I welcome all of your input but what I would love is to have these numbers > appear on the page as they they are retrieved. I have been stumped by this > for a while and I suspect that somebody who knows Lift well might see the > problem right away. > > The class that retrieves the page lengths is called Calculator and the > queue is called SourceQueue. The classes are pretty small so hopefully it > will be clear what is going on. I want you to know I think it is incredible > how responsive you and the group are and I look forward to using Lift in the > future. > > Thanks so much. > > Jack > > > On Tue, Nov 10, 2009 at 1:27 AM, David Pollak < > [email protected]> wrote: > >> >> >> On Mon, Nov 9, 2009 at 10:10 PM, Jack Widman <[email protected]>wrote: >> >>> The only difference between your working code and mine is that mine has a >>> process in the background that is always running and puts Foo objects on a >>> queue whenever they are ready. Where can I start this long running process >>> so that it doesn't interfere with the lowPriority method that takes things >>> off the queue and rerenders the page. I tried starting the process in its >>> own Actor that I start in localSetup but it seems somehow to be blocking the >>> lowPriority method from doing its thing. >>> >> >> I have no idea what this means... sorry. >> >> Please post actual runnable code and we can help you debug. >> >> >>> >>> On Sun, Nov 8, 2009 at 11:35 PM, David Pollak < >>> [email protected]> wrote: >>> >>>> Jack, >>>> >>>> I reproduced your code and it seems to work fine. I've enclosed a >>>> working copy. >>>> >>>> Some comments about your code: >>>> >>>> - The foos variable and the foo variable may be getting confused in >>>> the code... the render method may be rendering the same thing based on >>>> the >>>> unchanging foos variable. >>>> - Doing null testing is a sign that you have logic errors in your >>>> code. I strongly recommend using either Box or Option for everything >>>> that >>>> can logically not contain a value/reference. If you're bridging out to >>>> Java >>>> code and are expecting null from the Java code, write a small bridge >>>> that >>>> will wrapper the Java return values in Box/Option. >>>> - You have a case class (Tick) that contains no parameters. Please >>>> use a case object instead. >>>> - Your Tick look is a spin loop. You fire a Tick message as part of >>>> processing the Tick message. I would suggest that if you're polling, >>>> that >>>> you have a reasonable poll interval, otherwise you'll starve your CPU. >>>> Further, having reRender on each loop through means that you're forcing >>>> a >>>> lot of bytes over the wire rather than only doing a reRender on changed >>>> values. >>>> >>>> Thanks, >>>> >>>> David >>>> >>>> On Sun, Nov 8, 2009 at 3:47 PM, Jack Widman <[email protected]>wrote: >>>> >>>>> Sorry. Here it is: As I said, I know that when render is called, >>>>> foo.getValue has the right value. But it does not show on the screen, >>>>> unless >>>>> I refresh the browser. >>>>> >>>>> package com.foo.comet >>>>> >>>>> import net.liftweb._ >>>>> import http._ >>>>> import js._ >>>>> import JsCmds._ >>>>> import net.liftweb.util._ >>>>> import net.liftweb.http._ >>>>> import _root_.scala.xml._ >>>>> import scala.actors._ >>>>> import com.authoritude.snippet._ >>>>> import scala.collection.mutable.Queue >>>>> import net.liftweb.http.SessionVar >>>>> >>>>> >>>>> class MyComet extends CometActor { >>>>> >>>>> override def defaultPrefix = Full("auth") >>>>> >>>>> private var foos = FooManager.getFoos >>>>> >>>>> def createDisplay(foos:List[Foo]):NodeSeq = { >>>>> <span id="go"><table> >>>>> { >>>>> for {foo <- foos} yield <tr><td>{foo.getValue}</td></tr> >>>>> } >>>>> >>>>> </table></span> >>>>> } >>>>> >>>>> def render = { bind("foo" -> createDisplay(foos)) } >>>>> >>>>> override def localSetup = { >>>>> super.localSetup >>>>> this ! Tick >>>>> } >>>>> >>>>> var foo:Foo = null >>>>> override def lowPriority = { >>>>> case Tick => { >>>>> foo=FooQueue.getLatest >>>>> if (foo!=null && foo.getValue > -1) { >>>>> blogs = FooManager.process(foo, foos) >>>>> } else if (foo!=null){ >>>>> foos = foos.remove((f:Foo)=>(f.id==foo.id)) >>>>> } >>>>> reRender(false) >>>>> this ! Tick >>>>> } >>>>> } >>>>> } >>>>> >>>>> case class Tick >>>>> >>>>> >>>>> >>>>> On Sun, Nov 8, 2009 at 5:31 AM, Timothy Perrett < >>>>> [email protected]> wrote: >>>>> >>>>>> >>>>>> Without posting your code it's going to be tough to help you. >>>>>> >>>>>> Cheers, Tim >>>>>> >>>>>> Sent from my iPhone >>>>>> >>>>>> On 8 Nov 2009, at 08:14, jack <[email protected]> wrote: >>>>>> >>>>>> > >>>>>> > By the way, I know that when render is called, all the variables >>>>>> have >>>>>> > the right values. I just don't see it on the screen unless I refresh >>>>>> > it. >>>>>> > >>>>>> > On Nov 8, 3:12 am, jack <[email protected]> wrote: >>>>>> >> I have a CometActor. render is called when it is supposed to be but >>>>>> I >>>>>> >> don't see the changes. If I refresh the page at anytime, I do see >>>>>> the >>>>>> >> changes. Any idea what might cause this? >>>>>> > > >>>>>> > >>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>>> -- >>>>> Jack Widman >>>>> >>>>> co-founder / cto, Authoritude, Inc. >>>>> >>>>> 203-641-9355 >>>>> >>>>> >>>>> >>>>> >>>> >>>> >>>> -- >>>> Lift, the simply functional web framework http://liftweb.net >>>> Beginning Scala http://www.apress.com/book/view/1430219890 >>>> Follow me: http://twitter.com/dpp >>>> Surf the harmonics >>>> >>>> >>>> >>>> >>> >>> >>> -- >>> Jack Widman >>> >>> co-founder / cto, Authoritude, Inc. >>> >>> 203-641-9355 >>> >>> >>> >> >> >> -- >> Lift, the simply functional web framework http://liftweb.net >> Beginning Scala http://www.apress.com/book/view/1430219890 >> Follow me: http://twitter.com/dpp >> Surf the harmonics >> >> >> > > > > > > > -- Lift, the simply functional web framework http://liftweb.net Beginning Scala http://www.apress.com/book/view/1430219890 Follow me: http://twitter.com/dpp Surf the harmonics --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Lift" group. 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