[Gtk2hs-users] Strange Gtk warning information.

[Andy S. <laz...@gm...>]

Hi all,

I always got information "(Manatee:1945): Gtk-CRITICAL **:
gtk_label_set_text: assertion `GTK_IS_LABEL (label)' failed" when i run
my application.

I found the problem is occur callback function
`stringBufferDisplayPositionStatus`.

------------------------------> Function stringBufferDisplayPositionStatus start <------------------------------
-- | Display position information.
stringBufferDisplayPositionStatus :: StringBuffer -> IO ()
stringBufferDisplayPositionStatus sb = 
  liftM2 (printf "Ln %3d, Col %3d ") (stringBufferGetLine sb) (stringBufferGetColumn sb)
             >>= statusbarInfoSubitemSetText (stringBufferStatusbar sb)
  >> return ()
------------------------------> Function stringBufferDisplayPositionStatus end   <------------------------------

Function `stringBufferDisplayPositionStatus` is a callback function that
when i type something in SourceView.

Function `statusbarInfoSubitemSetText` is for update statusbar
information, it implement in file Statusbar.hs.

------------------------------> Statusbar.hs start <------------------------------
module Manatee.Statusbar where

import Control.Monad
import Control.Monad.Trans

import Graphics.UI.Gtk hiding (Statusbar)

import qualified Graphics.UI.Gtk.Display.Statusbar as S

type StatusbarSubitem = S.Statusbar

data Statusbar =
    Statusbar {statusbarOutputSubitem
              ,statusbarInfoSubitem   :: StatusbarSubitem
              }

-- | Create new statusbar.
statusbarNew :: BoxClass b => b -> IO Statusbar
statusbarNew b = do
  let box = toBox b

  -- Status box for contain status boxes.
  statusBox <- hBoxNew False 0
  boxPackStart box statusBox PackNatural 0

  let subitem = statusbarSubitemNew statusBox
  liftM2 Statusbar subitem subitem

-- | Create new sub-statusbar.
statusbarSubitemNew :: BoxClass b => b -> IO StatusbarSubitem
statusbarSubitemNew b = do
  let box = toBox b

  bar <- S.statusbarNew
  statusbarSetHasResizeGrip bar False -- don't show resize grip
  boxPackStart box bar PackGrow 0     -- use PackGrow for grow size

  return bar

-- | Update output status.
statusbarOutputSubitemSetText :: Statusbar -> String -> IO Bool
statusbarOutputSubitemSetText sb str = 
    statusbarSubitemSetText (statusbarOutputSubitem sb) str

-- | Update info status.
statusbarInfoSubitemSetText :: Statusbar -> String -> IO Bool
statusbarInfoSubitemSetText sb str = 
    statusbarSubitemSetText (statusbarInfoSubitem sb) str

-- | Set text internal.
statusbarSubitemSetText :: StatusbarSubitem -> String -> IO Bool
statusbarSubitemSetText ss str = do
  id <- statusbarGetContextId ss str
  statusbarPush ss id str
  return False
------------------------------> Statusbar.hs end   <------------------------------
 
And strange is i never use label in my application, why Gtk will output
"(Manatee:1945): Gtk-CRITICAL **: gtk_label_set_text: assertion
`GTK_IS_LABEL (label)' failed"?

I missing something?

Thanks!

  -- Andy