xmonad-contrib-0.7: Third party extensions for xmonadContentsIndex
XMonad.Doc.Extending
Portabilityportable
Stabilityunstable
Maintainerandrea.rossato@unibz.it
Contents
The xmonad-contrib library
Actions
Configurations
Hooks
Layouts
Prompts
Utilities
Extending xmonad
Editing key bindings
Adding key bindings
Removing key bindings
Adding and removing key bindings
Editing mouse bindings
Editing the layout hook
Editing the manage hook
The log hook and external status bars
Description

This module documents the xmonad-contrib library and how to use it to extend the capabilities of xmonad.

Reading this document should not require a deep knowledge of Haskell; the examples are intended to be useful and understandable for those users who do not know Haskell and don't want to have to learn it just to configure xmonad. You should be able to get by just fine by ignoring anything you don't understand and using the provided examples as templates. However, relevant Haskell features are discussed when appropriate, so this document will hopefully be useful for more advanced Haskell users as well.

Those wishing to be totally hardcore and develop their own xmonad extensions (it's easier than it sounds, we promise!) should read the documentation in XMonad.Doc.Developing.

More configuration examples may be found on the Haskell wiki:

http://haskell.org/haskellwiki/Xmonad/Config_archive

Synopsis
The xmonad-contrib library

The xmonad-contrib (xmc) library is a set of extension modules contributed by xmonad hackers and users, which provide additional xmonad features. Examples include various layout modes (tabbed, spiral, three-column...), prompts, program launchers, the ability to manipulate windows and workspaces in various ways, alternate navigation modes, and much more. There are also "meta-modules" which make it easier to write new modules and extensions.

This is a concise yet complete overview of the xmonad-contrib modules. For more information about any particular module, just click on its name to view its Haddock documentation; each module should come with extensive documentation. If you find a module that could be better documented, or has incorrect documentation, please report it as a bug (http://code.google.com/p/xmonad/issues/list)!

Actions

In the XMonad.Actions namespace you can find modules exporting various functions that are usually intended to be bound to key combinations or mouse actions, in order to provide functionality beyond the standard keybindings provided by xmonad.

See XMonad.Doc.Extending#Editing_key_bindings for instructions on how to edit your key bindings.

Configurations

In the XMonad.Config namespace you can find modules exporting the configurations used by some of the xmonad and xmonad-contrib developers. You can look at them for examples while creating your own configuration; you can also simply import them and use them as your own configuration, possibly with some modifications.

Hooks

In the XMonad.Hooks namespace you can find modules exporting hooks. Hooks are actions that xmonad performs when certain events occur. The two most important hooks are:

  • manageHook: this hook is called when a new window xmonad must take care of is created. This is a very powerful hook, since it lets us examine the new window's properties and act accordingly. For instance, we can configure xmonad to put windows belonging to a given application in the float layer, not to manage dock applications, or open them in a given workspace. See XMonad.Doc.Extending#Editing_the_manage_hook for more information on customizing manageHook.
  • logHook: this hook is called when the stack of windows managed by xmonad has been changed, by calling the windows function. For instance XMonad.Hooks.DynamicLog will produce a string (whose format can be configured) to be printed to the standard output. This can be used to display some information about the xmonad state in a status bar. See XMonad.Doc.Extending#The_log_hook_and_external_status_bars for more information.

Here is a list of the modules found in XMonad.Hooks:

Layouts

In the XMonad.Layout namespace you can find modules exporting contributed tiling algorithms, such as a tabbed layout, a circle, a spiral, three columns, and so on.

You will also find modules which provide facilities for combining different layouts, such as XMonad.Layout.Combo, or XMonad.Layout.LayoutCombinators.

Layouts can be also modified with layout modifiers. A general interface for writing layout modifiers is implemented in XMonad.Layout.LayoutModifier.

For more information on using those modules for customizing your layoutHook see XMonad.Doc.Extending#Editing_the_layout_hook.

Prompts

In the XMonad.Prompt name space you can find modules providing graphical prompts for getting user input and using it to perform various actions.

The XMonad.Prompt provides a library for easily writing new prompt modules.

These are the available prompts:

Usually a prompt is called by some key binding. See XMonad.Doc.Extending#Editing_key_bindings, which includes examples of adding some prompts.

Utilities

In the XMonad.Util namespace you can find modules exporting various utility functions that are used by the other modules of the xmonad-contrib library.

There are also utilities for helping in configuring xmonad or using external utilities.

A non complete list with a brief description:

Extending xmonad

Since the xmonad.hs file is just another Haskell module, you may import and use any Haskell code or libraries you wish, such as extensions from the xmonad-contrib library, or other code you write yourself.

Editing key bindings

Editing key bindings means changing the keys field of the XConfig record used by xmonad. For example, you could write: 

    import XMonad

    main = xmonad $ defaultConfig { keys = myKeys }

and provide an appropriate definition of myKeys, such as: 

    myKeys x =
             [ ((modMask x, xK_F12), xmonadPrompt defaultXPConfig)
             , ((modMask x, xK_F3 ), shellPrompt  defaultXPConfig)
             ]

This particular definition also requires importing XMonad.Prompt, XMonad.Prompt.Shell, and XMonad.Prompt.XMonad: 

 import XMonadPrompt
 import ...  -- and so on

For a list of the names of particular keys (such as xK_F12, and so on), see http://hackage.haskell.org/packages/archive/X11/1.4.1/doc/html/Graphics-X11-Types.html.

Usually, rather than completely redefining the key bindings, as we did above, we want to simply add some new bindings and/or remove existing ones.

Adding key bindings

Adding key bindings can be done in different ways. The type signature of keys is: 

    keys :: XConfig Layout -> M.Map (ButtonMask,KeySym) (X ())

In order to add new key bindings, you need to first create an appropriate Map from a list of key bindings using fromList. This Map of new key bindings then needs to be joined to a Map of existing bindings using union.

Since we are going to need some of the functions of the Data.Map module, before starting we must first import this modules: 

    import qualified Data.Map as M

For instance, if you have defined some additional key bindings like these: 

    myKeys x =
             [ ((modMask x, xK_F12), xmonadPrompt defaultXPConfig)
             , ((modMask x, xK_F3 ), shellPrompt  defaultXPConfig)
             ]

then you can create a new key bindings map by joining the default one with yours: 

    newKeys x  = M.union (keys defaultConfig x) (M.fromList (myKeys x))

Finally, you can use newKeys in the keys field of the configuration: 

    main = xmonad $ defaultConfig { keys = newKeys }

All together, your ~/.xmonad/xmonad.hs would now look like this: 

    module Main (main) where

    import XMonad

    import qualified Data.Map as M
    import Graphics.X11.Xlib
    import XMonad.Prompt
    import XMonad.Prompt.Shell
    import XMonad.Prompt.XMonad

    main :: IO ()
    main = xmonad $ defaultConfig { keys = newKeys }

    newKeys x = M.union (keys defaultConfig x) (M.fromList (myKeys x))

    myKeys x =
             [ ((modMask x, xK_F12), xmonadPrompt defaultXPConfig)
             , ((modMask x, xK_F3 ), shellPrompt  defaultXPConfig)
             ]

There are much simpler ways to accomplish this, however, if you are willing to use an extension module to help you configure your keys. For instance, XMonad.Util.EZConfig and XMonad.Util.CustomKeys both provide useful functions for editing your key bindings; XMonad.Util.EZConfig even lets you use emacs-style keybinding descriptions like "M-C-F12".

Removing key bindings

Removing key bindings requires modifying the Map which stores the key bindings. This can be done with difference or with delete.

For example, suppose you want to get rid of mod-q and mod-shift-q (you just want to leave xmonad running forever). To do this you need to define newKeys as a difference between the default map and the map of the key bindings you want to remove. Like so: 

    newKeys x = M.difference (keys defaultConfig x) (M.fromList $ keysToRemove x)

    keysToRemove :: XConfig Layout ->    [((KeyMask, KeySym),X ())]
    keysToRemove x =
             [ ((modMask x              , xK_q ), return ())
             , ((modMask x .|. shiftMask, xK_q ), return ())
             ]

As you can see, it doesn't matter what actions we associate with the keys listed in keysToRemove, so we just use return () (the "null" action).

It is also possible to simply define a list of keys we want to unbind and then use delete to remove them. In that case we would write something like: 

    newKeys x = foldr M.delete (keys defaultConfig x) (keysToRemove x)

    keysToRemove :: XConfig Layout -> [(KeyMask, KeySym)]
    keysToRemove x =
             [ (modMask x              , xK_q )
             , (modMask x .|. shiftMask, xK_q )
             ]

Another even simpler possibility is the use of some of the utilities provided by the xmonad-contrib library. Look, for instance, at removeKeys.

Adding and removing key bindings

Adding and removing key bindings requires simply combining the steps for removing and adding. Here is an example from XMonad.Config.Arossato: 

    defKeys    = keys defaultConfig
    delKeys x  = foldr M.delete           (defKeys x) (toRemove x)
    newKeys x  = foldr (uncurry M.insert) (delKeys x) (toAdd    x)
    -- remove some of the default key bindings
    toRemove x =
        [ (modMask x              , xK_j     )
        , (modMask x              , xK_k     )
        , (modMask x              , xK_p     )
        , (modMask x .|. shiftMask, xK_p     )
        , (modMask x .|. shiftMask, xK_q     )
        , (modMask x              , xK_q     )
        ] ++
        -- I want modMask .|. shiftMask 1-9 to be free!
        [(shiftMask .|. modMask x, k) | k <- [xK_1 .. xK_9]]
    -- These are my personal key bindings
    toAdd x   =
        [ ((modMask x              , xK_F12   ), xmonadPrompt defaultXPConfig )
        , ((modMask x              , xK_F3    ), shellPrompt  defaultXPConfig )
        ] ++
        -- Use modMask .|. shiftMask .|. controlMask 1-9 instead
        [( (m .|. modMask x, k), windows $ f i)
         | (i, k) <- zip (workspaces x) [xK_1 .. xK_9]
        ,  (f, m) <- [(W.greedyView, 0), (W.shift, shiftMask .|. controlMask)]
        ]

You can achieve the same result using the XMonad.Util.CustomKeys module; take a look at the customKeys function in particular.

Editing mouse bindings

Most of the previous discussion of key bindings applies to mouse bindings as well. For example, you could configure button4 to close the window you click on like so: 

    import qualified Data.Map as M

    myMouse x  = [ (0, button4), (\w -> focus w >> kill) ]

    newMouse x = M.union (mouseBindings defaultConfig x) (M.fromList (myMouse x))

    main = xmonad $ defaultConfig { ..., mouseBindings = newMouse, ... }

Overriding or deleting mouse bindings works similarly. You can also configure mouse bindings much more easily using the additionalMouseBindings and removeMouseBindings functions from the XMonad.Util.EZConfig module.

Editing the layout hook

When you start an application that opens a new window, when you change the focused window, or move it to another workspace, or change that workspace's layout, xmonad will use the layoutHook for reordering the visible windows on the visible workspace(s).

Since different layouts may be attached to different workspaces, and you can change them, xmonad needs to know which one to use. In this sense the layoutHook may be thought as the list of layouts that xmonad will use for laying out windows on the screen(s).

The problem is that the layout subsystem is implemented with an advanced feature of the Haskell programming language: type classes. This allows us to very easily write new layouts, combine or modify existing layouts, create layouts with internal state, etc. See XMonad.Doc.Extending#The_LayoutClass for more information. This means that we cannot simply have a list of layouts as we used to have before the 0.5 release: a list requires every member to belong to the same type!

Instead the combination of layouts to be used by xmonad is created with a specific layout combinator: |||.

Suppose we want a list with the Full, tabbed and Accordion layouts. First we import, in our ~/.xmonad/xmonad.hs, all the needed modules: 

    import XMonad

    import XMonad.Layout.Tabbed
    import XMonad.Layout.Accordion

Then we create the combination of layouts we need: 

    mylayoutHook = Full ||| tabbed shrinkText defaultTConf ||| Accordion

Now, all we need to do is change the layoutHook field of the XConfig record, like so: 

    main = xmonad $ defaultConfig { layoutHook = mylayoutHook }

Thanks to the new combinator, we can apply a layout modifier to a whole combination of layouts, instead of applying it to each one. For example, suppose we want to use the noBorders layout modifier, from the XMonad.Layout.NoBorders module (which must be imported): 

    mylayoutHook = noBorders (Full ||| tabbed shrinkText defaultTConf ||| Accordion)

If we want only the tabbed layout without borders, then we may write: 

    mylayoutHook = Full ||| noBorders (tabbed shrinkText defaultTConf) ||| Accordion

Our ~/.xmonad/xmonad.hs will now look like this: 

    import XMonad

    import XMonad.Layout.Tabbed
    import XMonad.Layout.Accordion
    import XMonad.Layout.NoBorders

    mylayoutHook = Full ||| noBorders (tabbed shrinkText defaultTConf) ||| Accordion

    main = xmonad $ defaultConfig { layoutHook = mylayoutHook }

That's it!

Editing the manage hook

The manageHook is a very powerful tool for customizing the behavior of xmonad with regard to new windows. Whenever a new window is created, xmonad calls the manageHook, which can thus be used to perform certain actions on the new window, such as placing it in a specific workspace, ignoring it, or placing it in the float layer.

The default manageHook causes xmonad to float MPlayer and Gimp, and to ignore gnome-panel, desktop_window, kicker, and kdesktop.

The XMonad.ManageHook module provides some simple combinators that can be used to alter the manageHook by replacing or adding to the default actions.

Let's start by analyzing the default manageHook, defined in XMonad.Config: 

    manageHook :: ManageHook
    manageHook = composeAll
                    [ className =? "MPlayer"        --> doFloat
                    , className =? "Gimp"           --> doFloat
                    , resource  =? "desktop_window" --> doIgnore
                    , resource  =? "kdesktop"       --> doIgnore ]

composeAll can be used to compose a list of different ManageHooks. In this example we have a list of ManageHooks formed by the following commands: the Mplayer's and the Gimp's windows, whose className are, respectively "Mplayer" and "Gimp", are to be placed in the float layer with the doFloat function; the windows whose resource names are respectively "desktop_window" and kdesktop" are to be ignored with the doIgnore function.

This is another example of manageHook, taken from XMonad.Config.Arossato: 

    myManageHook  = composeAll [ resource =? "realplay.bin" --> doFloat
                               , resource =? "win"          --> doF (W.shift "doc") -- xpdf
                               , resource =? "firefox-bin"  --> doF (W.shift "web")
                               ]
    newManageHook = myManageHook <+> manageHook defaultConfig

Again we use composeAll to compose a list of different ManageHooks. The first one will put RealPlayer on the float layer, the second one will put the xpdf windows in the workspace named "doc", with doF and shift functions, and the third one will put all firefox windows on the workspace called web. Then we use the <+> combinator to compose myManageHook with the default manageHook to form newManageHook.

Each ManageHook has the form: 

    property =? match --> action

Where property can be:

(You can retrieve the needed information using the X utility named xprop; for example, to find the resource class name, you can type 

 xprop | grep WM_CLASS

at a prompt, then click on the window whose resource class you want to know.)

match is the string that will match the property value (for instance the one you retrieved with xprop).

An action can be:

  • doFloat: to place the window in the float layer;
  • doIgnore: to ignore the window;
  • doF: to execute a function with the window as argument.

For example, suppose we want to add a manageHook to float RealPlayer, which usually has a resource name of "realplay.bin".

First we need to import XMonad.ManageHook: 

    import XMonad.ManageHook

Then we create our own manageHook: 

    myManageHook = resource =? "realplay.bin" --> doFloat

We can now use the <+> combinator to add our manageHook to the default one: 

    newManageHook = myManageHook <+> manageHook defaultConfig

(Of course, if we wanted to completely replace the default manageHook, this step would not be necessary.) Now, all we need to do is change the manageHook field of the XConfig record, like so: 

    main = xmonad defaultConfig { ..., manageHook = newManageHook, ... }

And we are done.

Obviously, we may wish to add more then one manageHook. In this case we can use a list of hooks, compose them all with composeAll, and add the composed to the default one.

For instance, if we want RealPlayer to float and thunderbird always opened in the workspace named mail, we can do so like this: 

    myManageHook = composeAll [ resource =? "realplay.bin"    --> doFloat
                              , resource =? "thunderbird-bin" --> doF (W.shift "mail")
                              ]

Remember to import the module that defines the shift function, XMonad.StackSet, like this: 

    import qualified XMonad.StackSet as W

And then we can add myManageHook to the default one to create newManageHook as we did in the previous example.

One more thing to note about this system is that if a window matches multiple rules in a manageHook, all of the corresponding actions will be run (in the order in which they are defined). This is a change from versions before 0.5, when only the first rule that matched was run.

Finally, for additional rules and actions you can use in your manageHook, check out the contrib module XMonad.Hooks.ManageHelpers.

The log hook and external status bars

When the stack of the windows managed by xmonad changes for any reason, xmonad will call logHook, which can be used to output some information about the internal state of xmonad, such as the layout that is presently in use, the workspace we are in, the focused window's title, and so on.

Extracting information about the internal xmonad state can be somewhat difficult if you are not familiar with the source code. Therefore, it's usually easiest to use a module that has been designed specifically for logging some of the most interesting information about the internal state of xmonad: XMonad.Hooks.DynamicLog. This module can be used with an external status bar to print the produced logs in a convenient way; the most commonly used status bars are dzen and xmobar.

By default the logHook doesn't produce anything. To enable it you need first to import XMonad.Hooks.DynamicLog: 

    import XMonad.Hooks.DynamicLog

Then you just need to update the logHook field of the XConfig record with one of the provided functions. For example: 

    main = xmonad defaultConfig { logHook = dynamicLog }

More interesting configurations are also possible; see the XMonad.Hooks.DynamicLog module for more possibilities.

You may now enjoy your extended xmonad experience.

Have fun!

Produced by Haddock version 0.8