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</script></head><body><div id="package-header"><ul class="links" id="page-menu"><li><a href="src/XMonad-Layout-LayoutModifier.html">Source</a></li><li><a href="index.html">Contents</a></li><li><a href="doc-index.html">Index</a></li></ul><p class="caption">xmonad-contrib-0.9.2: Third party extensions for xmonad</p></div><div id="content"><div id="module-header"><table class="info"><tr><th>Portability</th><td>portable</td></tr><tr><th>Stability</th><td>unstable</td></tr><tr><th>Maintainer</th><td>none</td></tr></table><p class="caption">XMonad.Layout.LayoutModifier</p></div><div id="table-of-contents"><p class="caption">Contents</p><ul><li><a href="#g:1">Usage
</a></li><li><a href="#g:2">The <code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code> class
</a></li></ul></div><div id="description"><p class="caption">Description</p><div class="doc"><p>A module for writing easy layout modifiers, which do not define a
layout in and of themselves, but modify the behavior of or add new
functionality to other layouts. If you ever find yourself writing
a layout which takes another layout as a parameter, chances are you
should be writing a LayoutModifier instead!
</p><p>In case it is not clear, this module is not intended to help you
configure xmonad, it is to help you write other extension modules.
So get hacking!
</p></div></div><div id="synopsis"><p id="control.syn" class="caption expander" onclick="toggleSection('syn')">Synopsis</p><ul id="section.syn" class="hide" onclick="toggleSection('syn')"><li class="src short"><span class="keyword">class</span> (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Show.html#t:Show">Show</a> (m a), <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Read.html#t:Read">Read</a> (m a)) => <a href="#t:LayoutModifier">LayoutModifier</a> m a <span class="keyword">where</span><ul class="subs"><li><a href="#v:modifyLayout">modifyLayout</a> :: LayoutClass l a => m a -> Workspace WorkspaceId (l a) a -> <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a> -> X ([(a, <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a>)], <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (l a))</li><li><a href="#v:handleMess">handleMess</a> :: m a -> SomeMessage -> X (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (m a))</li><li><a href="#v:handleMessOrMaybeModifyIt">handleMessOrMaybeModifyIt</a> :: m a -> SomeMessage -> X (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Either.html#t:Either">Either</a> (m a) SomeMessage))</li><li><a href="#v:pureMess">pureMess</a> :: m a -> SomeMessage -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (m a)</li><li><a href="#v:redoLayout">redoLayout</a> :: m a -> <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (Stack a) -> [(a, <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a>)] -> X ([(a, <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a>)], <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (m a))</li><li><a href="#v:pureModifier">pureModifier</a> :: m a -> <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (Stack a) -> [(a, <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a>)] -> ([(a, <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a>)], <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (m a))</li><li><a href="#v:hook">hook</a> :: m a -> X <a href="/usr/share/doc/ghc/html/libraries/ghc-prim-0.2.0.0/GHC-Unit.html#t:-40--41-">()</a></li><li><a href="#v:unhook">unhook</a> :: m a -> X <a href="/usr/share/doc/ghc/html/libraries/ghc-prim-0.2.0.0/GHC-Unit.html#t:-40--41-">()</a></li><li><a href="#v:modifierDescription">modifierDescription</a> :: m a -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Char.html#t:String">String</a></li><li><a href="#v:modifyDescription">modifyDescription</a> :: LayoutClass l a => m a -> l a -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Char.html#t:String">String</a></li></ul></li><li class="src short"><span class="keyword">data</span> <a href="#t:ModifiedLayout">ModifiedLayout</a> m l a = <a href="#v:ModifiedLayout">ModifiedLayout</a> (m a) (l a)</li></ul></div><div id="interface"><h1 id="g:1">Usage
</h1><div class="doc"><p>The <code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code> class is provided to help extension developers
write easy layout modifiers. End users won't find much of interest
here. =)
</p><p>To write a layout modifier using the <code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code> class, define
a data type to represent the layout modification (storing any
necessary state), define an instance of <code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code>, and
export an appropriate function for applying the modifier. For example:
</p><pre> data MyModifier a = MyModifier MyState
deriving (Show, Read)
instance LayoutModifier MyModifier a where
-- override whatever methods from LayoutModifier you like
modify :: l a -> ModifiedLayout MyModifier l a
modify = ModifiedLayout (MyModifier initialState)
</pre><p>When defining an instance of <code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code>, you are free to
override as many or as few of the methods as you see fit. See the
documentation below for specific information about the effect of
overriding each method. Every method has a default implementation;
an instance of <code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code> which did not provide a non-default
implementation of any of the methods would simply act as the
identity on any layouts to which it is applied.
</p><p>For more specific usage examples, see
</p><ul><li> <a href="XMonad-Layout-WorkspaceDir.html">XMonad.Layout.WorkspaceDir</a>
</li><li> <a href="XMonad-Layout-Magnifier.html">XMonad.Layout.Magnifier</a>
</li><li> <a href="XMonad-Layout-NoBorders.html">XMonad.Layout.NoBorders</a>
</li><li> <a href="XMonad-Layout-Reflect.html">XMonad.Layout.Reflect</a>
</li><li> <a href="XMonad-Layout-Named.html">XMonad.Layout.Named</a>
</li><li> <a href="XMonad-Layout-WindowNavigation.html">XMonad.Layout.WindowNavigation</a>
</li></ul><p>and several others. You probably want to start by looking at some
of the above examples; the documentation below is detailed but
possibly confusing, and in many cases the creation of a
<code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code> is actually quite simple.
</p><p><em>Important note</em>: because of the way the <code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code> class is
intended to be used, by overriding any of its methods and keeping
default implementations for all the others, <code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code>
methods should never be called explicitly. It is likely that such
explicit calls will not have the intended effect. Rather, the
<code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code> methods should only be called indirectly through
the <code>LayoutClass</code> instance for <code><a href="XMonad-Layout-LayoutModifier.html#t:ModifiedLayout">ModifiedLayout</a></code>, since it is this
instance that defines the semantics of overriding the various
<code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code> methods.
</p></div><h1 id="g:2">The <code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code> class
</h1><div class="top"><p class="src"><span class="keyword">class</span> (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Show.html#t:Show">Show</a> (m a), <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Read.html#t:Read">Read</a> (m a)) => <a name="t:LayoutModifier" class="def">LayoutModifier</a> m a <span class="keyword">where</span><a href="src/XMonad-Layout-LayoutModifier.html#LayoutModifier" class="link">Source</a></p><div class="subs methods"><p class="caption">Methods</p><p class="src"><a name="v:modifyLayout" class="def">modifyLayout</a><a href="src/XMonad-Layout-LayoutModifier.html#modifyLayout" class="link">Source</a></p><div class="subs arguments"><p class="caption">Arguments</p><table><tr><td class="src">:: LayoutClass l a</td><td class="doc empty"> </td></tr><tr><td class="src">=> m a</td><td class="doc"><p>the layout modifier
</p></td></tr><tr><td class="src">-> Workspace WorkspaceId (l a) a</td><td class="doc"><p>current workspace
</p></td></tr><tr><td class="src">-> <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a></td><td class="doc"><p>screen rectangle
</p></td></tr><tr><td class="src">-> X ([(a, <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a>)], <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (l a))</td><td class="doc empty"> </td></tr></table></div><div class="doc"><p><code><a href="XMonad-Layout-LayoutModifier.html#v:modifyLayout">modifyLayout</a></code> allows you to intercept a call to <code>runLayout</code>
<em>before</em> it is called on the underlying layout, in order to
perform some effect in the X monad, and/or modify some of
the parameters before passing them on to the <code>runLayout</code>
method of the underlying layout.
</p><p>The default implementation of <code><a href="XMonad-Layout-LayoutModifier.html#v:modifyLayout">modifyLayout</a></code> simply calls
<code>runLayout</code> on the underlying layout.
</p></div><p class="src"><a name="v:handleMess" class="def">handleMess</a> :: m a -> SomeMessage -> X (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (m a))<a href="src/XMonad-Layout-LayoutModifier.html#handleMess" class="link">Source</a></p><div class="doc"><p><code><a href="XMonad-Layout-LayoutModifier.html#v:handleMess">handleMess</a></code> allows you to spy on messages to the underlying
layout, in order to have an effect in the X monad, or alter
the layout modifier state in some way (by returning <code>Just
nm</code>, where <code>nm</code> is a new modifier). In all cases, the
underlying layout will also receive the message as usual,
after the message has been processed by <code><a href="XMonad-Layout-LayoutModifier.html#v:handleMess">handleMess</a></code>.
</p><p>If you wish to possibly modify a message before it reaches
the underlying layout, you should use
<code><a href="XMonad-Layout-LayoutModifier.html#v:handleMessOrMaybeModifyIt">handleMessOrMaybeModifyIt</a></code> instead. If you do not need to
modify messages or have access to the X monad, you should use
<code><a href="XMonad-Layout-LayoutModifier.html#v:pureMess">pureMess</a></code> instead.
</p><p>The default implementation of <code><a href="XMonad-Layout-LayoutModifier.html#v:handleMess">handleMess</a></code> calls <code><a href="XMonad-Layout-LayoutModifier.html#v:unhook">unhook</a></code>
when receiving a <code>Hide</code> or <code>ReleaseResources</code> method (after
which it returns <code>Nothing</code>), and otherwise passes the message
on to <code><a href="XMonad-Layout-LayoutModifier.html#v:pureMess">pureMess</a></code>.
</p></div><p class="src"><a name="v:handleMessOrMaybeModifyIt" class="def">handleMessOrMaybeModifyIt</a> :: m a -> SomeMessage -> X (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Either.html#t:Either">Either</a> (m a) SomeMessage))<a href="src/XMonad-Layout-LayoutModifier.html#handleMessOrMaybeModifyIt" class="link">Source</a></p><div class="doc"><p><code><a href="XMonad-Layout-LayoutModifier.html#v:handleMessOrMaybeModifyIt">handleMessOrMaybeModifyIt</a></code> allows you to intercept messages
sent to the underlying layout, in order to have an effect in
the X monad, alter the layout modifier state, or produce a
modified message to be passed on to the underlying layout.
</p><p>The default implementation of <code><a href="XMonad-Layout-LayoutModifier.html#v:handleMessOrMaybeModifyIt">handleMessOrMaybeModifyIt</a></code>
simply passes on the message to <code><a href="XMonad-Layout-LayoutModifier.html#v:handleMess">handleMess</a></code>.
</p></div><p class="src"><a name="v:pureMess" class="def">pureMess</a> :: m a -> SomeMessage -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (m a)<a href="src/XMonad-Layout-LayoutModifier.html#pureMess" class="link">Source</a></p><div class="doc"><p><code><a href="XMonad-Layout-LayoutModifier.html#v:pureMess">pureMess</a></code> allows you to spy on messages sent to the
underlying layout, in order to possibly change the layout
modifier state.
</p><p>The default implementation of <code><a href="XMonad-Layout-LayoutModifier.html#v:pureMess">pureMess</a></code> ignores messages
sent to it, and returns <code>Nothing</code> (causing the layout
modifier to remain unchanged).
</p></div><p class="src"><a name="v:redoLayout" class="def">redoLayout</a><a href="src/XMonad-Layout-LayoutModifier.html#redoLayout" class="link">Source</a></p><div class="subs arguments"><p class="caption">Arguments</p><table><tr><td class="src">:: m a</td><td class="doc"><p>the layout modifier
</p></td></tr><tr><td class="src">-> <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a></td><td class="doc"><p>screen rectangle
</p></td></tr><tr><td class="src">-> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (Stack a)</td><td class="doc"><p>current window stack
</p></td></tr><tr><td class="src">-> [(a, <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a>)]</td><td class="doc"><p>(window,rectangle) pairs returned
by the underlying layout
</p></td></tr><tr><td class="src">-> X ([(a, <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a>)], <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (m a))</td><td class="doc empty"> </td></tr></table></div><div class="doc"><p><code><a href="XMonad-Layout-LayoutModifier.html#v:redoLayout">redoLayout</a></code> allows you to intercept a call to <code>runLayout</code> on
workspaces with at least one window, <em>after</em> it is called on
the underlying layout, in order to perform some effect in the
X monad, possibly return a new layout modifier, and/or
modify the results of <code>runLayout</code> before returning them.
</p><p>If you don't need access to the X monad, use <code><a href="XMonad-Layout-LayoutModifier.html#v:pureModifier">pureModifier</a></code>
instead. Also, if the behavior you need can be cleanly
separated into an effect in the X monad, followed by a pure
transformation of the results of <code>runLayout</code>, you should
consider implementing <code><a href="XMonad-Layout-LayoutModifier.html#v:hook">hook</a></code> and <code><a href="XMonad-Layout-LayoutModifier.html#v:pureModifier">pureModifier</a></code> instead of
<code><a href="XMonad-Layout-LayoutModifier.html#v:redoLayout">redoLayout</a></code>.
</p><p>On empty workspaces, the Stack is Nothing.
</p><p>The default implementation of <code><a href="XMonad-Layout-LayoutModifier.html#v:redoLayout">redoLayout</a></code> calls <code><a href="XMonad-Layout-LayoutModifier.html#v:hook">hook</a></code> and
then <code><a href="XMonad-Layout-LayoutModifier.html#v:pureModifier">pureModifier</a></code>.
</p></div><p class="src"><a name="v:pureModifier" class="def">pureModifier</a><a href="src/XMonad-Layout-LayoutModifier.html#pureModifier" class="link">Source</a></p><div class="subs arguments"><p class="caption">Arguments</p><table><tr><td class="src">:: m a</td><td class="doc"><p>the layout modifier
</p></td></tr><tr><td class="src">-> <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a></td><td class="doc"><p>screen rectangle
</p></td></tr><tr><td class="src">-> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (Stack a)</td><td class="doc"><p>current window stack
</p></td></tr><tr><td class="src">-> [(a, <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a>)]</td><td class="doc"><p>(window, rectangle) pairs returned
by the underlying layout
</p></td></tr><tr><td class="src">-> ([(a, <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a>)], <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> (m a))</td><td class="doc empty"> </td></tr></table></div><div class="doc"><p><code><a href="XMonad-Layout-LayoutModifier.html#v:pureModifier">pureModifier</a></code> allows you to intercept a call to <code>runLayout</code>
<em>after</em> it is called on the underlying layout, in order to
modify the list of window/rectangle pairings it has returned,
and/or return a new layout modifier.
</p><p>The default implementation of <code><a href="XMonad-Layout-LayoutModifier.html#v:pureModifier">pureModifier</a></code> returns the
window rectangles unmodified.
</p></div><p class="src"><a name="v:hook" class="def">hook</a> :: m a -> X <a href="/usr/share/doc/ghc/html/libraries/ghc-prim-0.2.0.0/GHC-Unit.html#t:-40--41-">()</a><a href="src/XMonad-Layout-LayoutModifier.html#hook" class="link">Source</a></p><div class="doc"><p><code><a href="XMonad-Layout-LayoutModifier.html#v:hook">hook</a></code> is called by the default implementation of
<code><a href="XMonad-Layout-LayoutModifier.html#v:redoLayout">redoLayout</a></code>, and as such represents an X action which is to
be run each time <code>runLayout</code> is called on the underlying
layout, <em>after</em> <code>runLayout</code> has completed. Of course, if you
override <code><a href="XMonad-Layout-LayoutModifier.html#v:redoLayout">redoLayout</a></code>, then <code><a href="XMonad-Layout-LayoutModifier.html#v:hook">hook</a></code> will not be called unless
you explicitly call it.
</p><p>The default implementation of <code><a href="XMonad-Layout-LayoutModifier.html#v:hook">hook</a></code> is <code>return ()</code> (i.e., it
has no effect).
</p></div><p class="src"><a name="v:unhook" class="def">unhook</a> :: m a -> X <a href="/usr/share/doc/ghc/html/libraries/ghc-prim-0.2.0.0/GHC-Unit.html#t:-40--41-">()</a><a href="src/XMonad-Layout-LayoutModifier.html#unhook" class="link">Source</a></p><div class="doc"><p><code><a href="XMonad-Layout-LayoutModifier.html#v:unhook">unhook</a></code> is called by the default implementation of
<code><a href="XMonad-Layout-LayoutModifier.html#v:handleMess">handleMess</a></code> upon receiving a <code>Hide</code> or a <code>ReleaseResources</code>
message.
</p><p>The default implementation, of course, does nothing.
</p></div><p class="src"><a name="v:modifierDescription" class="def">modifierDescription</a> :: m a -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Char.html#t:String">String</a><a href="src/XMonad-Layout-LayoutModifier.html#modifierDescription" class="link">Source</a></p><div class="doc"><p><code><a href="XMonad-Layout-LayoutModifier.html#v:modifierDescription">modifierDescription</a></code> is used to give a String description to
this layout modifier. It is the empty string by default; you
should only override this if it is important that the
presence of the layout modifier be displayed in text
representations of the layout (for example, in the status bar
of a <a href="XMonad-Hooks-DynamicLog.html">XMonad.Hooks.DynamicLog</a> user).
</p></div><p class="src"><a name="v:modifyDescription" class="def">modifyDescription</a> :: LayoutClass l a => m a -> l a -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Char.html#t:String">String</a><a href="src/XMonad-Layout-LayoutModifier.html#modifyDescription" class="link">Source</a></p><div class="doc"><p><code><a href="XMonad-Layout-LayoutModifier.html#v:modifyDescription">modifyDescription</a></code> gives a String description for the entire
layout (modifier + underlying layout). By default, it is
derived from the concatenation of the <code><a href="XMonad-Layout-LayoutModifier.html#v:modifierDescription">modifierDescription</a></code>
with the <code>description</code> of the underlying layout, with a
"smart space" in between (the space is not included if the
<code><a href="XMonad-Layout-LayoutModifier.html#v:modifierDescription">modifierDescription</a></code> is empty).
</p></div></div><div class="subs instances"><p id="control.i:LayoutModifier" class="caption collapser" onclick="toggleSection('i:LayoutModifier')">Instances</p><div id="section.i:LayoutModifier" class="show"><table><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> Maximize <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> Magnifier <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> WithBorder <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> NameTail a</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> Named a</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> <a href="XMonad-Layout-BoringWindows.html#t:BoringWindows">BoringWindows</a> <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> Minimize <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> AutoMaster <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> TopRightMaster <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> CenteredMaster <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> AddRoster <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> Selection a</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> LimitWindows a</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> MagicFocus <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> AddMaster <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> <a href="XMonad-Layout-MessageControl.html#t:UnEscape">UnEscape</a> a</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> <a href="XMonad-Layout-Monitor.html#t:Monitor">Monitor</a> <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> Reflect a</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> Spacing a</td><td class="doc empty"> </td></tr><tr><td class="src">(<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Show.html#t:Show">Show</a> a, <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Read.html#t:Read">Read</a> a, <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Eq.html#t:Eq">Eq</a> a) => <a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> <a href="XMonad-Layout-WindowArranger.html#t:WindowArranger">WindowArranger</a> a</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> <a href="XMonad-Layout-ResizeScreen.html#t:ResizeScreen">ResizeScreen</a> a</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> <a href="XMonad-Actions-MouseResize.html#t:MouseResize">MouseResize</a> <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> <a href="XMonad-Layout-BorderResize.html#t:BorderResize">BorderResize</a> <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> ShowWName a</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> <a href="XMonad-Actions-WorkspaceCursors.html#t:WorkspaceCursors">WorkspaceCursors</a> a</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> WorkspaceDir <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> <a href="XMonad-Hooks-ManageDocks.html#t:AvoidStruts">AvoidStruts</a> a</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> WindowNavigation <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> Gaps a</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> LayoutHintsToCenter <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> <a href="XMonad-Layout-LayoutHints.html#t:LayoutHints">LayoutHints</a> <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src">(<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Read.html#t:Read">Read</a> p, <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Show.html#t:Show">Show</a> p, <a href="XMonad-Layout-NoBorders.html#t:SetsAmbiguous">SetsAmbiguous</a> p) => <a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> (ConfigurableBorder p) <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src">(<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Read.html#t:Read">Read</a> (l <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a>), <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Show.html#t:Show">Show</a> (l <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a>), LayoutClass l <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a>) => <a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> (Sublayout l) <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc empty"> </td></tr><tr><td class="src">(<a href="XMonad-Layout-Decoration.html#t:DecorationStyle">DecorationStyle</a> ds <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a>, <a href="XMonad-Layout-Decoration.html#t:Shrinker">Shrinker</a> s) => <a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> (<a href="XMonad-Layout-Decoration.html#t:Decoration">Decoration</a> ds s) <a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Types.html#t:Window">Window</a></td><td class="doc"><p>The long <code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code> instance for the <code><a href="XMonad-Layout-Decoration.html#t:Decoration">Decoration</a></code> type.
</p><p>In <code><a href="XMonad-Layout-LayoutModifier.html#v:redoLayout">redoLayout</a></code> we check the state: if there is no state we
initialize it.
</p><p>The state is <code><a href="XMonad-Layout-WindowArranger.html#v:diff">diff</a></code>ed against the list of windows produced by the
underlying layout: removed windows get deleted and new ones
decorated by <code>createDecos</code>, which will call <code><a href="XMonad-Layout-Decoration.html#v:decorate">decorate</a></code> to decide if
a window must be given a <code><a href="/usr/share/doc/ghc/html/libraries/X11-1.5.0.0/Graphics-X11-Xlib.html#t:Rectangle">Rectangle</a></code>, in which case a decoration
window will be created.
</p><p>After that we resync the updated state with the windows' list and
then we process the resynced stated (as we do with a new state).
</p><p>First we map the decoration windows, we update each decoration to
reflect any decorated window's change, and we insert, in the list
of windows and rectangles returned by the underlying layout, the
decoration for each window. This way xmonad will restack the
decorations and their windows accordingly. At the end we remove
invisible/stacked windows.
</p><p>Message handling is quite simple: when needed we release the state
component of the <code><a href="XMonad-Layout-Decoration.html#t:Decoration">Decoration</a></code> <code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code>. Otherwise we call
<code>handleEvent</code>, which will call the appropriate <code><a href="XMonad-Layout-Decoration.html#t:DecorationStyle">DecorationStyle</a></code>
methods to perform its tasks.
</p></td></tr></table></div></div></div><div class="top"><p class="src"><span class="keyword">data</span> <a name="t:ModifiedLayout" class="def">ModifiedLayout</a> m l a <a href="src/XMonad-Layout-LayoutModifier.html#ModifiedLayout" class="link">Source</a></p><div class="doc"><p>A <code><a href="XMonad-Layout-LayoutModifier.html#t:ModifiedLayout">ModifiedLayout</a></code> is simply a container for a layout modifier
combined with an underlying layout. It is, of course, itself a
layout (i.e. an instance of <code>LayoutClass</code>).
</p></div><div class="subs constructors"><p class="caption">Constructors</p><table><tr><td class="src"><a name="v:ModifiedLayout" class="def">ModifiedLayout</a> (m a) (l a)</td><td class="doc empty"> </td></tr></table></div><div class="subs instances"><p id="control.i:ModifiedLayout" class="caption collapser" onclick="toggleSection('i:ModifiedLayout')">Instances</p><div id="section.i:ModifiedLayout" class="show"><table><tr><td class="src">(<a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a> m a, LayoutClass l a) => LayoutClass (<a href="XMonad-Layout-LayoutModifier.html#t:ModifiedLayout">ModifiedLayout</a> m l) a</td><td class="doc"><p>The <code>LayoutClass</code> instance for a <code><a href="XMonad-Layout-LayoutModifier.html#t:ModifiedLayout">ModifiedLayout</a></code> defines the
semantics of a <code><a href="XMonad-Layout-LayoutModifier.html#t:LayoutModifier">LayoutModifier</a></code> applied to an underlying layout.
</p></td></tr><tr><td class="src">(<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Read.html#t:Read">Read</a> (m a), <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Read.html#t:Read">Read</a> (l a)) => <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Read.html#t:Read">Read</a> (<a href="XMonad-Layout-LayoutModifier.html#t:ModifiedLayout">ModifiedLayout</a> m l a)</td><td class="doc empty"> </td></tr><tr><td class="src">(<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Show.html#t:Show">Show</a> (m a), <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Show.html#t:Show">Show</a> (l a)) => <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Text-Show.html#t:Show">Show</a> (<a href="XMonad-Layout-LayoutModifier.html#t:ModifiedLayout">ModifiedLayout</a> m l a)</td><td class="doc empty"> </td></tr></table></div></div></div></div></div><div id="footer"><p>Produced by <a href="http://www.haskell.org/haddock/">Haddock</a> version 2.9.2</p></div></body></html>
