#+title: Interfacing with window managers

Listed below are ways to interface xmobar with your window manager of
choice.

* Using the DBus IPC interface with XMonad

  Bind the key which should {,un}map xmobar to a dummy value. This is
  necessary for {,un}grabKey in xmonad.

  #+begin_src haskell
    ((0, xK_Alt_L), pure ())
  #+end_src

  Also, install =avoidStruts= layout modifier from =XMonad.Hooks.ManageDocks=

  Finally, install these two event hooks (=handleEventHook= in =XConfig=)
  =myDocksEventHook= is a replacement for =docksEventHook= which reacts on unmap
  events as well (which =docksEventHook= doesn't).

  #+begin_src haskell
    import qualified XMonad.Util.ExtensibleState as XS

    data DockToggleTime = DTT { lastTime :: Time } deriving (Eq, Show, Typeable)

    instance ExtensionClass DockToggleTime where
        initialValue = DTT 0

    toggleDocksHook :: Int -> KeySym -> Event -> X All
    toggleDocksHook to ks ( KeyEvent { ev_event_display = d
                                     , ev_event_type    = et
                                     , ev_keycode       = ekc
                                     , ev_time          = etime
                                     } ) =
            io (keysymToKeycode d ks) >>= toggleDocks >> return (All True)
        where
        toggleDocks kc
            | ekc == kc && et == keyPress = do
                safeSendSignal ["Reveal 0", "TogglePersistent"]
                XS.put ( DTT etime )
            | ekc == kc && et == keyRelease = do
                gap <- XS.gets ( (-) etime . lastTime )
                safeSendSignal [ "TogglePersistent"
                            , "Hide " ++ show (if gap < 400 then to else 0)
                            ]
            | otherwise = return ()

        safeSendSignal s = catchX (io $ sendSignal s) (return ())
        sendSignal    = withSession . callSignal
        withSession mc = connectSession >>= \c -> callNoReply c mc >> disconnect c
        callSignal :: [String] -> MethodCall
        callSignal s = ( methodCall
                        ( objectPath_    "/org/Xmobar/Control" )
                        ( interfaceName_ "org.Xmobar.Control"  )
                        ( memberName_    "SendSignal"          )
                    ) { methodCallDestination = Just $ busName_ "org.Xmobar.Control"
                        , methodCallBody        = map toVariant s
                        }

    toggleDocksHook _ _ _ = return (All True)

    myDocksEventHook :: Event -> X All
    myDocksEventHook e = do
        when (et == mapNotify || et == unmapNotify) $
            whenX ((not `fmap` (isClient w)) <&&> runQuery checkDock w) refresh
        return (All True)
        where w  = ev_window e
            et = ev_event_type e
  #+end_src