1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
|
{-# LANGUAGE FlexibleInstances, MultiParamTypeClasses, PatternGuards, TypeSynonymInstances, DeriveDataTypeable #-}
-- --------------------------------------------------------------------------
-- |
-- Module : XMonad.Layout
-- Copyright : (c) Spencer Janssen 2007
-- License : BSD3-style (see LICENSE)
--
-- Maintainer : spencerjanssen@gmail.com
-- Stability : unstable
-- Portability : not portable, Typeable deriving, mtl, posix
--
-- The collection of core layouts.
--
-----------------------------------------------------------------------------
module XMonad.Layout (
Full(..), Tall(..), Mirror(..),
Resize(..), IncMasterN(..), Choose, (|||), ChangeLayout(..),
mirrorRect, splitVertically,
splitHorizontally, splitHorizontallyBy, splitVerticallyBy,
tile
) where
import XMonad.Core
import Graphics.X11 (Rectangle(..))
import qualified XMonad.StackSet as W
import Control.Arrow ((***), second)
import Control.Monad
import Data.Maybe (fromMaybe)
------------------------------------------------------------------------
-- | Change the size of the master pane.
data Resize = Shrink | Expand deriving Typeable
-- | Increase the number of clients in the master pane.
data IncMasterN = IncMasterN !Int deriving Typeable
instance Message Resize
instance Message IncMasterN
-- | Simple fullscreen mode. Renders the focused window fullscreen.
data Full a = Full deriving (Show, Read)
instance LayoutClass Full a
-- | The builtin tiling mode of xmonad. Supports 'Shrink', 'Expand' and
-- 'IncMasterN'.
data Tall a = Tall { tallNMaster :: !Int -- ^ The default number of windows in the master pane (default: 1)
, tallRatioIncrement :: !Rational -- ^ Percent of screen to increment by when resizing panes (default: 3/100)
, tallRatio :: !Rational -- ^ Default proportion of screen occupied by master pane (default: 1/2)
}
deriving (Show, Read)
-- TODO should be capped [0..1] ..
-- a nice pure layout, lots of properties for the layout, and its messages, in Properties.hs
instance LayoutClass Tall a where
pureLayout (Tall nmaster _ frac) r s = zip ws rs
where ws = W.integrate s
rs = tile frac r nmaster (length ws)
pureMessage (Tall nmaster delta frac) m =
msum [fmap resize (fromMessage m)
,fmap incmastern (fromMessage m)]
where resize Shrink = Tall nmaster delta (max 0 $ frac-delta)
resize Expand = Tall nmaster delta (min 1 $ frac+delta)
incmastern (IncMasterN d) = Tall (max 0 (nmaster+d)) delta frac
description _ = "Tall"
-- | Compute the positions for windows using the default two-pane tiling
-- algorithm.
--
-- The screen is divided into two panes. All clients are
-- then partioned between these two panes. One pane, the master, by
-- convention has the least number of windows in it.
tile
:: Rational -- ^ @frac@, what proportion of the screen to devote to the master area
-> Rectangle -- ^ @r@, the rectangle representing the screen
-> Int -- ^ @nmaster@, the number of windows in the master pane
-> Int -- ^ @n@, the total number of windows to tile
-> [Rectangle]
tile f r nmaster n = if n <= nmaster || nmaster == 0
then splitVertically n r
else splitVertically nmaster r1 ++ splitVertically (n-nmaster) r2 -- two columns
where (r1,r2) = splitHorizontallyBy f r
--
-- Divide the screen vertically into n subrectangles
--
splitVertically, splitHorizontally :: Int -> Rectangle -> [Rectangle]
splitVertically n r | n < 2 = [r]
splitVertically n (Rectangle sx sy sw sh) = Rectangle sx sy sw smallh :
splitVertically (n-1) (Rectangle sx (sy+fromIntegral smallh) sw (sh-smallh))
where smallh = sh `div` fromIntegral n --hmm, this is a fold or map.
-- Not used in the core, but exported
splitHorizontally n = map mirrorRect . splitVertically n . mirrorRect
-- Divide the screen into two rectangles, using a rational to specify the ratio
splitHorizontallyBy, splitVerticallyBy :: RealFrac r => r -> Rectangle -> (Rectangle, Rectangle)
splitHorizontallyBy f (Rectangle sx sy sw sh) =
( Rectangle sx sy leftw sh
, Rectangle (sx + fromIntegral leftw) sy (sw-fromIntegral leftw) sh)
where leftw = floor $ fromIntegral sw * f
-- Not used in the core, but exported
splitVerticallyBy f = (mirrorRect *** mirrorRect) . splitHorizontallyBy f . mirrorRect
------------------------------------------------------------------------
-- | Mirror a layout, compute its 90 degree rotated form.
newtype Mirror l a = Mirror (l a) deriving (Show, Read)
instance LayoutClass l a => LayoutClass (Mirror l) a where
runLayout (W.Workspace i (Mirror l) ms) r = (map (second mirrorRect) *** fmap Mirror)
`fmap` runLayout (W.Workspace i l ms) (mirrorRect r)
handleMessage (Mirror l) = fmap (fmap Mirror) . handleMessage l
description (Mirror l) = "Mirror "++ description l
-- | Mirror a rectangle.
mirrorRect :: Rectangle -> Rectangle
mirrorRect (Rectangle rx ry rw rh) = Rectangle ry rx rh rw
------------------------------------------------------------------------
-- LayoutClass selection manager
-- Layouts that transition between other layouts
-- | Messages to change the current layout.
data ChangeLayout = FirstLayout | NextLayout deriving (Eq, Show, Typeable)
instance Message ChangeLayout
-- | The layout choice combinator
(|||) :: (LayoutClass l a, LayoutClass r a) => l a -> r a -> Choose l r a
(|||) = Choose L
infixr 5 |||
-- | A layout that allows users to switch between various layout options.
data Choose l r a = Choose LR (l a) (r a) deriving (Read, Show)
-- | Are we on the left or right sub-layout?
data LR = L | R deriving (Read, Show, Eq)
data NextNoWrap = NextNoWrap deriving (Eq, Show, Typeable)
instance Message NextNoWrap
-- | A small wrapper around handleMessage, as it is tedious to write
-- SomeMessage repeatedly.
handle :: (LayoutClass l a, Message m) => l a -> m -> X (Maybe (l a))
handle l m = handleMessage l (SomeMessage m)
-- | A smart constructor that takes some potential modifications, returns a
-- new structure if any fields have changed, and performs any necessary cleanup
-- on newly non-visible layouts.
choose :: (LayoutClass l a, LayoutClass r a)
=> Choose l r a-> LR -> Maybe (l a) -> Maybe (r a) -> X (Maybe (Choose l r a))
choose (Choose d _ _) d' Nothing Nothing | d == d' = return Nothing
choose (Choose d l r) d' ml mr = f lr
where
(l', r') = (fromMaybe l ml, fromMaybe r mr)
lr = case (d, d') of
(L, R) -> (hide l' , return r')
(R, L) -> (return l', hide r' )
(_, _) -> (return l', return r')
f (x,y) = fmap Just $ liftM2 (Choose d') x y
hide x = fmap (fromMaybe x) $ handle x Hide
instance (LayoutClass l a, LayoutClass r a) => LayoutClass (Choose l r) a where
runLayout (W.Workspace i (Choose L l r) ms) =
fmap (second . fmap $ flip (Choose L) r) . runLayout (W.Workspace i l ms)
runLayout (W.Workspace i (Choose R l r) ms) =
fmap (second . fmap $ Choose R l) . runLayout (W.Workspace i r ms)
description (Choose L l _) = description l
description (Choose R _ r) = description r
handleMessage lr m | Just NextLayout <- fromMessage m = do
mlr' <- handle lr NextNoWrap
maybe (handle lr FirstLayout) (return . Just) mlr'
handleMessage c@(Choose d l r) m | Just NextNoWrap <- fromMessage m =
case d of
L -> do
ml <- handle l NextNoWrap
case ml of
Just _ -> choose c L ml Nothing
Nothing -> choose c R Nothing =<< handle r FirstLayout
R -> choose c R Nothing =<< handle r NextNoWrap
handleMessage c@(Choose _ l _) m | Just FirstLayout <- fromMessage m =
flip (choose c L) Nothing =<< handle l FirstLayout
handleMessage c@(Choose d l r) m | Just ReleaseResources <- fromMessage m =
join $ liftM2 (choose c d) (handle l ReleaseResources) (handle r ReleaseResources)
handleMessage c@(Choose d l r) m = do
ml' <- case d of
L -> handleMessage l m
R -> return Nothing
mr' <- case d of
L -> return Nothing
R -> handleMessage r m
choose c d ml' mr'
|
