[Gtk2hs-users] postGUIAsync

[Tim D. <tw...@do...>]

Hi,

If I add code to the progressthreadedrts.hs demo to log the thread ids,
it's not what I expect. The posted action seems to run in a thread
different each time. In the output below, each "posted" output gets a
different thread id. Is this expected?

Tim

import Graphics.UI.Gtk

import Control.Concurrent

main :: IO ()
main = do

  -- It is marked unsafe becuase it is your obligation to ensure you
  -- only call Gtk+ from one OS thread, or 'bad things' will happen.
  unsafeInitGUIForThreadedRTS
  logT "start"

  dia <- dialogNew
  dialogAddButton dia stockClose ResponseClose
  contain <- dialogGetUpper dia
  pb <- progressBarNew
  boxPackStartDefaults contain pb
  widgetShowAll dia
  forkIO (doTask pb)

  dialogRun dia
  return ()

logT :: String -> IO ()
logT msg = do
   tid <- myThreadId
   putStrLn (show tid ++ ": " ++ msg)

doTask :: ProgressBar -> IO ()
doTask pb = do
  logT "task"
  postGUIAsync $ do
     logT "posted"
     progressBarPulse pb
  threadDelay 100000
  doTask pb



----------------------------------

$ ./progressThreadedRTS 
ThreadId 3: start
ThreadId 4: task
ThreadId 5: posted
ThreadId 4: task
ThreadId 7: posted
ThreadId 4: task
ThreadId 9: posted
ThreadId 4: task
ThreadId 11: posted
ThreadId 4: task
ThreadId 13: posted
ThreadId 4: task
ThreadId 15: posted
ThreadId 4: task
ThreadId 17: posted
ThreadId 4: task
ThreadId 19: posted
ThreadId 4: task
ThreadId 21: posted