Forum Discussion

squirreltown's avatar
squirreltown
Roku Guru
12 years ago

No loop

Is there a way to get an Event, for instance an roAudioplayer status message without a message loop? Or to make a loop that loops once and exits?
I need to get the info at the start of a function, in the first couple of lines and have been unable to make a loop that doesn't take over and mess things up.

thanks
Roku Developer Program

3 Replies

  • destruk's avatar
    destruk
    Streaming Star
    12 years ago
    http://sdkdocs.roku.com/display/sdkdoc/Event+Loops

    "end while"/"exit while" exits a message loop. So if you have this code -


    port = CreateObject("roMessagePort")
    screen = CreateObject("roSpringboardScreen") 
    screen.SetMessagePort(port) ' instruct screen to send events to port
    screen.Show()
    while true
        msg = wait(0, port) ' wait for a message
        if type(msg) = "roSpringboardScreenEvent" then
            if msg.isScreenClosed() then
                return -1
            elseif msg.isButtonPressed()
                print "button pressed: ";msg.GetIndex()
            else
                ' ignore other unknown or uninteresting roSpringBoardScreenEvents
            endif
        else
            ' ignore other events, not type roSpringboardScreenEvent
        endif
    end while


    and you change it to


    port = CreateObject("roMessagePort")
    screen = CreateObject("roSpringboardScreen") 
    screen.SetMessagePort(port) ' instruct screen to send events to port
    screen.Show()
    while true
        msg = wait(0, port) ' wait for a message
        if type(msg) = "roSpringboardScreenEvent" then
            if msg.isScreenClosed() then
                return -1
            elseif msg.isButtonPressed()
                print "button pressed: ";msg.GetIndex()

                EXIT WHILE

            else
                ' ignore other unknown or uninteresting roSpringBoardScreenEvents
            endif
        else
            ' ignore other events, not type roSpringboardScreenEvent
        endif
    end while


    Then when a button is pressed it will leave the loop.
  • squirreltown's avatar
    squirreltown
    Roku Guru
    12 years ago
    Thank you destruk, those docs make a lot more sense after you explain something. I had tried the exit while , but i think i wasn't tying it to an event, i was just hoping it would exit on its own which it didn't seem to, or did but didn't exit properly. You really helped me out this morning, i appreciate it.
  • squirreltown's avatar
    squirreltown
    Roku Guru
    12 years ago
    Well in the end i got the same results as yesterday, that is any kind of loop, even the one you posted - prevents the springboard from reopening, and stops other things from working. Arrgg.