gistfile1.hs

import Graphics.X11.Xlib.Display (defaultRootWindow)
import Graphics.X11.Xlib.Types (Display)
import Graphics.X11.Xlib.Extras
import Graphics.X11.Xlib.Event
import Graphics.X11.Types ( Window, ButtonMask, Button, enterNotify, buttonPress, noEventMask, button1
                          , buttonRelease)
import Foreign ( pokeByteOff )
import Foreign.C.Types ( CInt )
import System.Posix.Unistd (usleep)

setButtonEvent :: XEventPtr -> Window -> Window -> Window ->
                  ButtonMask -> Button ->
                  CInt -> CInt -> CInt -> CInt -> Bool ->
                  IO ()
setButtonEvent p win root subwin state button x y xroot yroot sameScreen = do
  setKeyEvent p win root subwin 0 0 sameScreen
  (`pokeByteOff` 64) p (x :: CInt)
  (`pokeByteOff` 68) p (y :: CInt)
  (`pokeByteOff` 72) p (xroot :: CInt)
  (`pokeByteOff` 76) p (yroot :: CInt)
  (`pokeByteOff` 80) p state
  (`pokeByteOff` 84) p button
  return ()

setEnterEvent :: XEventPtr -> Window -> Window -> Window ->
                 Bool -> IO ()
setEnterEvent p win root subwin = setButtonEvent p win root subwin 0 3 x y xroot yroot
  where
    (x, y) = (1, 1)
    (xroot, yroot) = (x+1, y+20)

click :: Display -> Window -> (Int, Int) -> IO ()
click display window (x',y') = do
  allocaXEvent $ \e -> do
    setEventType e enterNotify
    setEnterEvent e window root subwin True
    sendEvent display window False noEventMask e
    setEventType e buttonPress
    setButtonEvent e window root subwin 0x10 button1 x y xroot yroot True
    sendEvent display window False noEventMask e
    usleep 100000
    setEventType e buttonRelease
    setButtonEvent e window root subwin 0x110 button1 x y xroot yroot True
    sendEvent display window False noEventMask e
  sync display False
  where root = defaultRootWindow display
        (xroot, yroot) = (x+1, y+20)
        subwin = 0
        (x,y) = (fromIntegral x', fromIntegral y')