gtk2/gtk/gtkscrollable.c
2010-10-22 16:54:45 +02:00

328 lines
9.2 KiB
C

/* gtkscrollable.c
* Copyright (C) 2008 Tadej Borovšak <tadeboro@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:gtkscrollable
* @Short_Description: An interface for scrollable widgets
* @Title: GtkScrollable
*
* #GtkScrollable is interface that is implemented by widgets with native
* scrolling ability.
*
* To implement this interface, all one needs to do is to override
* #GtkScrollable:hadjustment and #GtkScrollable:vadjustment properties.
*
* <refsect2>
* <title>Creating a scrollable widget</title>
* <para>
* There are some common things all scrollable widgets will need to do.
*
* <orderedlist>
* <listitem>
* <para>
* When parent sets adjustments, widget needs to populate adjustment's
* #GtkAdjustment:lower, #GtkAdjustment:upper,
* #GtkAdjustment:step-increment, #GtkAdjustment:page-increment and
* #GtkAdjustment:page-size properties and connect to
* #GtkAdjustment::value-changed signal.
* </para>
* </listitem>
* <listitem>
* <para>
* When parent allocates space to child, scrollable widget needs to update
* properties listed under 1 with new values.
* </para>
* </listitem>
* <listitem>
* <para>
* When any of the adjustments emits #GtkAdjustment::value-changed signal,
* scrollable widget needs to scroll it's contents.
* </para>
* </listitem>
* </orderedlist>
* </para>
* </refsect2>
*/
#include "config.h"
#include "gtkscrollable.h"
#include "gtkprivate.h"
#include "gtkintl.h"
G_DEFINE_INTERFACE (GtkScrollable, gtk_scrollable, G_TYPE_OBJECT)
static void
gtk_scrollable_default_init (GtkScrollableInterface *iface)
{
GParamSpec *pspec;
/**
* GtkScrollable:hadjustment:
*
* Horizontal #GtkAdjustment of scrollable widget. This adjustment is
* shared between scrollable widget and it's parent.
*
* Since: 3.0
*/
pspec = g_param_spec_object ("hadjustment",
P_("Horizontal adjustment"),
P_("Horizontal adjustment that is shared "
"between scrollable widget and it's "
"controller"),
GTK_TYPE_ADJUSTMENT,
GTK_PARAM_READWRITE | G_PARAM_CONSTRUCT);
g_object_interface_install_property (iface, pspec);
/**
* GtkScrollable:vadjustment:
*
* Verical #GtkAdjustment of scrollable widget. This adjustment is shared
* between scrollable widget and it's parent.
*
* Since: 3.0
*/
pspec = g_param_spec_object ("vadjustment",
P_("Vertical adjustment"),
P_("Vertical adjustment that is shared "
"between scrollable widget and it's "
"controller"),
GTK_TYPE_ADJUSTMENT,
GTK_PARAM_READWRITE | G_PARAM_CONSTRUCT);
g_object_interface_install_property (iface, pspec);
/**
* GtkScrollable:min-display-width:
*
* Minimum width to display in the parent scrolled window, this
* can be greater or less than the scrollable widget's real minimum
* width.
*
* Since: 3.0
*/
pspec = g_param_spec_int ("min-display-width",
P_("Minimum Display Width"),
P_("Minimum width to display in the parent scrolled window"),
-1, G_MAXINT, -1,
GTK_PARAM_READWRITE);
g_object_interface_install_property (iface, pspec);
/**
* GtkScrollable:min-display-height:
*
* Minimum height to display in the parent scrolled window, this
* can be greater or less than the scrollable widget's real minimum
* height.
*
* Since: 3.0
*/
pspec = g_param_spec_int ("min-display-height",
P_("Minimum Display Height"),
P_("Minimum height to display in the parent scrolled window"),
-1, G_MAXINT, -1,
GTK_PARAM_READWRITE);
g_object_interface_install_property (iface, pspec);
}
/**
* gtk_scrollable_get_hadjustment:
* @scrollable: a #GtkScrollable
*
* Retrieves the #GtkAdjustment, used for horizontal scrolling.
*
* Return value: (transfer none): horizontal #GtkAdjustment.
*
* Since: 3.0
**/
GtkAdjustment *
gtk_scrollable_get_hadjustment (GtkScrollable *scrollable)
{
GtkAdjustment *adj = NULL;
g_return_val_if_fail (GTK_IS_SCROLLABLE (scrollable), NULL);
g_object_get (scrollable, "hadjustment", &adj, NULL);
/* Horrid hack; g_object_get() returns a new reference but
* that contradicts the memory management conventions
* for accessors.
*/
if (adj)
g_object_unref (adj);
return adj;
}
/**
* gtk_scrollable_set_hadjustment:
* @scrollable: a #GtkScrollable
* @hadjustment: (allow-none): a #GtkAdjustment
*
* Sets the horizontal adjustment of the #GtkScrollable.
*
* Since: 3.0
**/
void
gtk_scrollable_set_hadjustment (GtkScrollable *scrollable,
GtkAdjustment *hadjustment)
{
g_return_if_fail (GTK_IS_SCROLLABLE (scrollable));
g_return_if_fail (hadjustment == NULL || GTK_IS_ADJUSTMENT (hadjustment));
g_object_set (scrollable, "hadjustment", hadjustment, NULL);
}
/**
* gtk_scrollable_get_vadjustment:
* @scrollable: a #GtkScrollable
*
* Retrieves the #GtkAdjustment, used for vertical scrolling.
*
* Return value: (transfer none): vertical #GtkAdjustment.
*
* Since: 3.0
**/
GtkAdjustment *
gtk_scrollable_get_vadjustment (GtkScrollable *scrollable)
{
GtkAdjustment *adj = NULL;
g_return_val_if_fail (GTK_IS_SCROLLABLE (scrollable), NULL);
g_object_get (scrollable, "vadjustment", &adj, NULL);
/* Horrid hack; g_object_get() returns a new reference but
* that contradicts the memory management conventions
* for accessors.
*/
if (adj)
g_object_unref (adj);
return adj;
}
/**
* gtk_scrollable_set_vadjustment:
* @scrollable: a #GtkScrollable
* @vadjustment: (allow-none): a #GtkAdjustment
*
* Sets the vertical adjustment of the #GtkScrollable.
*
* Since: 3.0
**/
void
gtk_scrollable_set_vadjustment (GtkScrollable *scrollable,
GtkAdjustment *vadjustment)
{
g_return_if_fail (GTK_IS_SCROLLABLE (scrollable));
g_return_if_fail (vadjustment == NULL || GTK_IS_ADJUSTMENT (vadjustment));
g_object_set (scrollable, "vadjustment", vadjustment, NULL);
}
/**
* gtk_scrollable_get_min_display_width:
* @scrollable: a #GtkScrollable
*
* Retrieves the minimum width of content to display in the
* parent scrolled window.
*
* Return value: The minimum display width.
*
* Since: 3.0
**/
gint
gtk_scrollable_get_min_display_width (GtkScrollable *scrollable)
{
gint width;
g_return_val_if_fail (GTK_IS_SCROLLABLE (scrollable), 0);
g_object_get (scrollable, "min-display-width", &width, NULL);
return width;
}
/**
* gtk_scrollable_set_min_display_width:
* @scrollable: a #GtkScrollable
* @width: the minimum width of scrollable content to display
*
* Sets the minimum width of content to display in the parent scrolled window,
* this can be greater or less than the scrollable widget's real minimum
* width.
*
* Since: 3.0
**/
void
gtk_scrollable_set_min_display_width (GtkScrollable *scrollable,
gint width)
{
g_return_if_fail (GTK_IS_SCROLLABLE (scrollable));
g_object_set (scrollable, "min-display-width", width, NULL);
}
/**
* gtk_scrollable_get_min_display_height:
* @scrollable: a #GtkScrollable
*
* Retrieves the minimum height of content to display in the
* parent scrolled window.
*
* Return value: The minimum display height.
*
* Since: 3.0
**/
gint
gtk_scrollable_get_min_display_height (GtkScrollable *scrollable)
{
gint height;
g_return_val_if_fail (GTK_IS_SCROLLABLE (scrollable), 0);
g_object_get (scrollable, "min-display-height", &height, NULL);
return height;
}
/**
* gtk_scrollable_set_min_display_height:
* @scrollable: a #GtkScrollable
* @height: the minimum height of scrollable content to display
*
* Sets the minimum height of content to display in the parent scrolled window,
* this can be greater or less than the scrollable widget's real minimum
* height.
*
* Since: 3.0
**/
void
gtk_scrollable_set_min_display_height (GtkScrollable *scrollable,
gint height)
{
g_return_if_fail (GTK_IS_SCROLLABLE (scrollable));
g_object_set (scrollable, "min-display-height", height, NULL);
}