2017-05-27 109 views
0

Haskell-way多線程和wxWidgets的另一個問題。使用wxHaskell注入wxWigets事件循環的無窗口事件

我看到https://stackoverflow.com/a/12596595/4095104作爲一個很好的黑客運行在WX事件循環代碼,但它需要我start/run首先要創建一個窗口,從它返回,因此事件循環可以自生自滅,而我的應用程序是基本上不需要窗口,並且可以根據內部(多線程)邏輯的需求創建窗口。有沒有一種好的方法可以在循環中創建一個不綁定到任何已有的wxWidgets對象的新事件?

編輯:代碼示例:

import Graphics.UI.WX as WX 
import Graphics.UI.WXCore as WXCore 
import Control.Concurrent 

-- | cf. http://snipplr.com/view/17538/ 
myEventId :: Int 
myEventId = WXCore.wxID_HIGHEST+100 
    -- the custom event ID, avoid clash with Graphics.UI.WXCore.Types.varTopId 

-- | the custom event is registered as a menu event 
createMyEvent :: IO (WXCore.CommandEvent()) 
createMyEvent = 
    WXCore.commandEventCreate WXCore.wxEVT_COMMAND_MENU_SELECTED myEventId 

registerMyEvent :: WXCore.EvtHandler a -> IO() -> IO() 
registerMyEvent win io = 
    WXCore.evtHandlerOnMenuCommand win myEventId io 


doesntwork = do 
    handler <- newEmptyMVar 
    start $ do 
     app <- wxcAppGetApp 
     event <- createMyEvent 
     mvar <- newEmptyMVar 
     registerMyEvent app $ do 
      str <- takeMVar mvar 
      putStrLn str 
     putMVar handler (app, event, mvar) 
    (app, event, mvar) <- takeMVar handler 
    putMVar mvar "hack" 
    WXCore.evtHandlerAddPendingEvent app event 
    threadDelay 10000000000 

works = do 
    handler <- newEmptyMVar 
    start $ do 
     app <- wxcAppGetApp 
     event <- createMyEvent 
     mvar <- newEmptyMVar 
     registerMyEvent app $ do 
      str <- takeMVar mvar 
      putStrLn str 
     putMVar handler (app, event, mvar) 
     putMVar mvar "hack" 
     WXCore.evtHandlerAddPendingEvent app event 
    (app, event, mvar) <- takeMVar handler 
    threadDelay 10000000000 

main = doesntwork 

回答

0

在C++水平,你可以只使用wxEventLoop class直接,但我不知道它是否正確由wxHaskell包裹。