Merge pull request #684 from TheMC47/feature/workspace-screen

Export `WindowScreen` type and add a new module: `X.H.WorkspaceScreen`

CHANGES.md

@@ -40,6 +40,12 @@
     A wrapper around the 'ReadP' parser combinator, providing behaviour
     that's closer to the more popular parser combinator libraries.
 
+  * `XMonad.Hooks.StatusBar.WorkspaceScreen`
+
+    In multi-head setup, it might be useful to have screen information of the
+    visible workspaces combined with the workspace name, for example in a status
+    bar. This module provides utility functions to do just that.
+
 ### Bug Fixes and Minor Changes
 
   * `XMonad.Prompt.OrgMode`
@@ -121,6 +127,9 @@
     - Added `keymaskToString` and `keyToString` to show a key mask and a
       key in the style of `XMonad.Util.EZConfig`.
 
+    - Added `WindowScreen`, which is a type synonym for the specialized `Screen`
+      type, that results from the `WindowSet` definition in `XMonad.Core`.
+
   * `XMonad.Util.XUtils`
 
     - Added `withSimpleWindow`, `showSimpleWindow`, `WindowConfig`, and

XMonad/Actions/EasyMotion.hs

@@ -271,7 +271,7 @@ handleSelectWindow c = do
         $ M.elems
         $ M.mapWithKey (\sid ks -> buildOverlays ks <$> sortedOverlayWindows sid) m
      where
-      screenById :: ScreenId -> Maybe (W.Screen WorkspaceId (Layout Window) Window ScreenId ScreenDetail)
+      screenById :: ScreenId -> Maybe WindowScreen
       screenById sid = find ((== sid) . W.screen) (W.screens ws)
       visibleWindowsOnScreen :: ScreenId -> [Window]
       visibleWindowsOnScreen sid = filter (`elem` toList mappedWins) $ W.integrate' $ screenById sid >>= W.stack . W.workspace

XMonad/Actions/Navigation2D.hs

@@ -388,7 +388,7 @@ data Navigation2DConfig = Navigation2DConfig
   }
 
 -- | Shorthand for the tedious screen type
-type Screen = W.Screen WorkspaceId (Layout Window) Window ScreenId ScreenDetail
+type Screen = WindowScreen
 
 -- | Convenience function for enabling Navigation2D with typical keybindings.
 -- Takes a Navigation2DConfig, an (up, left, down, right) tuple, a mapping from

XMonad/Hooks/StatusBar/WorkspaceScreen.hs

@@ -0,0 +1,105 @@
+{-# LANGUAGE NamedFieldPuns #-}
+{-# LANGUAGE TypeApplications #-}
+
+{- |
+ Module      :  XMonad.Hooks.StatusBar.WorkspaceScreen
+ Description :  Combine workspace names with screen information
+ Copyright   :  (c) Yecine Megdiche <yecine.megdiche@gmail.com>
+ License     :  BSD3-style (see LICENSE)
+
+ Maintainer  :  Yecine Megdiche <yecine.megdiche@gmail.com>
+ Stability   :  unstable
+ Portability :  unportable
+
+ In multi-head setup, it might be useful to have screen information of the
+ visible workspaces combined with the workspace name, for example in a status
+ bar. This module provides utility functions to do just that.
+-}
+module XMonad.Hooks.StatusBar.WorkspaceScreen
+    (
+    -- * Usage
+    -- $usage
+      combineWithScreen
+    , combineWithScreenName
+    , combineWithScreenNumber
+    , WorkspaceScreenCombiner
+    -- * Limitations
+    -- $limitations
+    ) where
+
+import           Graphics.X11.Xrandr
+import           XMonad
+import           XMonad.Hooks.StatusBar.PP
+import           XMonad.Prelude
+import qualified XMonad.StackSet               as W
+
+{- $usage
+ You can use this module with the following in your @~\/.xmonad\/xmonad.hs@:
+
+ > import XMonad
+ > import XMonad.Hooks.StatusBar
+ > import XMonad.Hooks.StatusBar.PP
+ > import XMonad.Hooks.StatusBar.WorkspaceScreen
+
+ For example, to add the screen number in parentheses to each visible
+ workspace number, you can use 'combineWithScreenNumber':
+
+ > myWorkspaceScreenCombiner :: WorkspaceId -> String -> String
+ > myWorkspaceScreenCombiner w sc = w <> wrap "(" ")" sc
+ >
+ > mySB = statusBarProp "xmobar" (combineWithScreenNumber myWorkspaceScreenCombiner xmobarPP)
+ > main = xmonad $ withEasySB mySB defToggleStrutsKey def
+
+ This will annotate the workspace names as following:
+
+ > [1(0)] 2 3 4 <5(1)> 6 7 8 9
+
+ To use the screen's name instead, checkout 'combineWithScreenName':
+
+ > [1(eDP-1)] 2 3 4 <5(HDMI-1)> 6 7 8 9
+
+ For advanced cases, use 'combineWithScreen'.
+-}
+
+{- $limitations
+ For simplicity, this module assumes xmonad screen ids match screen/monitor
+ numbers as managed by the X server (for example, as given by @xrandr
+ --listactivemonitors@). Thus, it may not work well when screens show an
+ overlapping range of the framebuffer, e.g. when using a projector. This also
+ means that it doesn't work with "XMonad.Layout.LayoutScreens".
+ (This isn't difficult to fix, PRs welcome.)
+-}
+
+-- | Type synonym for a function that combines a workspace name with a screen.
+type WorkspaceScreenCombiner = WorkspaceId -> WindowScreen -> String
+
+-- | A helper function that returns a list of screen names.
+screenNames :: X [Maybe String]
+screenNames = do
+    XConf { display, theRoot } <- ask
+    let getName mi = getAtomName display (xrr_moninf_name mi)
+    io
+        $   maybe (pure []) (traverse getName)
+        =<< xrrGetMonitors display theRoot True
+
+-- | Combine a workspace name with the screen name it's visible on.
+combineWithScreenName :: (WorkspaceId -> String -> String) -> PP -> X PP
+combineWithScreenName c = combineWithScreen $ do
+    screens <- screenNames
+    return $ \w sc -> maybe w (c w) $ join (screens !? fi (W.screen sc))
+
+-- | Combine a workspace name with the screen number it's visible on.
+combineWithScreenNumber :: (WorkspaceId -> String -> String) -> PP -> X PP
+combineWithScreenNumber c =
+    combineWithScreen . return $ \w sc -> c w (show @Int . fi . W.screen $ sc)
+
+-- | Combine a workspace name with a screen according to the given
+-- 'WorkspaceScreenCombiner'.
+combineWithScreen :: X WorkspaceScreenCombiner -> PP -> X PP
+combineWithScreen xCombiner pp = do
+    combiner <- xCombiner
+    ss       <- withWindowSet (return . W.screens)
+    return $ pp
+        { ppRename = ppRename pp <=< \s w ->
+            maybe s (combiner s) (find ((== W.tag w) . W.tag . W.workspace) ss)
+        }

XMonad/Layout/IndependentScreens.hs

@@ -148,7 +148,7 @@ withWspOnScreen screenId operation ws = case workspaceOnScreen screenId ws of
     Nothing -> ws
 
 -- | Get the workspace that is active on a given screen.
-screenOnMonitor :: ScreenId -> WindowSet -> Maybe (W.Screen WorkspaceId (Layout Window) Window ScreenId ScreenDetail)
+screenOnMonitor :: ScreenId -> WindowSet -> Maybe WindowScreen
 screenOnMonitor screenId ws = find ((screenId ==) . W.screen) (W.current ws : W.visible ws)
 
 -- | Focus a window, switching workspace on the correct Xinerama screen if neccessary.

XMonad/Prelude.hs

@@ -32,6 +32,7 @@ module XMonad.Prelude (
     specialKeys,
     multimediaKeys,
     functionKeys,
+    WindowScreen,
 ) where
 
 import Foreign (alloca, peek)
@@ -57,6 +58,7 @@ import Data.Bits
 import Data.List.NonEmpty (NonEmpty ((:|)))
 import Data.Tuple (swap)
 import GHC.Stack
+import qualified XMonad.StackSet as W
 
 -- | Short for 'fromIntegral'.
 fi :: (Integral a, Num b) => a -> b
@@ -415,3 +417,7 @@ multimediaKeys = filter ((/= noSymbol) . snd) . map (id &&& stringToKeysym) $
   , "XF86_Prev_VMode"
   , "XF86Bluetooth"
   ]
+
+-- | The specialized 'W.Screen' derived from 'WindowSet'.
+type WindowScreen -- FIXME move to core
+    = W.Screen WorkspaceId (Layout Window) Window ScreenId ScreenDetail

XMonad/Util/Loggers.hs

@@ -48,7 +48,7 @@ module XMonad.Util.Loggers (
 
   ) where
 
-import XMonad (liftIO, Window, gets)
+import XMonad (liftIO, gets)
 import XMonad.Core
 import qualified XMonad.StackSet as W
 import XMonad.Hooks.StatusBar.PP
@@ -56,7 +56,7 @@ import XMonad.Util.Font (Align (..))
 import XMonad.Util.NamedWindows (getName)
 
 import Control.Exception as E
-import XMonad.Prelude (find, fromMaybe, isPrefixOf, isSuffixOf)
+import XMonad.Prelude (find, fromMaybe, isPrefixOf, isSuffixOf, WindowScreen)
 import Data.Time (defaultTimeLocale, formatTime, getCurrentTime)
 import System.Directory (getDirectoryContents)
 import System.IO (hGetLine)
@@ -272,9 +272,6 @@ logLayoutOnScreen :: ScreenId -> Logger
 logLayoutOnScreen =
   withScreen $ logConst . description . W.layout . W.workspace
 
--- | A shortcut to a screen
-type WindowScreen = W.Screen WorkspaceId (Layout Window) Window ScreenId ScreenDetail
-
 -- | A helper function to create screen-specific loggers.
 withScreen :: (WindowScreen -> Logger) -> ScreenId -> Logger
 withScreen f n = do

XMonad/Util/PureX.hs

@@ -53,7 +53,7 @@ module XMonad.Util.PureX (
 
 -- xmonad
 import XMonad
-import XMonad.Prelude (Any (..), liftA2)
+import XMonad.Prelude (Any (..), liftA2, WindowScreen)
 import qualified XMonad.StackSet as W
 import qualified XMonad.Actions.FocusNth
 
@@ -220,9 +220,7 @@ peek :: XLike m => m (Maybe Window)
 peek = withWindowSet' (return . W.peek)
 
 -- | Get the current screen.
-curScreen
+curScreen :: XLike m => m WindowScreen
-  :: XLike m
-  => m (W.Screen WorkspaceId (Layout Window) Window ScreenId ScreenDetail)
 curScreen = withWindowSet' (return . W.current)
 
 -- | Get the current workspace.

xmonad-contrib.cabal

@@ -200,6 +200,7 @@ library
                         XMonad.Hooks.SetWMName
                         XMonad.Hooks.StatusBar
                         XMonad.Hooks.StatusBar.PP
+                        XMonad.Hooks.StatusBar.WorkspaceScreen
                         XMonad.Hooks.TaffybarPagerHints
                         XMonad.Hooks.ToggleHook
                         XMonad.Hooks.UrgencyHook