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diff --git a/gtk+-mingw/share/gtk-doc/html/gobject/howto-signals.html b/gtk+-mingw/share/gtk-doc/html/gobject/howto-signals.html deleted file mode 100644 index 27ab1f7..0000000 --- a/gtk+-mingw/share/gtk-doc/html/gobject/howto-signals.html +++ /dev/null @@ -1,121 +0,0 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> -<html> -<head> -<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> -<title>How to create and use signals</title> -<meta name="generator" content="DocBook XSL Stylesheets V1.76.1"> -<link rel="home" href="index.html" title="GObject Reference Manual"> -<link rel="up" href="pt02.html" title="Part IV. Tutorial"> -<link rel="prev" href="howto-interface-override.html" title="Overriding interface methods"> -<link rel="next" href="pt03.html" title="Part V. Related Tools"> -<meta name="generator" content="GTK-Doc V1.18 (XML mode)"> -<link rel="stylesheet" href="style.css" type="text/css"> -</head> -<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> -<table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="2"><tr valign="middle"> -<td><a accesskey="p" href="howto-interface-override.html"><img src="left.png" width="24" height="24" border="0" alt="Prev"></a></td> -<td><a accesskey="u" href="pt02.html"><img src="up.png" width="24" height="24" border="0" alt="Up"></a></td> -<td><a accesskey="h" href="index.html"><img src="home.png" width="24" height="24" border="0" alt="Home"></a></td> -<th width="100%" align="center">GObject Reference Manual</th> -<td><a accesskey="n" href="pt03.html"><img src="right.png" width="24" height="24" border="0" alt="Next"></a></td> -</tr></table> -<div class="chapter"> -<div class="titlepage"><div><div><h2 class="title"> -<a name="howto-signals"></a>How to create and use signals</h2></div></div></div> -<div class="toc"><dl><dt><span class="sect1"><a href="howto-signals.html#howto-simple-signals">Simple use of signals</a></span></dt></dl></div> -<p> - The signal system which was built in GType is pretty complex and - flexible: it is possible for its users to connect at runtime any - number of callbacks (implemented in any language for which a binding - exists) - <sup>[<a name="idp21779776" href="#ftn.idp21779776" class="footnote">13</a>]</sup> - to any signal and to stop the emission of any signal at any - state of the signal emission process. This flexibility makes it - possible to use GSignal for much more than just emit signals which - can be received by numerous clients. - </p> -<div class="sect1"> -<div class="titlepage"><div><div><h2 class="title" style="clear: both"> -<a name="howto-simple-signals"></a>Simple use of signals</h2></div></div></div> -<p> - The most basic use of signals is to implement simple event - notification: for example, if we have a MamanFile object, and - if this object has a write method, we might wish to be notified - whenever someone has changed something via our MamanFile instance. - The code below shows how the user can connect a callback to the - "changed" signal. -</p> -<pre class="programlisting"> -file = g_object_new (MAMAN_FILE_TYPE, NULL); - -g_signal_connect (file, "changed", G_CALLBACK (changed_event), NULL); - -maman_file_write (file, buffer, strlen (buffer)); -</pre> -<p> - </p> -<p> - The <span class="type">MamanFile</span> signal is registered in the class_init - function: -</p> -<pre class="programlisting"> -file_signals[CHANGED] = - g_signal_newv ("changed", - G_TYPE_FROM_CLASS (gobject_class), - G_SIGNAL_RUN_LAST | G_SIGNAL_NO_RECURSE | G_SIGNAL_NO_HOOKS, - NULL /* closure */, - NULL /* accumulator */, - NULL /* accumulator data */, - g_cclosure_marshal_VOID__VOID, - G_TYPE_NONE /* return_type */, - 0 /* n_params */, - NULL /* param_types */); -</pre> -<p> - and the signal is emitted in <code class="function">maman_file_write</code>: -</p> -<pre class="programlisting"> -void -maman_file_write (MamanFile *self, - const guchar *buffer, - gssize size) -{ - /* First write data. */ - - /* Then, notify user of data written. */ - g_signal_emit (self, file_signals[CHANGED], 0 /* details */); -} -</pre> -<p> - As shown above, you can safely set the details parameter to zero if - you do not know what it can be used for. For a discussion of what you - could used it for, see <a class="xref" href="signal.html#signal-detail" title="The detail argument">the section called “The <span class="emphasis"><em>detail</em></span> argument”</a> - </p> -<p> - The signature of the signal handler in the above example is defined as - <code class="function">g_cclosure_marshal_VOID__VOID</code>. Its name follows - a simple convention which encodes the function parameter and return value - types in the function name. Specifically, the value in front of the - double underscore is the type of the return value, while the value(s) - after the double underscore denote the parameter types. - </p> -<p> - The header <code class="filename">gobject/gmarshal.h</code> defines a set of - commonly needed closures that one can use. If you want to have complex - marshallers for your signals you should probably use glib-genmarshal - to autogenerate them from a file containing their return and - parameter types. - </p> -</div> -<div class="footnotes"> -<br><hr width="100" align="left"> -<div class="footnote"><p><sup>[<a id="ftn.idp21779776" href="#idp21779776" class="para">13</a>] </sup>A Python callback can be connected to any signal on any - C-based GObject. - </p></div> -</div> -</div> -<div class="footer"> -<hr> - Generated by GTK-Doc V1.18</div> -</body> -</html>
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