Hi Marius, Thanks for the quick update. The xhtml returned from the listFilesInDir() is actually sent as a message to a display CometActor which renders the xhtml it receives within a specific <div> tag. So in essence we have these multiple feature threads running(the one in question is intended to be a local file manager feature) which generates xhtml for different functions which are then sent to this one display CometActor which displays it. So we intend to handle multi-feature tasking by running just the one CometActor and not multiples of them which obviously is a problem for lift(since the max no. of CometActors in a page is 2).
But back to your explanation of the S context getting lost, I think I understand what you mean regarding the session context. But does it also apply for SHtml generator methods?? I mean, does SHtml generator methods depend on the state of the session?? Another question I have is - even if SHtml generator methods fail to co-relate the session, shouldn't SHtml generator methods return?? or throw an exception? I don't know if you happened to use the exact same function in a LiftActor object or not, but if you do that you'll see that the function just doesn't return. Also, I don't intend to maintain state preservation. I just want to create a list of <a href> tags for all files which when clicked should make an Ajax call to a specific function in the LiftActor thread which processes the selection. Could you suggest some alternative way I could go about this with the current architecture(1 comet actor for display and individual feature-specific LiftActors sending xhtml to CometActor for rendering)?? Thanks, Soumik On Feb 16, 1:16 pm, Marius <[email protected]> wrote: > Well so you're using it from your own actor. I would not recommend > this due to state preservation. I mean S context is very likely lost > because your LiftActor is running on a different thread. What you need > is to pass the LiftSession instance to your LiftActor say using some > distinct message like: > > case class Init(session: LiftSession) > > then in your messageHandler > > protected def messageHandler = { > case FileManagerMsg(someMsg) => > { > S.initIfNotInitted(session) { > var fileList = listFilesInDir("/Users/soumik/Movies/") > Log.info("OUTPUT: " + fileList) > } > } > > } > > But I'm not sure from your code wht you do with the output of your > listFilesInDir since that never gets to be rendered. > > I strongly recommend using CometActor whenever you want to render > something asynchronously. It does a lots of good things for you. > > Br's, > Marius > > On Feb 16, 9:33 am, soumik <[email protected]> wrote: > > > Hi Marius, > > > Thanks for your response. I'm sorry for mis-communicating my problem > > earlier. As you pointed out the problem doesn't occur when the call to > > the function is made from a CometActor. > > In my case too, it was not a CometActor. Rather, it was the LiftActor. > > (Sometime back we had different CometActors for different feature > > threads, now we have 1 single CometActor which takes care of the > > display and different LiftActor threads which do the feature related > > stuff. Hence the confusion on my part). > > > Anyways, here's the relevant code: > > ------------------------------------- > > object TheVideoPlayerThread extends LiftActor > > { > > val threadName = "FileManager" > > > def listFilesInDir(dirName:String): NodeSeq = > > { > > Log.info("Recursing for: " + dirName) > > val files = (new java.io.File(dirName)).listFiles > > > def showFile1() = "AAA" > > > <li class="fileElem" id="dir">{dirName}</li> > > <ul> > > {files.flatMap(f => { > > if (f.isDirectory()) > > { > > Log.info("Directory: " + f.toString) > > listFilesInDir(f.toString) > > } > > else > > { > > Log.info("Regular file: " + f.getName) > > <li class="fileElem" id="regfile"> > > {SHtml.link("", () => showFile1, > > Text(f.getName)) } //This is the line causing the > > issue > > </li> > > } > > } > > )} > > </ul> > > } > > > protected def messageHandler = { > > case FileManagerMsg(someMsg) => > > { > > var fileList = listFilesInDir("/Users/soumik/Movies/") > > Log.info("OUTPUT: " + fileList) > > } > > } > > ------------------------------------- > > (I've omitted some of code in this thread which are not related to the > > file listing functionality.) > > The problem I see is as soon as I encounter the first file in the > > directory specified, it prints - "Regular file: <filename>", but after > > that I don't see the log - "OUTPUT - ...". The function never returns. > > Same function works perfectly in a CometActor and I see the nodeseq of > > files in <li> tags to be rendered. > > Also in the same method in my LiftActor object, if I replace the line: > > {SHtml.link("", () => showFile1, Text(f.getName)) } > > with just > > {f.getName} > > I see the function return and print the log "OUTPUT - .." with the > > list of all the files as <li> entries. > > > I'm sorry I couldn't give a more concrete example which you could run > > and reproduce the issue. I'll appreciate if you could just give this > > function a try from any LiftActor object and check the output on > > console. > > Also, I'm still on 1.1-SNAPSHOT. I've a fairly big codebase, so not > > sure if migrating to 2.0-SNAPSHOT will cause any other issues, > > particularly with jquery(i'm using lot of jquery plugins dependent on > > 1.3.2, not sure if all of them works nicely with 1.4). > > > Thanks, > > Soumik > > > On Feb 15, 11:22 pm, Marius <[email protected]> wrote: > > > > I don't think the cause is in SHtml. I tried your code from a snippet > > > and from a Comet actor and there was no lock whatsoever. But I did use > > > lift 2.0-SNAPSHOT. can you try with 2.0-SNAPSHOT ? > > > > Br's, > > > Marius > > > > On 15 feb., 15:20, soumik <[email protected]> wrote: > > > > > Hi, > > > > I'm using 1.1-SNAPSHOT lift release and am experiencing strange > > > > behaviour when trying to output a NodeSeq formed from nested NodeSeq & > > > > Scala code. > > > > > To highlight the problem let me show you the code I'm trying to > > > > execute: > > > > ----------------------------------- > > > > def listFilesInDir(dirName:String): NodeSeq = > > > > { > > > > Log.info("Recursing for: " + dirName) > > > > val files = (new java.io.File(dirName)).listFiles > > > > > def playFile1() = "AAA" > > > > > <li class="fileElem" id="dir">{dirName}</li> > > > > <ul> > > > > {files.flatMap(f => { > > > > if (f.isDirectory()) > > > > { > > > > Log.info("Directory: " + f.toString) > > > > listFilesInDir(f.toString) > > > > <span></span> > > > > } > > > > else > > > > { > > > > Log.info("Regular file: " + f.getName) > > > > <li class="fileElem" id="regfile"> > > > > {SHtml.link("", () => playFile1, > > > > Text("Something")) } /* Problem in this line */ > > > > </li> > > > > } > > > > } > > > > )} > > > > </ul> > > > > ----------------------------------- > > > > I'm trying to render the output of the above function in a comet > > > > actor. The problem i see is with the highlighted line of code. When > > > > the execution reaches this line of code, it gets stuck; the function > > > > doesn't return and i don't get a NodeSeq to render. > > > > However, for some reason if I change the highlighted line of code to > > > > say: > > > > {f.getName} > > > > I get the proper NodeSeq which lists all the files in the directory. > > > > > Seems to me that the SHtml class functions are encountering an error > > > > scenario(frm which its unable to recover). I've tried a couple of > > > > SHtml functions(a, text, link, submit etc.) all of them show the same > > > > problem, but if I use some other scala code it executes properly. > > > > > Could anyone look into this and verify whether this is indeed a bug > > > > with the SHtml functions? > > > > > Thanks, > > > > Soumik -- You received this message because you are subscribed to the Google Groups "Lift" group. To post to this group, send email to [email protected]. 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