gtk.html

gtk是linux一款强大的夸平台的图形化开发工具

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<DT><U>Function:</U> gint <B>gtk_signal_connect</B> <I>(GtkObject *<VAR>object</VAR>, gchar *<VAR>name</VAR>, GtkSignalFunc <VAR>func</VAR>, gpointer <VAR>func_data</VAR>)</I>
<DD><A NAME="IDX52"></A>
Connects a signal handling function to a signal emitting
object. <VAR>func</VAR> is connected to the signal <VAR>name</VAR> emitted by
<VAR>object</VAR>. The arguments and returns type of <VAR>func</VAR> should match
the arguments and return type of the signal <VAR>name</VAR>. However,
<VAR>func</VAR> may take the extra argument of <VAR>func_data</VAR>. Due to the C
calling convention it is OK to ignore the extra argument. (It is OK to
ignore all the arguments in fact).

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<P>
<CODE>gtk_signal_connect</CODE> returns an integer identifier for the
connection which can be used to refer to it in the future. Specifically
it is useful for removing the connection and/or blocking it from being
used.
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<DT><U>Function:</U> gint <B>gtk_signal_connect_after</B> <I>(GtkObject *<VAR>object</VAR>, gchar *<VAR>name</VAR>, GtkSignalFunc <VAR>func</VAR>, gpointer <VAR>func_data</VAR>)</I>
<DD><A NAME="IDX53"></A>
Similar to <CODE>gtk_signal_connect</CODE> except the signal handler is
connected in the "after" slot. This allows a signal handler to be
guaranteed to run after other signal handlers connected to the same
signal on the same object and after the class function associated with
the signal.

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<P>
Like <CODE>gtk_signal_connect</CODE>, <CODE>gtk_signal_connect_after</CODE> returns
an integer identifier which can be used to refer to the connection.
</DL>

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<DT><U>Function:</U> gint <B>gtk_signal_connect_object</B> <I>(GtkObject *<VAR>object</VAR>, gchar *<VAR>name</VAR>, GtkSignalFunc <VAR>func</VAR>, GtkObject *<VAR>slot_object</VAR>)</I>
<DD><A NAME="IDX54"></A>
Connects <VAR>func</VAR> to the signal <VAR>name</VAR> emitted by
<VAR>object</VAR>. Similar to <CODE>gtk_signal_connect</CODE> with the difference
that <VAR>slot_object</VAR> is passed as the first parameter to <VAR>func</VAR>
instead of the signal emitting object. This can be useful for connecting
a signal emitted by one object to a signal in another object. A common
usage is to connect the "destroy" signal of dialog to the "clicked"
signal emitted by a "close" button in the dialog. That is, the
"clicked" signal emitted by the button will caused the "destroy"
signal to be emitted for the dialog. This is also the "right" way to
handle closing of a dialog since the "destroy" signal will be sent if
the dialog is deleted using a window manager function and this enables
the two methods of closing the window to be handled by the same
mechanism. Returns an integer identifier which can be used to refer to
the connection.
</DL>

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<DL>
<DT><U>Function:</U> gint <B>gtk_signal_connect_object_after</B> <I>(GtkObject *<VAR>object</VAR>, gchar *<VAR>name</VAR>, GtkSignalFunc <VAR>func</VAR>, GtkObject *<VAR>slot_object</VAR>)</I>
<DD><A NAME="IDX55"></A>
Similar to <CODE>gtk_signal_connect_object</CODE> except the signal handler is
connected in the "after" slot. This allows a signal handler to be
guaranteed to run after other signal handlers connected to the same
signal on the same object and after the class function associated with
the signal. Returns an integer identifier which can be used to refer to
the connection.
</DL>

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<DL>
<DT><U>Function:</U> gint <B>gtk_signal_connect_interp</B> <I>(GtkObject *<VAR>object</VAR>, gchar *<VAR>name</VAR>, GtkCallbackMarshal <VAR>func</VAR>, gpointer <VAR>data</VAR>, GtkDestroyNotify <VAR>destroy_func</VAR>, gint <VAR>after</VAR>)</I>
<DD><A NAME="IDX56"></A>
</DL>

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<DT><U>Function:</U> void <B>gtk_signal_disconnect</B> <I>(GtkObject *<VAR>object</VAR>, gint <VAR>id</VAR>)</I>
<DD><A NAME="IDX57"></A>
Disconnects a signal handler from an object. The signal handler is
identified by the integer <VAR>id</VAR> which is returned by the
<CODE>gtk_signal_connect*</CODE> family of functions.
</DL>

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<DT><U>Function:</U> void <B>gtk_signal_disconnect_by_data</B> <I>(GtkObject *<VAR>object</VAR>, gpointer <VAR>data</VAR>)</I>
<DD><A NAME="IDX58"></A>
Disconnects a signal handler from an object. The signal handler is
identified by the <VAR>data</VAR> argument specified as the <VAR>func_data</VAR>
argument to the <CODE>gtk_signal_connect*</CODE> family of functions. For the
<CODE>gtk_signal_connect_object*</CODE> functions, <VAR>data</VAR> refers to the
<VAR>slot_object</VAR>.

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<P>
<STRONG>Note:</STRONG> This will remove all signal handlers connected to
<VAR>object</VAR> which were connected using <VAR>data</VAR> as their
<VAR>func_data</VAR> argument. Multiple signal handlers may be disconnected
with this call.
</DL>

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<DL>
<DT><U>Function:</U> void <B>gtk_signal_handler_block</B> <I>(GtkObject *<VAR>object</VAR>, gint <VAR>id</VAR>)</I>
<DD><A NAME="IDX59"></A>
Blocks calling of a signal handler during signal emission. The signal
handler is identified by the integer <VAR>id</VAR> which is returned by the
<CODE>gtk_signal_connect*</CODE> family of functions. If the signal is already
blocked no change is made.
</DL>

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<DL>
<DT><U>Function:</U> void <B>gtk_signal_handler_block_by_data</B> <I>(GtkObject *<VAR>object</VAR>, gint <VAR>data</VAR>)</I>
<DD><A NAME="IDX60"></A>
Blocks calling of a signal handler during signal emission. The signal
handler is identified by the <VAR>data</VAR> argument specified as the
<VAR>func_data</VAR> argument to the <CODE>gtk_signal_connect*</CODE> family of
functions. For the <CODE>gtk_signal_connect_object*</CODE> functions,
<VAR>data</VAR> refers to the <VAR>slot_object</VAR>. If the signal is already
blocked no change is made.

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<P>
<STRONG>Note:</STRONG> This will block all signal handlers connected to
<VAR>object</VAR> which were connected using <VAR>data</VAR> as their
<VAR>func_data</VAR> argument. Multiple signal handlers may be blocked
with this call.
</DL>

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<DL>
<DT><U>Function:</U> void <B>gtk_signal_handler_unblock</B> <I>(GtkObject *<VAR>object</VAR>, gint <VAR>id</VAR>)</I>
<DD><A NAME="IDX61"></A>
Unblocks calling of a signal handler during signal emission. The signal
handler is identified by the integer <VAR>id</VAR> which is returned by the
<CODE>gtk_signal_connect*</CODE> family of functions. If the signal is already
unblocked no change is made.
</DL>

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<DL>
<DT><U>Function:</U> void <B>gtk_signal_handler_unblock_by_data</B> <I>(GtkObject *<VAR>object</VAR>, gint <VAR>data</VAR>)</I>
<DD><A NAME="IDX62"></A>
Unblocks calling of a signal handler during signal emission. The signal
handler is identified by the <VAR>data</VAR> argument specified as the
<VAR>func_data</VAR> argument to the <CODE>gtk_signal_connect*</CODE> family of
functions. For the <CODE>gtk_signal_connect_object*</CODE> functions,
<VAR>data</VAR> refers to the <VAR>slot_object</VAR>. If the signal is already
unblocked no change is made.

</P>
<P>
<STRONG>Note:</STRONG> This will unblock all signal handlers connected to
<VAR>object</VAR> which were connected using <VAR>data</VAR> as their
<VAR>func_data</VAR> argument. Multiple signal handlers may be unblocked
with this call.
</DL>

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<DL>
<DT><U>Function:</U> void <B>gtk_signal_handlers_destroy</B> <I>(GtkObject *<VAR>object</VAR>)</I>
<DD><A NAME="IDX63"></A>
Destroy all of the signal handlers connected to <VAR>object</VAR>. There
should normally never be reason to call this function as it is called
automatically when <VAR>object</VAR> is destroyed.
</DL>

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<DT><U>Function:</U> void <B>gtk_signal_default_marshaller</B> <I>(GtkObject *<VAR>object</VAR>, GtkSignalFunc <VAR>func</VAR>, gpointer <VAR>func_data</VAR>, GtkSignalParam *<VAR>params</VAR>)</I>
<DD><A NAME="IDX64"></A>
<CODE>gtk_signal_new</CODE> requires a callback in order to actually call a
signal handler for a particular signal. The vast majority of signals are
of the particular form:

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<PRE>
  (* std_signal) (gpointer std_arg);
</PRE>

<P>
<CODE>gtk_signal_default_marshaller</CODE> is a signal marshaller which
marshals arguments for a signal of that form.
</DL>

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<DT><U>Function:</U> void <B>gtk_signal_set_funcs</B> <I>(GtkSignalMarshal <VAR>marshal_func</VAR>, GtkSignalDestroy <VAR>destroy_fun</VAR>)</I>
<DD><A NAME="IDX65"></A>
</DL>

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<H1><A NAME="SEC15" HREF="gtk_toc.html#TOC15">Widget Overview</A></H1>
<P>
<A NAME="IDX66"></A>

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<P>
Widgets are the general term used to describe user interface objects. A
widget defines a class interface that all user interface objects conform
to. This interface allows a uniform method for dealing with operations
common to all objects such as hiding and showing, size requisition and
allocation and events.

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<P>
The common interface that widgets must adhere to is described by the
GtkWidget and GtkWidgetClass structure. For the purposes of using GTK
these structures can be considered read-only and, for the most part,
opaque.

</P>
<P>
All widget creation routines in GTK return pointers to GtkWidget
structures. In reality, all widget creation routines create structures
that can be viewed as equivalent to the GtkWidget structure, but often
have contain additional information. See section <A HREF="gtk.html#SEC414">Object internals</A>.

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<P>
The widgets available for use are implemented in a hierarchy. Several
widgets exist solely as common bases for more specific widgets. For
example, it is not possible to create a ruler widget itself, but the
ruler widget provides a base and functionality common to the horizontal
and vertical rulers.

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<P>
The available widgets (in alphabetical order):

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<H2><A NAME="SEC16" HREF="gtk_toc.html#TOC16">The alignment widget</A></H2>



<H3><A NAME="SEC17" HREF="gtk_toc.html#TOC17">Description</A></H3>

<P>
The alignment widget is a container (see section <A HREF="gtk.html#SEC75">The container widget</A>) derived from
the bin widget (see section <A HREF="gtk.html#SEC31">The bin widget</A>). Its entire purpose is to give the
programmer flexibility in how the child it manages is positioned when a
window is resized.

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<P>
Normally, a widget is allocated at least as much size as it
requests. (see section <A HREF="gtk.html#SEC75">The container widget</A> for a discussion of geometry
management). When a widget is allocated more size than it requests there
is a question of how the widget should expand. By convention, most GTK
widgets expand to fill their allocated space. Sometimes this behavior is
not desired. The alignment widget allows the programmer to specify how a
widget should expand and position itself to fill the area it is
allocated.

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<H3><A NAME="SEC18" HREF="gtk_toc.html#TOC18">Options</A></H3>

<P>
<DL>
<DT><U>User Option:</U> <B>xscale</B>
<DD><A NAME="IDX67"></A>
<DT><U>User Option:</U> <B>yscale</B>
<DD><A NAME="IDX68"></A>
The <VAR>xscale</VAR> and <VAR>yscale</VAR> options specify how to scale the child
widget. If the scale value is 0.0, the child widget is allocated exactly
the size it requested in that dimension. If the scale value is 1.0, the
child widget is allocated all of the space in a dimension. A scale value
of 1.0 for both x and y is equivalent to not using an alignment widget.
</DL>

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<DL>
<DT><U>User Option:</U> <B>xalign</B>
<DD><A NAME="IDX69"></A>
<DT><U>User Option:</U> <B>yalign</B>
<DD><A NAME="IDX70"></A>
The <VAR>xalign</VAR> and <VAR>yalign</VAR> options specify how to position the
child widget when it is not allocated all the space available to it
(because the <VAR>xscale</VAR> and/or <VAR>yscale</VAR> options are less than
1.0). If an alignment value is 0.0 the widget is positioned to the left
(or top) of its allocated space. An alignment value of 1.0 positions the
widget to the right (or bottom) of its allocated space. A common usage
is to specify <VAR>xalign</VAR> and <VAR>yalign</VAR> to be 0.5 which causes the
widget to be centered within its allocated area.
</DL>

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<H3><A NAME="SEC19" HREF="gtk_toc.html#TOC19">Signals</A></H3>



<H3><A NAME="SEC20" HREF="gtk_toc.html#TOC20">Functions</A></H3>

<P>
<DL>
<DT><U>Function:</U> guint <B>gtk_alignment_get_type</B> <I>(void)</I>
<DD><A NAME="IDX71"></A>
Returns the <CODE>GtkAlignment</CODE> type identifier.
</DL>

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<DL>
<DT><U>Function:</U> GtkWidget* <B>gtk_alignment_new</B> <I>(gfloat <VAR>xalign</VAR>, gfloat <VAR>yalign</VAR>, gfloat <VAR>xscale</VAR>, gfloat <VAR>yscale</VAR>)</I>
<DD><A NAME="IDX72"></A>
Create a new <CODE>GtkAlignment</CODE> object and initialize it with the
values <VAR>xalign</VAR>, <VAR>yalign</VAR>, <VAR>xscale</VAR> and <VAR>yscale</VAR>. The
new widget is returned as a pointer to a <CODE>GtkWidget</CODE>
object. <CODE>NULL</CODE> is returned on failure.
</DL>

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<DL>
<DT><U>Function:</U> void <B>gtk_alignment_set</B> <I>(GtkAlignment *<VAR>alignment</VAR>, gfloat <VAR>xalign</VAR>, gfloat <VAR>yalign</VAR>, gfloat <VAR>xscale</VAR>, gfloat <VAR>yscale</VAR>)</I>
<DD><A NAME="IDX73"></A>
Set the <VAR>xalign</VAR>, <VAR>yalign</VAR>, <VAR>xscale</VAR> and <VAR>yscale</VAR> options
of an alignment widget. It is important to not set the fields of the
<CODE>GtkAlignment</CODE> structure directly (or, for that matter, any type
derived from <CODE>GtkObject</CODE>).
</DL>

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<P>
@gtkstdmacros{Alignment, ALIGNMENT}

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<H2><A NAME="SEC21" HREF="gtk_toc.html#TOC21">The arrow widget</A></H2>



<H3><A NAME="SEC22" HREF="gtk_toc.html#TOC22">Description</A></H3>

<P>
The arrow widget is derived from the misc widget (see section <A HREF="gtk.html#SEC218">The misc widget</A>) and
is intended for use where a directional arrow (in one of the four
cardinal directions) is desired. As such, it has very limited
functionality and basically only draws itself in a particular direction
and with a particular shadow type. The arrow widget will expand to fill
all the space it is allocated.

</P>