Add Actions.MouseResize: a layout modifier to resize windows with the mouse

XMonad/Actions/MouseResize.hs

@@ -0,0 +1,119 @@
+{-# LANGUAGE GeneralizedNewtypeDeriving, MultiParamTypeClasses, PatternGuards, TypeSynonymInstances #-}
+
+-----------------------------------------------------------------------------
+-- |
+-- Module      :  XMonad.Actions.MouseResize
+-- Copyright   :  (c) 2007 Andrea Rossato
+-- License     :  BSD-style (see xmonad/LICENSE)
+--
+-- Maintainer  :  andrea.rossato@unibz.it
+-- Stability   :  unstable
+-- Portability :  unportable
+--
+-- A layout modifier to resize windows with the mouse by grabbing the
+-- window's lower right corner.
+--
+-- This module must be used together with "XMonad.Layout.WindowArranger".
+-----------------------------------------------------------------------------
+
+module XMonad.Actions.MouseResize
+    ( -- * Usage:
+      -- $usage
+      mouseResize
+    , MouseResize (..)
+    ) where
+
+import Control.Monad
+
+import XMonad
+import XMonad.Layout.Decoration
+import XMonad.Layout.LayoutModifier
+
+import XMonad.Layout.WindowArranger
+import XMonad.Util.XUtils
+
+-- $usage
+-- Usually this module is used to create layouts, but you can also use
+-- it to resize windows in any layout, together with the
+-- "XMonad.Layout.WindowArranger". For usage example see
+-- "XMonad.Layout.SimpleFloat" or "XMonad.Layout.DecorationMadness".
+--
+-- You can use this module with the following in your
+-- @~\/.xmonad\/xmonad.hs@:
+--
+-- > import XMonad.Actions.MouseResize
+-- > import XMonad.Layout.WindowArranger
+--
+-- Then edit your @layoutHook@ by modifying a given layout:
+--
+-- > myLayouts = mouseResize $ windowArrange $ layoutHook defaultConfig
+--
+-- and then:
+--
+-- > main = xmonad defaultConfig { layoutHook = myLayouts }
+--
+-- For more detailed instructions on editing the layoutHook see:
+--
+-- "XMonad.Doc.Extending#Editing_the_layout_hook"
+
+mouseResize :: l a -> ModifiedLayout MouseResize l a
+mouseResize = ModifiedLayout (MR [])
+
+data MouseResize a = MR [((a,Rectangle),a)]
+instance Show (MouseResize a) where show        _ = []
+instance Read (MouseResize a) where readsPrec _ _ = []
+
+instance LayoutModifier MouseResize Window where
+    redoLayout (MR st) _ _ wrs
+        | [] <- st  = do nst <- filterM (liftM not . isDecoration . fst) wrs >>= initState
+                         return (wrs, Just $ MR nst)
+        | otherwise = do nst <- filterM (liftM not . isDecoration . fst) wrs >>= processState
+                         return (wrs, Just $ MR nst)
+        where
+          initState    ws = mapM createInputWindow ws
+          processState ws = deleteWindows (map snd st) >> mapM createInputWindow ws
+
+    handleMess (MR s) m
+        | Just e <- fromMessage m :: Maybe Event = handleResize s e >> return Nothing
+        | Just Hide             <- fromMessage m = releaseResources >> return (Just $ MR [])
+        | Just ReleaseResources <- fromMessage m = releaseResources >> return (Just $ MR [])
+        where releaseResources = deleteWindows (map snd s)
+    handleMess _ _ = return Nothing
+
+handleResize :: [((Window,Rectangle),Window)] -> Event -> X ()
+handleResize st ButtonEvent { ev_window = ew, ev_event_type = et }
+    | et == buttonPress
+    , Just (w,Rectangle wx wy _ _) <- getWin ew st = do
+                                        focus w
+                                        mouseDrag (\x y -> do
+                                                     let rect = Rectangle wx wy
+                                                                (max 1 . fi $ x - wx)
+                                                                (max 1 . fi $ y - wy)
+                                                     sendMessage (SetGeometry rect)) (return ())
+
+      where
+        getWin w (((win,r),w'):xs)
+            | w == w'   = Just (win,r)
+            | otherwise = getWin w xs
+        getWin _ []     = Nothing
+handleResize _ _ = return ()
+
+createInputWindow :: (Window,Rectangle) -> X ((Window,Rectangle),Window)
+createInputWindow (w,r@(Rectangle x y wh ht)) = do
+  d  <- asks display
+  let rect = Rectangle (x + fi wh - 5) (y + fi ht - 5) 10 10
+  tw <- mkInputWindow d rect
+  io $ selectInput d tw (exposureMask .|. buttonPressMask)
+  showWindow tw
+  return ((w,r),tw)
+
+mkInputWindow :: Display -> Rectangle -> X Window
+mkInputWindow d (Rectangle x y w h) = do
+  rw <- asks theRoot
+  let screen   = defaultScreenOfDisplay d
+      visual   = defaultVisualOfScreen screen
+      attrmask = cWOverrideRedirect
+  io $ allocaSetWindowAttributes $
+         \attributes -> do
+           set_override_redirect attributes True
+           createWindow d rw x y w h 0 0 inputOnly visual attrmask attributes

xmonad-contrib.cabal

@@ -72,6 +72,7 @@ library
                         XMonad.Actions.FloatKeys
                         XMonad.Actions.FocusNth
                         XMonad.Actions.MouseGestures
+                        XMonad.Actions.MouseResize
                         XMonad.Actions.NoBorders
                         XMonad.Actions.RotSlaves
                         XMonad.Actions.Search