以下程序无法按预期工作:
module Main where
import Graphics.UI.Gtk
import Control.Monad.IO.Class (liftIO)
import Control.Concurrent (forkIO)
main = do
unsafeInitGUIForThreadedRTS
window <- windowNew
windowSetDefaultSize window 200 200
label <- labelNew (Just "Hello")
forkIO (postGUISync (containerAdd window label))
on window deleteEvent (liftIO mainQuit >> return True)
widgetShowAll window
mainGUI
标签不会添加到窗口中。我用 -thread 编译。我做错了吗?