Re: [Gtk2hs-users] clipboardRequestText

[Axel S. <Axe...@in...>]

On 04.05.2010, at 10:42, Christoph Bauer wrote:

> Hi Axel,
>
>> Hi Christoph,
>>
>> I might have misunderstood the semantics of clipboardRequestText. I
>> assumed that it blocks until the passed-in function was called. As a
>> consequence, I free the function pointer of the passed-in function
>> immediately after the C call to clipboard_request_text returns. It
>> seems that on my platform (MacOS) the primary clipboard does not work
>> as expected. Could you (a) confirm that the following program crashes
>> and (b) try to use clipboardRequestContents since this function frees
>> the reception function after it has been executed.
>>
>> Cheers,
>> Axel
>>
>> import Graphics.UI.Gtk
>> import Data.Char
>> main = do
>> initGUI
>> putStrLn "1"
>> clipboard <- clipboardGet selectionPrimary
>> putStrLn "2"
>> clipboardRequestText clipboard
>>         (\ mbS -> do
>>           putStrLn "3"
>>           case mbS of
>>             Nothing -> return ()
>>             Just s -> clipboardSetText clipboard (map toUpper s))
>
>
> (a) the program doesn't crash. I had to append a "mainGUI"
> to make it crash.

Oh, ok.

> (b)  I use now
>
>  clipboardRequestContents clipboard targetString
>          $ do
>              mbS <- selectionDataGetText
>              case mbS of
>                Nothing -> selectionDataSetText "ABC" >> return ()
>                Just s -> selectionDataSetText (translate s) >> return
>          ()
> I guess, getting the text works, but selectionDataSetText fails.
> Unfortunatly SelectionDataM is not an instace of MonadIO. So neither
> I can insert a liftIO . putStrLn nor I can call clipboarSetText.

Yes, it is instance of IO! You should be able to just liftIO IO- 
actions. liftIO is in Control.Monad.Trans.

Cheers,
Axel

> Regards,
> Christoph