Advanced Search

wxHaskell multi-thread & custom event example

/ Published in: Haskell
Save to your folder(s)
This examples shows how to handle user-defined events in wxHaskell via menu events.

If the thread issues an event is not the main thread, use evtHandlerAddPendingEvent instead of evtHandlerProcessEvent.

Expand | Embed | Plain Text

Copy this code and paste it in your HTML 
  1. import EnableGUI -- from http://wxhaskell.sourceforge.net/download/EnableGUI.hs
  2.  
  3. import Graphics.UI.WXCore hiding (Var)
  4. import Graphics.UI.WX hiding (Var, enter)
  5. import Data.Bits ((.&.), complement)
  6.  
  7. myEventId = wxID_HIGHEST+1 -- the custom event ID
  8. -- the custom event is registered as a menu event
  9. createMyEvent = commandEventCreate wxEVT_COMMAND_MENU_SELECTED myEventId
  10. registerMyEvent win io = evtHandlerOnMenuCommand win myEventId io
  11.  
  12. gui
  13.   = do f <- frame [text := "custom event sample"]
  14.        bt <- button f [text := "click to invoke a custom event"]
  15.        set f [layout := column 1 [hfill (widget bt)]]
  16.        set bt [on command := onClick f]
  17.        registerMyEvent f (putStrLn "The custom event is fired!!")
  18.        return ()
  19.   where
  20.       onClick f
  21.         = do
  22.           ev <- createMyEvent
  23.           evtHandlerProcessEvent f ev
  24.           return ()
  25.  
  26.  
  27. main = enableGUI >> start gui

Report this snippet


Comments

RSS Icon Subscribe to comments

You need to login to post a comment.