gtk2/gtk/gtkrevealer.c

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/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/*
* Copyright (c) 2013 Red Hat, Inc.
*
* This program 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 program 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 program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* Author: Alexander Larsson <alexl@redhat.com>
*
*/
#include "config.h"
#include "gtkrevealer.h"
#include <gdk/gdk.h>
#include "gtktypebuiltins.h"
#include "gtkprivate.h"
#include "gtkintl.h"
#include <math.h>
enum {
PROP_0,
PROP_TRANSITION_TYPE,
PROP_TRANSITION_DURATION,
PROP_REVEAL_CHILD,
PROP_CHILD_REVEALED
};
struct _GtkRevealerPrivate {
GtkRevealerTransitionType transition_type;
guint transition_duration;
GdkWindow* bin_window;
GdkWindow* view_window;
gdouble current_pos;
gdouble source_pos;
gdouble target_pos;
guint tick_id;
gint64 start_time;
gint64 end_time;
};
static void gtk_revealer_real_realize (GtkWidget *widget);
static void gtk_revealer_real_unrealize (GtkWidget *widget);
static void gtk_revealer_real_add (GtkContainer *widget,
GtkWidget *child);
static void gtk_revealer_real_style_updated (GtkWidget *widget);
static void gtk_revealer_real_size_allocate (GtkWidget *widget,
GtkAllocation *allocation);
static void gtk_revealer_real_map (GtkWidget *widget);
static void gtk_revealer_real_unmap (GtkWidget *widget);
static gboolean gtk_revealer_real_draw (GtkWidget *widget,
cairo_t *cr);
static void gtk_revealer_real_get_preferred_height (GtkWidget *widget,
gint *minimum_height,
gint *natural_height);
static void gtk_revealer_real_get_preferred_height_for_width (GtkWidget *widget,
gint width,
gint *minimum_height,
gint *natural_height);
static void gtk_revealer_real_get_preferred_width (GtkWidget *widget,
gint *minimum_width,
gint *natural_width);
static void gtk_revealer_real_get_preferred_width_for_height (GtkWidget *widget,
gint height,
gint *minimum_width,
gint *natural_width);
G_DEFINE_TYPE (GtkRevealer, gtk_revealer, GTK_TYPE_BIN);
static void
gtk_revealer_init (GtkRevealer *revealer)
{
GtkRevealerPrivate *priv;
priv = G_TYPE_INSTANCE_GET_PRIVATE (revealer, GTK_TYPE_REVEALER, GtkRevealerPrivate);
revealer->priv = priv;
priv->transition_type = GTK_REVEALER_TRANSITION_TYPE_SLIDE_DOWN;
priv->transition_duration = 250;
priv->current_pos = 0.0;
priv->target_pos = 0.0;
gtk_widget_set_has_window ((GtkWidget*) revealer, TRUE);
gtk_widget_set_redraw_on_allocate ((GtkWidget*) revealer, FALSE);
}
static void
gtk_revealer_finalize (GObject *obj)
{
GtkRevealer *revealer = GTK_REVEALER (obj);
GtkRevealerPrivate *priv = revealer->priv;
if (priv->tick_id != 0)
gtk_widget_remove_tick_callback (GTK_WIDGET (revealer), priv->tick_id);
priv->tick_id = 0;
G_OBJECT_CLASS (gtk_revealer_parent_class)->finalize (obj);
}
static void
gtk_revealer_get_property (GObject *object,
guint property_id,
GValue *value,
GParamSpec *pspec)
{
GtkRevealer *revealer = GTK_REVEALER (object);
switch (property_id)
{
case PROP_TRANSITION_TYPE:
g_value_set_enum (value, gtk_revealer_get_transition_type (revealer));
break;
case PROP_TRANSITION_DURATION:
g_value_set_uint (value, gtk_revealer_get_transition_duration (revealer));
break;
case PROP_REVEAL_CHILD:
g_value_set_boolean (value, gtk_revealer_get_reveal_child (revealer));
break;
case PROP_CHILD_REVEALED:
g_value_set_boolean (value, gtk_revealer_get_child_revealed (revealer));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
break;
}
}
static void
gtk_revealer_set_property (GObject *object,
guint property_id,
const GValue *value,
GParamSpec *pspec)
{
GtkRevealer *revealer = GTK_REVEALER (object);
switch (property_id)
{
case PROP_TRANSITION_TYPE:
gtk_revealer_set_transition_type (revealer, g_value_get_enum (value));
break;
case PROP_TRANSITION_DURATION:
gtk_revealer_set_transition_duration (revealer, g_value_get_uint (value));
break;
case PROP_REVEAL_CHILD:
gtk_revealer_set_reveal_child (revealer, g_value_get_boolean (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
break;
}
}
static void
gtk_revealer_class_init (GtkRevealerClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
GtkWidgetClass *widget_class = GTK_WIDGET_CLASS(klass);
GtkContainerClass *container_class = GTK_CONTAINER_CLASS (klass);
object_class->get_property = gtk_revealer_get_property;
object_class->set_property = gtk_revealer_set_property;
object_class->finalize = gtk_revealer_finalize;
widget_class->realize = gtk_revealer_real_realize;
widget_class->unrealize = gtk_revealer_real_unrealize;
widget_class->style_updated = gtk_revealer_real_style_updated;
widget_class->size_allocate = gtk_revealer_real_size_allocate;
widget_class->map = gtk_revealer_real_map;
widget_class->unmap = gtk_revealer_real_unmap;
widget_class->draw = gtk_revealer_real_draw;
widget_class->get_preferred_height = gtk_revealer_real_get_preferred_height;
widget_class->get_preferred_height_for_width = gtk_revealer_real_get_preferred_height_for_width;
widget_class->get_preferred_width = gtk_revealer_real_get_preferred_width;
widget_class->get_preferred_width_for_height = gtk_revealer_real_get_preferred_width_for_height;
container_class->add = gtk_revealer_real_add;
g_object_class_install_property (object_class,
PROP_TRANSITION_TYPE,
g_param_spec_enum ("transition-type",
P_("Transition type"),
P_("The type of animation used to transition"),
GTK_TYPE_REVEALER_TRANSITION_TYPE,
GTK_REVEALER_TRANSITION_TYPE_SLIDE_DOWN,
GTK_PARAM_READWRITE | G_PARAM_CONSTRUCT));
g_object_class_install_property (object_class,
PROP_TRANSITION_DURATION,
g_param_spec_uint ("transition-duration",
P_("Transition duration"),
P_("The animation duration, in milliseconds"),
0, G_MAXUINT,
250,
GTK_PARAM_READWRITE | G_PARAM_CONSTRUCT));
g_object_class_install_property (object_class,
PROP_REVEAL_CHILD,
g_param_spec_boolean ("reveal-child",
P_("Reveal Child"),
P_("Whether the container should reveal the child"),
FALSE,
GTK_PARAM_READWRITE | G_PARAM_CONSTRUCT));
g_object_class_install_property (object_class,
PROP_CHILD_REVEALED,
g_param_spec_boolean ("child-revealed",
P_("Child Revealed"),
P_("Whether the child is revealed and the animation target reached"),
FALSE,
G_PARAM_READABLE));
g_type_class_add_private (klass, sizeof (GtkRevealerPrivate));
}
GtkWidget *
gtk_revealer_new (void)
{
return g_object_new (GTK_TYPE_REVEALER, NULL);
}
static void
gtk_revealer_get_child_allocation (GtkRevealer *revealer,
GtkAllocation *allocation,
GtkAllocation *child_allocation)
{
GtkWidget *child;
GtkRevealerPrivate *priv;
g_return_if_fail (revealer != NULL);
g_return_if_fail (allocation != NULL);
priv = revealer->priv;
child_allocation->x = 0;
child_allocation->y = 0;
child_allocation->width = allocation->width;
child_allocation->height = allocation->height;
child = gtk_bin_get_child (GTK_BIN (revealer));
if (child != NULL && gtk_widget_get_visible (child))
{
if (priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_LEFT ||
priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_RIGHT)
gtk_widget_get_preferred_width_for_height (child, child_allocation->height, NULL,
&child_allocation->width);
else
gtk_widget_get_preferred_height_for_width (child, child_allocation->width, NULL,
&child_allocation->height);
}
}
static void
gtk_revealer_real_realize (GtkWidget *widget)
{
GtkRevealer *revealer = GTK_REVEALER (widget);
GtkRevealerPrivate *priv = revealer->priv;
GtkAllocation allocation;
GdkWindowAttr attributes = { 0 };
GdkWindowAttributesType attributes_mask;
GtkAllocation child_allocation;
GtkWidget *child;
GtkStyleContext *context;
gtk_widget_set_realized (widget, TRUE);
gtk_widget_get_allocation (widget, &allocation);
attributes.x = allocation.x;
attributes.y = allocation.y;
attributes.width = allocation.width;
attributes.height = allocation.height;
attributes.window_type = GDK_WINDOW_CHILD;
attributes.wclass = GDK_INPUT_OUTPUT;
attributes.visual = gtk_widget_get_visual (widget);
attributes.event_mask =
gtk_widget_get_events (widget) | GDK_EXPOSURE_MASK;
attributes_mask = (GDK_WA_X | GDK_WA_Y) | GDK_WA_VISUAL;
priv->view_window =
gdk_window_new (gtk_widget_get_parent_window ((GtkWidget*) revealer),
&attributes, attributes_mask);
gtk_widget_set_window (widget, priv->view_window);
gtk_widget_register_window (widget, priv->view_window);
gtk_revealer_get_child_allocation (revealer, &allocation, &child_allocation);
attributes.x = 0;
attributes.y = 0;
attributes.width = child_allocation.width;
attributes.height = child_allocation.height;
if (priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_DOWN)
attributes.y = allocation.height - child_allocation.height;
else if (priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_RIGHT)
attributes.x = allocation.width - child_allocation.width;
priv->bin_window =
gdk_window_new (priv->view_window, &attributes, attributes_mask);
gtk_widget_register_window (widget, priv->bin_window);
child = gtk_bin_get_child (GTK_BIN (revealer));
if (child != NULL)
gtk_widget_set_parent_window (child, priv->bin_window);
context = gtk_widget_get_style_context (widget);
gtk_style_context_set_background (context, priv->view_window);
gtk_style_context_set_background (context, priv->bin_window);
gdk_window_show (priv->bin_window);
}
static void
gtk_revealer_real_unrealize (GtkWidget *widget)
{
GtkRevealer *revealer = GTK_REVEALER (widget);
GtkRevealerPrivate *priv = revealer->priv;
gtk_widget_unregister_window (widget, priv->bin_window);
gdk_window_destroy (priv->bin_window);
priv->view_window = NULL;
GTK_WIDGET_CLASS (gtk_revealer_parent_class)->unrealize (widget);
}
static void
gtk_revealer_real_add (GtkContainer *container,
GtkWidget *child)
{
GtkRevealer *revealer = GTK_REVEALER (container);
GtkRevealerPrivate *priv = revealer->priv;
g_return_if_fail (child != NULL);
gtk_widget_set_parent_window (child, priv->bin_window);
gtk_widget_set_child_visible (child, priv->current_pos != 0.0);
GTK_CONTAINER_CLASS (gtk_revealer_parent_class)->add (container, child);
}
static void
gtk_revealer_real_style_updated (GtkWidget *widget)
{
GtkRevealer *revealer = GTK_REVEALER (widget);
GtkRevealerPrivate *priv = revealer->priv;
GtkStyleContext* context;
GTK_WIDGET_CLASS (gtk_revealer_parent_class)->style_updated (widget);
if (gtk_widget_get_realized (widget))
{
context = gtk_widget_get_style_context (widget);
gtk_style_context_set_background (context, priv->bin_window);
gtk_style_context_set_background (context, priv->view_window);
}
}
static void
gtk_revealer_real_size_allocate (GtkWidget *widget,
GtkAllocation *allocation)
{
GtkRevealer *revealer = GTK_REVEALER (widget);
GtkRevealerPrivate *priv = revealer->priv;
GtkAllocation child_allocation;
GtkWidget *child;
gboolean window_visible;
int bin_x, bin_y;
g_return_if_fail (allocation != NULL);
gtk_widget_set_allocation (widget, allocation);
gtk_revealer_get_child_allocation (revealer, allocation, &child_allocation);
child = gtk_bin_get_child (GTK_BIN (revealer));
if (child != NULL && gtk_widget_get_visible (child))
gtk_widget_size_allocate (child, &child_allocation);
if (gtk_widget_get_realized (widget))
{
if (gtk_widget_get_mapped (widget))
{
window_visible = allocation->width > 0 && allocation->height > 0;
if (!window_visible && gdk_window_is_visible (priv->view_window))
gdk_window_hide (priv->view_window);
if (window_visible && !gdk_window_is_visible (priv->view_window))
gdk_window_show (priv->view_window);
}
gdk_window_move_resize (priv->view_window,
allocation->x, allocation->y,
allocation->width, allocation->height);
bin_x = 0;
bin_y = 0;
if (priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_DOWN)
bin_y = allocation->height - child_allocation.height;
else if (priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_RIGHT)
bin_x = allocation->width - child_allocation.width;
gdk_window_move_resize (priv->bin_window,
bin_x, bin_y,
child_allocation.width, child_allocation.height);
}
}
static void
gtk_revealer_set_position (GtkRevealer *revealer,
gdouble pos)
{
GtkRevealerPrivate *priv = revealer->priv;
gboolean new_visible;
GtkWidget *child;
priv->current_pos = pos;
/* We check target_pos here too, because we want to ensure we set
* child_visible immediately when starting a reveal operation
* otherwise the child widgets will not be properly realized
* after the reveal returns.
*/
new_visible = priv->current_pos != 0.0 || priv->target_pos != 0.0;
child = gtk_bin_get_child (GTK_BIN (revealer));
if (child != NULL &&
new_visible != gtk_widget_get_child_visible (child))
gtk_widget_set_child_visible (child, new_visible);
if (priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_CROSSFADE)
{
gtk_widget_set_opacity (GTK_WIDGET (revealer), priv->current_pos);
gtk_widget_queue_draw (GTK_WIDGET (revealer));
}
else
{
gtk_widget_queue_resize (GTK_WIDGET (revealer));
}
if (priv->current_pos == priv->target_pos)
g_object_notify (G_OBJECT (revealer), "child-revealed");
}
static gdouble
ease_out_quad (gdouble t, gdouble d)
{
gdouble p = t / d;
return ((-1.0) * p) * (p - 2);
}
static void
gtk_revealer_animate_step (GtkRevealer *revealer,
gint64 now)
{
GtkRevealerPrivate *priv = revealer->priv;
gdouble t;
t = 1.0;
if (now < priv->end_time)
t = (now - priv->start_time) / (gdouble) (priv->end_time - priv->start_time);
t = ease_out_quad (t, 1.0);
gtk_revealer_set_position (revealer,
priv->source_pos + (t * (priv->target_pos - priv->source_pos)));
}
static gboolean
gtk_revealer_animate_cb (GtkRevealer *revealer,
GdkFrameClock *frame_clock,
gpointer user_data)
{
GtkRevealerPrivate *priv = revealer->priv;
gint64 now;
now = gdk_frame_clock_get_frame_time (frame_clock);
gtk_revealer_animate_step (revealer, now);
if (priv->current_pos == priv->target_pos)
{
priv->tick_id = 0;
return FALSE;
}
return TRUE;
}
static void
gtk_revealer_start_animation (GtkRevealer *revealer,
gdouble target)
{
GtkRevealerPrivate *priv = revealer->priv;
GtkWidget *widget = GTK_WIDGET (revealer);
if (priv->target_pos == target)
return;
priv->target_pos = target;
g_object_notify (G_OBJECT (revealer), "reveal-child");
if (gtk_widget_get_mapped (widget) &&
priv->transition_duration != 0 &&
priv->transition_type != GTK_REVEALER_TRANSITION_TYPE_NONE)
{
priv->source_pos = priv->current_pos;
priv->start_time = gdk_frame_clock_get_frame_time (gtk_widget_get_frame_clock (widget));
priv->end_time = priv->start_time + (priv->transition_duration * 1000);
if (priv->tick_id == 0)
priv->tick_id =
gtk_widget_add_tick_callback (widget, (GtkTickCallback)gtk_revealer_animate_cb, revealer, NULL);
gtk_revealer_animate_step (revealer, priv->start_time);
}
else
{
gtk_revealer_set_position (revealer, target);
}
}
static void
gtk_revealer_stop_animation (GtkRevealer *revealer)
{
GtkRevealerPrivate *priv = revealer->priv;
priv->current_pos = priv->target_pos;
if (priv->tick_id != 0)
{
gtk_widget_remove_tick_callback (GTK_WIDGET (revealer), priv->tick_id);
priv->tick_id = 0;
}
}
static void
gtk_revealer_real_map (GtkWidget *widget)
{
GtkRevealer *revealer = GTK_REVEALER (widget);
GtkRevealerPrivate *priv = revealer->priv;
GtkAllocation allocation;
if (!gtk_widget_get_mapped (widget))
{
gtk_widget_get_allocation (widget, &allocation);
if (allocation.width > 0 && allocation.height > 0)
gdk_window_show (priv->view_window);
gtk_revealer_start_animation (revealer, priv->target_pos);
}
GTK_WIDGET_CLASS (gtk_revealer_parent_class)->map (widget);
}
static void
gtk_revealer_real_unmap (GtkWidget *widget)
{
GtkRevealer *revealer = GTK_REVEALER (widget);
GTK_WIDGET_CLASS (gtk_revealer_parent_class)->unmap (widget);
gtk_revealer_stop_animation (revealer);
}
static gboolean
gtk_revealer_real_draw (GtkWidget *widget,
cairo_t *cr)
{
GtkRevealer *revealer = GTK_REVEALER (widget);
GtkRevealerPrivate *priv = revealer->priv;
if (gtk_cairo_should_draw_window (cr, priv->bin_window))
GTK_WIDGET_CLASS (gtk_revealer_parent_class)->draw (widget, cr);
return TRUE;
}
void
gtk_revealer_set_reveal_child (GtkRevealer *revealer,
gboolean reveal_child)
{
g_return_if_fail (GTK_IS_REVEALER (revealer));
if (reveal_child)
gtk_revealer_start_animation (revealer, 1.0);
else
gtk_revealer_start_animation (revealer, 0.0);
}
gboolean
gtk_revealer_get_reveal_child (GtkRevealer *revealer)
{
g_return_val_if_fail (GTK_IS_REVEALER (revealer), FALSE);
return revealer->priv->target_pos != 0.0;
}
gboolean
gtk_revealer_get_child_revealed (GtkRevealer *revealer)
{
gboolean animation_finished = (revealer->priv->target_pos == revealer->priv->current_pos);
gboolean reveal_child = gtk_revealer_get_reveal_child (revealer);
if (animation_finished)
return reveal_child;
else
return !reveal_child;
}
/* These all report only the natural size, ignoring the minimal size,
* because its not really possible to allocate the right size during
* animation if the child size can change (without the child
* re-arranging itself during the animation).
*/
static void
gtk_revealer_real_get_preferred_height (GtkWidget *widget,
gint *minimum_height_out,
gint *natural_height_out)
{
GtkRevealer *revealer = GTK_REVEALER (widget);
GtkRevealerPrivate *priv = revealer->priv;
gint minimum_height;
gint natural_height;
GTK_WIDGET_CLASS (gtk_revealer_parent_class)->get_preferred_height (widget, &minimum_height, &natural_height);
if (priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_UP ||
priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_DOWN)
natural_height = round (natural_height * priv->current_pos);
minimum_height = natural_height;
if (minimum_height_out)
*minimum_height_out = minimum_height;
if (natural_height_out)
*natural_height_out = natural_height;
}
static void
gtk_revealer_real_get_preferred_height_for_width (GtkWidget *widget,
gint width,
gint *minimum_height_out,
gint *natural_height_out)
{
GtkRevealer *revealer = GTK_REVEALER (widget);
GtkRevealerPrivate *priv = revealer->priv;
gint minimum_height;
gint natural_height;
GTK_WIDGET_CLASS (gtk_revealer_parent_class)->get_preferred_height_for_width (widget, width, &minimum_height, &natural_height);
if (priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_UP ||
priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_DOWN)
natural_height = round (natural_height * priv->current_pos);
minimum_height = natural_height;
if (minimum_height_out)
*minimum_height_out = minimum_height;
if (natural_height_out)
*natural_height_out = natural_height;
}
static void
gtk_revealer_real_get_preferred_width (GtkWidget *widget,
gint *minimum_width_out,
gint *natural_width_out)
{
GtkRevealer *revealer = GTK_REVEALER (widget);
GtkRevealerPrivate *priv = revealer->priv;
gint minimum_width;
gint natural_width;
GTK_WIDGET_CLASS (gtk_revealer_parent_class)->get_preferred_width (widget, &minimum_width, &natural_width);
if (priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_LEFT ||
priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_RIGHT)
natural_width = round (natural_width * priv->current_pos);
minimum_width = natural_width;
if (minimum_width_out)
*minimum_width_out = minimum_width;
if (natural_width_out)
*natural_width_out = natural_width;
}
static void
gtk_revealer_real_get_preferred_width_for_height (GtkWidget *widget,
gint height,
gint *minimum_width_out,
gint *natural_width_out)
{
GtkRevealer *revealer = GTK_REVEALER (widget);
GtkRevealerPrivate *priv = revealer->priv;
gint minimum_width;
gint natural_width;
GTK_WIDGET_CLASS (gtk_revealer_parent_class)->get_preferred_width_for_height (widget, height, &minimum_width, &natural_width);
if (priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_LEFT ||
priv->transition_type == GTK_REVEALER_TRANSITION_TYPE_SLIDE_RIGHT)
natural_width = round (natural_width * priv->current_pos);
minimum_width = natural_width;
if (minimum_width_out)
*minimum_width_out = minimum_width;
if (natural_width_out)
*natural_width_out = natural_width;
}
guint
gtk_revealer_get_transition_duration (GtkRevealer *revealer)
{
g_return_val_if_fail (GTK_IS_REVEALER (revealer), 0);
return revealer->priv->transition_duration;
}
void
gtk_revealer_set_transition_duration (GtkRevealer *revealer,
guint value)
{
g_return_if_fail (GTK_IS_REVEALER (revealer));
revealer->priv->transition_duration = value;
g_object_notify (G_OBJECT (revealer), "transition-duration");
}
GtkRevealerTransitionType
gtk_revealer_get_transition_type (GtkRevealer *revealer)
{
g_return_val_if_fail (GTK_IS_REVEALER (revealer), GTK_REVEALER_TRANSITION_TYPE_NONE);
return revealer->priv->transition_type;
}
void
gtk_revealer_set_transition_type (GtkRevealer *revealer,
GtkRevealerTransitionType transition)
{
g_return_if_fail (GTK_IS_REVEALER (revealer));
revealer->priv->transition_type = transition;
gtk_widget_queue_resize (GTK_WIDGET (revealer));
g_object_notify (G_OBJECT (revealer), "transition-type");
}