gclosure.sgml

GLib是GTK+和GNOME工程的基础底层核心程序库

</entry></row>
<row><entry align="right"><parameter>n_param_values</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>param_values</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>invocation_hint</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>marshal_data</parameter>&nbsp;:</entry>
<entry>


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="GClosureNotify">GClosureNotify ()</title>
<programlisting>void        (*GClosureNotify)               (<link linkend="gpointer">gpointer</link> data,
                                             <link linkend="GClosure">GClosure</link> *closure);</programlisting>
<para>

</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>data</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>closure</parameter>&nbsp;:</entry>
<entry>


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="GClosureNotifyData">struct GClosureNotifyData</title>
<programlisting>struct GClosureNotifyData
{
  gpointer       data;
  GClosureNotify notify;
};
</programlisting>
<para>

</para></refsect2>
<refsect2>
<title><anchor id="g-cclosure-new">g_cclosure_new ()</title>
<programlisting><link linkend="GClosure">GClosure</link>*   g_cclosure_new                  (<link linkend="GCallback">GCallback</link> callback_func,
                                             <link linkend="gpointer">gpointer</link> user_data,
                                             <link linkend="GClosureNotify">GClosureNotify</link> destroy_data);</programlisting>
<para>

</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>callback_func</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>user_data</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>destroy_data</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry>


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-cclosure-new-swap">g_cclosure_new_swap ()</title>
<programlisting><link linkend="GClosure">GClosure</link>*   g_cclosure_new_swap             (<link linkend="GCallback">GCallback</link> callback_func,
                                             <link linkend="gpointer">gpointer</link> user_data,
                                             <link linkend="GClosureNotify">GClosureNotify</link> destroy_data);</programlisting>
<para>

</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>callback_func</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>user_data</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>destroy_data</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry>


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-cclosure-new-object">g_cclosure_new_object ()</title>
<programlisting><link linkend="GClosure">GClosure</link>*   g_cclosure_new_object           (<link linkend="GCallback">GCallback</link> callback_func,
                                             <link linkend="GObject">GObject</link> *object);</programlisting>
<para>

</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>callback_func</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>object</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry>


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-cclosure-new-object-swap">g_cclosure_new_object_swap ()</title>
<programlisting><link linkend="GClosure">GClosure</link>*   g_cclosure_new_object_swap      (<link linkend="GCallback">GCallback</link> callback_func,
                                             <link linkend="GObject">GObject</link> *object);</programlisting>
<para>

</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>callback_func</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>object</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry>


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-closure-new-object">g_closure_new_object ()</title>
<programlisting><link linkend="GClosure">GClosure</link>*   g_closure_new_object            (<link linkend="guint">guint</link> sizeof_closure,
                                             <link linkend="GObject">GObject</link> *object);</programlisting>
<para>

</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>sizeof_closure</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>object</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry>


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-closure-ref">g_closure_ref ()</title>
<programlisting><link linkend="GClosure">GClosure</link>*   g_closure_ref                   (<link linkend="GClosure">GClosure</link> *closure);</programlisting>
<para>
Increment the reference count on a closure to force it staying
alive while the caller holds a pointer to it.
</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
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<tbody>
<row><entry align="right"><parameter>closure</parameter>&nbsp;:</entry>
<entry><link linkend="GClosure">GClosure</link> to increment the reference count on
</entry></row>
<row><entry align="right"><emphasis>Returns</emphasis> :</entry><entry>The <parameter>closure</parameter> passed in, for convenience


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-closure-sink">g_closure_sink ()</title>
<programlisting>void        g_closure_sink                  (<link linkend="GClosure">GClosure</link> *closure);</programlisting>
<para>
Take over the initial ownership of a closure.
When closures are newly created, they get an initial reference count
of 1, eventhough no caller has yet invoked <link linkend="g-closure-ref">g_closure_ref</link>() on the <parameter>closure</parameter>.
Code entities that store closures for notification purposes are supposed
to call this function, for example like this:
<msgtext><programlisting>
static GClosure *notify_closure = NULL;
void
foo_notify_set_closure (GClosure *closure)
{
  if (notify_closure)
    g_closure_unref (notify_closure);
  notify_closure = closure;
  if (notify_closure)
    {
      g_closure_ref (notify_closure);
      g_closure_sink (notify_closure);
    }
}
</programlisting></msgtext>
Because <link linkend="g-closure-sink">g_closure_sink</link>() may decrement the reference count of a closure
(if it hasn't been called on <parameter>closure</parameter> yet) just like <link linkend="g-closure-unref">g_closure_unref</link>(),
<link linkend="g-closure-ref">g_closure_ref</link>() should be called prior to this function.
</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
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<tbody>
<row><entry align="right"><parameter>closure</parameter>&nbsp;:</entry>
<entry><link linkend="GClosure">GClosure</link> to decrement the initial reference count on, if it's
          still being held


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-closure-unref">g_closure_unref ()</title>
<programlisting>void        g_closure_unref                 (<link linkend="GClosure">GClosure</link> *closure);</programlisting>
<para>
Decrement the reference count of a closure after it was
previously incremented by the same caller. The closure
will most likely be destroyed and freed after this function
returns.
</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
<colspec colwidth="8*">
<tbody>
<row><entry align="right"><parameter>closure</parameter>&nbsp;:</entry>
<entry><link linkend="GClosure">GClosure</link> to decrement the reference count on


</entry></row>
</tbody></tgroup></informaltable></refsect2>
<refsect2>
<title><anchor id="g-closure-invoke">g_closure_invoke ()</title>
<programlisting>void        g_closure_invoke                (<link linkend="GClosure">GClosure</link> *closure,
                                             <link linkend="GValue">GValue</link> *return_value,
                                             <link linkend="guint">guint</link> n_param_values,
                                             const <link linkend="GValue">GValue</link> *param_values,
                                             <link linkend="gpointer">gpointer</link> invocation_hint);</programlisting>
<para>

</para><informaltable pgwide="1" frame="none" role="params">
<tgroup cols="2">
<colspec colwidth="2*">
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<tbody>
<row><entry align="right"><parameter>closure</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>return_value</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>n_param_values</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>param_values</parameter>&nbsp;:</entry>
<entry>
</entry></row>
<row><entry align="right"><parameter>invocation_hint</parameter>&nbsp;:</entry>
<entry>