<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Graphics.UI.Gtk.Windows.OffscreenWindow</title><link href="ocean.css" rel="stylesheet" type="text/css" title="Ocean" /><script src="haddock-util.js" type="text/javascript"></script><script type="text/javascript">//<![CDATA[
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</script></head><body><div id="package-header"><ul class="links" id="page-menu"><li><a href="src/Graphics-UI-Gtk-Windows-OffscreenWindow.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">gtk-0.12.0: Binding to the Gtk+ graphical user interface library.</p></div><div id="content"><div id="module-header"><table class="info"><tr><th>Portability</th><td>portable (depends on GHC)</td></tr><tr><th>Stability</th><td>provisional</td></tr><tr><th>Maintainer</th><td>gtk2hs-users@lists.sourceforge.net</td></tr></table><p class="caption">Graphics.UI.Gtk.Windows.OffscreenWindow</p></div><div id="table-of-contents"><p class="caption">Contents</p><ul><li><a href="#g:1">Detail
</a></li><li><a href="#g:2">Class Hierarchy
</a></li><li><a href="#g:3">Types
</a></li><li><a href="#g:4">Constructors
</a></li><li><a href="#g:5">Methods
</a></li></ul></div><div id="description"><p class="caption">Description</p><div class="doc"><p>A toplevel container widget used to manage offscreen rendering of child widgets.
</p><ul><li> Module available since Gtk+ version 2.20
</li></ul></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">data</span> <a href="#t:OffscreenWindow">OffscreenWindow</a> </li><li class="src short"><span class="keyword">class</span> <a href="Graphics-UI-Gtk-Windows-Window.html#t:WindowClass">WindowClass</a> o => <a href="#t:OffscreenWindowClass">OffscreenWindowClass</a> o </li><li class="src short"><a href="#v:castToOffscreenWindow">castToOffscreenWindow</a> :: <a href="/usr/share/doc/ghc/html/libraries/glib-0.12.0/System-Glib-GObject.html#t:GObjectClass">GObjectClass</a> obj => obj -> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></li><li class="src short"><a href="#v:gTypeOffscreenWindow">gTypeOffscreenWindow</a> :: <a href="Graphics-UI-Gtk-Abstract-Widget.html#t:GType">GType</a></li><li class="src short"><a href="#v:toOffscreenWindow">toOffscreenWindow</a> :: <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindowClass">OffscreenWindowClass</a> o => o -> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></li><li class="src short"><a href="#v:offscreenWindowNew">offscreenWindowNew</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></li><li class="src short"><a href="#v:offscreenWindowGetPixmap">offscreenWindowGetPixmap</a> :: <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindowClass">OffscreenWindowClass</a> self => self -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> <a href="Graphics-UI-Gtk-Gdk-Pixmap.html#t:Pixmap">Pixmap</a>)</li><li class="src short"><a href="#v:offscreenWindowGetPixbuf">offscreenWindowGetPixbuf</a> :: <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindowClass">OffscreenWindowClass</a> self => self -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> <a href="Graphics-UI-Gtk-Gdk-Pixbuf.html#t:Pixbuf">Pixbuf</a>)</li></ul></div><div id="interface"><h1 id="g:1">Detail
</h1><div class="doc"><p><code><a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></code> is strictly intended to be used for obtaining snapshots of widgets that are not
part of a normal widget hierarchy. It differs from <code>widgetGetSnapshot</code> in that the widget you
want to get a snapshot of need not be displayed on the user's screen as a part of a widget
hierarchy. However, since <code><a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></code> is a toplevel widget you cannot obtain snapshots of a
full window with it since you cannot pack a toplevel widget in another toplevel.
</p><p>The idea is to take a widget and manually set the state of it, add it to a <code><a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></code> and
then retrieve the snapshot as a <code><a href="Graphics-UI-Gtk-Gdk-Pixmap.html#t:Pixmap">Pixmap</a></code> or <code><a href="Graphics-UI-Gtk-Gdk-Pixbuf.html#t:Pixbuf">Pixbuf</a></code>.
</p><p><code><a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></code> derives from <code><a href="Graphics-UI-Gtk-Windows-Window.html#t:Window">Window</a></code> only as an implementation detail. Applications should not
use any API specific to <code><a href="Graphics-UI-Gtk-Windows-Window.html#t:Window">Window</a></code> to operate on this object. It should be treated as a <code><a href="Graphics-UI-Gtk-Abstract-Bin.html#t:Bin">Bin</a></code> that
has no parent widget.
</p><p>When contained offscreen widgets are redrawn, <code><a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></code> will emit a <code>damageEvent</code> signal.
</p></div><h1 id="g:2">Class Hierarchy
</h1><div class="doc"><pre>
| <code><a href="/usr/share/doc/ghc/html/libraries/glib-0.12.0/System-Glib-GObject.html#t:GObject">GObject</a></code>
| +----<code><a href="Graphics-UI-Gtk-Abstract-Object.html#t:Object">Object</a></code>
| +----<code><a href="Graphics-UI-Gtk-Abstract-Widget.html#t:Widget">Widget</a></code>
| +----<code><a href="Graphics-UI-Gtk-Abstract-Container.html#t:Container">Container</a></code>
| +----<code><a href="Graphics-UI-Gtk-Abstract-Bin.html#t:Bin">Bin</a></code>
| +----Window
| +----<code><a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></code>
</pre></div><h1 id="g:3">Types
</h1><div class="top"><p class="src"><span class="keyword">data</span> <a name="t:OffscreenWindow" class="def">OffscreenWindow</a> <a href="src/Graphics-UI-Gtk-Types.html#OffscreenWindow" class="link">Source</a></p><div class="subs instances"><p id="control.i:OffscreenWindow" class="caption collapser" onclick="toggleSection('i:OffscreenWindow')">Instances</p><div id="section.i:OffscreenWindow" class="show"><table><tr><td class="src"><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Eq.html#t:Eq">Eq</a> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</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/Data-Ord.html#t:Ord">Ord</a> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="/usr/share/doc/ghc/html/libraries/glib-0.12.0/System-Glib-GObject.html#t:GObjectClass">GObjectClass</a> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindowClass">OffscreenWindowClass</a> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Graphics-UI-Gtk-Windows-Window.html#t:WindowClass">WindowClass</a> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Graphics-UI-Gtk-Abstract-Bin.html#t:BinClass">BinClass</a> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Graphics-UI-Gtk-Abstract-Container.html#t:ContainerClass">ContainerClass</a> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Graphics-UI-Gtk-Abstract-Widget.html#t:WidgetClass">WidgetClass</a> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Graphics-UI-Gtk-Abstract-Object.html#t:ObjectClass">ObjectClass</a> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></td><td class="doc empty"> </td></tr></table></div></div></div><div class="top"><p class="src"><span class="keyword">class</span> <a href="Graphics-UI-Gtk-Windows-Window.html#t:WindowClass">WindowClass</a> o => <a name="t:OffscreenWindowClass" class="def">OffscreenWindowClass</a> o <a href="src/Graphics-UI-Gtk-Types.html#OffscreenWindowClass" class="link">Source</a></p><div class="subs instances"><p id="control.i:OffscreenWindowClass" class="caption collapser" onclick="toggleSection('i:OffscreenWindowClass')">Instances</p><div id="section.i:OffscreenWindowClass" class="show"><table><tr><td class="src"><a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindowClass">OffscreenWindowClass</a> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></td><td class="doc empty"> </td></tr></table></div></div></div><div class="top"><p class="src"><a name="v:castToOffscreenWindow" class="def">castToOffscreenWindow</a> :: <a href="/usr/share/doc/ghc/html/libraries/glib-0.12.0/System-Glib-GObject.html#t:GObjectClass">GObjectClass</a> obj => obj -> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a><a href="src/Graphics-UI-Gtk-Types.html#castToOffscreenWindow" class="link">Source</a></p></div><div class="top"><p class="src"><a name="v:gTypeOffscreenWindow" class="def">gTypeOffscreenWindow</a> :: <a href="Graphics-UI-Gtk-Abstract-Widget.html#t:GType">GType</a><a href="src/Graphics-UI-Gtk-Types.html#gTypeOffscreenWindow" class="link">Source</a></p></div><div class="top"><p class="src"><a name="v:toOffscreenWindow" class="def">toOffscreenWindow</a> :: <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindowClass">OffscreenWindowClass</a> o => o -> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a><a href="src/Graphics-UI-Gtk-Types.html#toOffscreenWindow" class="link">Source</a></p></div><h1 id="g:4">Constructors
</h1><div class="top"><p class="src"><a name="v:offscreenWindowNew" class="def">offscreenWindowNew</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a><a href="src/Graphics-UI-Gtk-Windows-OffscreenWindow.html#offscreenWindowNew" class="link">Source</a></p><div class="doc"><p>Creates a toplevel container widget that is used to retrieve snapshots of widgets without showing
them on the screen. For widgets that are on the screen and part of a normal widget hierarchy,
<code>widgetGetSnapshot</code> can be used instead.
</p><ul><li> Available since Gtk+ version 2.20
</li></ul></div></div><h1 id="g:5">Methods
</h1><div class="top"><p class="src"><a name="v:offscreenWindowGetPixmap" class="def">offscreenWindowGetPixmap</a><a href="src/Graphics-UI-Gtk-Windows-OffscreenWindow.html#offscreenWindowGetPixmap" class="link">Source</a></p><div class="subs arguments"><p class="caption">Arguments</p><table><tr><td class="src">:: <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindowClass">OffscreenWindowClass</a> self</td><td class="doc empty"> </td></tr><tr><td class="src">=> self</td><td class="doc"><p><code>offscreen</code> the <code><a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></code> contained widget.
</p></td></tr><tr><td class="src">-> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> <a href="Graphics-UI-Gtk-Gdk-Pixmap.html#t:Pixmap">Pixmap</a>)</td><td class="doc"><p>returns A <code><a href="Graphics-UI-Gtk-Gdk-Pixmap.html#t:Pixmap">Pixmap</a></code> pointer to the offscreen pixmap, or <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#v:Nothing">Nothing</a></code>.
</p></td></tr></table></div><div class="doc"><p>Retrieves a snapshot of the contained widget in the form of a <code><a href="Graphics-UI-Gtk-Gdk-Pixmap.html#t:Pixmap">Pixmap</a></code>. If you need to keep this
around over window resizes then you should add a reference to it.
</p><ul><li> Available since Gtk+ version 2.20
</li></ul></div></div><div class="top"><p class="src"><a name="v:offscreenWindowGetPixbuf" class="def">offscreenWindowGetPixbuf</a><a href="src/Graphics-UI-Gtk-Windows-OffscreenWindow.html#offscreenWindowGetPixbuf" class="link">Source</a></p><div class="subs arguments"><p class="caption">Arguments</p><table><tr><td class="src">:: <a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindowClass">OffscreenWindowClass</a> self</td><td class="doc empty"> </td></tr><tr><td class="src">=> self</td><td class="doc"><p><code>offscreen</code> the <code><a href="Graphics-UI-Gtk-Windows-OffscreenWindow.html#t:OffscreenWindow">OffscreenWindow</a></code> contained widget.
</p></td></tr><tr><td class="src">-> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#t:Maybe">Maybe</a> <a href="Graphics-UI-Gtk-Gdk-Pixbuf.html#t:Pixbuf">Pixbuf</a>)</td><td class="doc"><p>returns A <code><a href="Graphics-UI-Gtk-Gdk-Pixbuf.html#t:Pixbuf">Pixbuf</a></code> pointer to the offscreen pixbuf, or <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Maybe.html#v:Nothing">Nothing</a></code>.
</p></td></tr></table></div><div class="doc"><p>Retrieves a snapshot of the contained widget in the form of a <code><a href="Graphics-UI-Gtk-Gdk-Pixbuf.html#t:Pixbuf">Pixbuf</a></code>.
</p><ul><li> Available since Gtk+ version 2.20
</li></ul></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>
