gnome-shell/src/st/st-scroll-view.c

1135 lines
34 KiB
C
Raw Normal View History

/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
/*
* st-scroll-view.h: Container with scroll-bars
*
* Copyright 2008 OpenedHand
* Copyright 2009 Intel Corporation.
* Copyright 2009, 2010 Red Hat, Inc.
* Copyright 2010 Maxim Ermilov
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU Lesser General Public License,
* version 2.1, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
*/
/**
* SECTION:st-scroll-view
* @short_description: a container for scrollable children
*
* #StScrollView is a single child container for actors that implement
* #StScrollable. It provides scrollbars around the edge of the child to
* allow the user to move around the scrollable area.
*/
/* TODO: The code here currently only deals with height-for-width
* allocation; width-for-height allocation would need a second set of
* code paths through get_preferred_height()/get_preferred_width()/allocate()
* that reverse the roles of the horizontal and vertical scrollbars.
*
* TODO: The multiple layout passes with and without scrollbars when
* using the automatic policy causes considerable inefficiency because
* it breaks request caching; we should saved the last size passed
* into allocate() and if it's the same as previous size not repeat
* the determination of scrollbar visibility. This requires overriding
* queue_relayout() so we know when to discard the saved value.
*
* The size negotiation between the #StScrollView and the child is
* described in the documentation for #StScrollable; the significant
* part to note there is that reported minimum sizes for a scrolled
* child are the minimum sizes when no scrollbar is needed. This allows
* us to determine what scrollbars are visible without a need to look
* inside the #StAdjustment.
*
* The second simplification that we make that allows us to implement
* a straighforward height-for-width negotiation without multiple
* allocate passes is that when the vertical scrollbar policy is
* AUTO, we always reserve space for the vertical scrollbar in the
* reported minimum and natural size.
*
* See https://bugzilla.gnome.org/show_bug.cgi?id=611740 for a more
* detailed description of the considerations involved.
*/
#include "st-scroll-view.h"
#include "st-scroll-bar.h"
#include "st-scrollable.h"
#include "st-scroll-view-fade.h"
#include <clutter/clutter.h>
#include <math.h>
static void clutter_container_iface_init (ClutterContainerIface *iface);
static ClutterContainerIface *st_scroll_view_parent_iface = NULL;
G_DEFINE_TYPE_WITH_CODE (StScrollView, st_scroll_view, ST_TYPE_BIN,
G_IMPLEMENT_INTERFACE (CLUTTER_TYPE_CONTAINER,
clutter_container_iface_init))
#define SCROLL_VIEW_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), \
ST_TYPE_SCROLL_VIEW, \
StScrollViewPrivate))
struct _StScrollViewPrivate
{
/* a pointer to the child; this is actually stored
* inside StBin:child, but we keep it to avoid
* calling st_bin_get_child() every time we need it
*/
ClutterActor *child;
StAdjustment *hadjustment;
ClutterActor *hscroll;
StAdjustment *vadjustment;
ClutterActor *vscroll;
GtkPolicyType hscrollbar_policy;
GtkPolicyType vscrollbar_policy;
gfloat row_size;
gfloat column_size;
StScrollViewFade *vfade_effect;
gboolean row_size_set : 1;
gboolean column_size_set : 1;
guint mouse_scroll : 1;
guint hscrollbar_visible : 1;
guint vscrollbar_visible : 1;
};
enum {
PROP_0,
PROP_HSCROLL,
PROP_VSCROLL,
PROP_HSCROLLBAR_POLICY,
PROP_VSCROLLBAR_POLICY,
PROP_HSCROLLBAR_VISIBLE,
PROP_VSCROLLBAR_VISIBLE,
PROP_MOUSE_SCROLL,
};
static void
st_scroll_view_get_property (GObject *object,
guint property_id,
GValue *value,
GParamSpec *pspec)
{
StScrollViewPrivate *priv = ((StScrollView *) object)->priv;
switch (property_id)
{
case PROP_HSCROLL:
g_value_set_object (value, priv->hscroll);
break;
case PROP_VSCROLL:
g_value_set_object (value, priv->vscroll);
break;
case PROP_HSCROLLBAR_POLICY:
g_value_set_enum (value, priv->hscrollbar_policy);
break;
case PROP_VSCROLLBAR_POLICY:
g_value_set_enum (value, priv->vscrollbar_policy);
break;
case PROP_HSCROLLBAR_VISIBLE:
g_value_set_boolean (value, priv->hscrollbar_visible);
break;
case PROP_VSCROLLBAR_VISIBLE:
g_value_set_boolean (value, priv->vscrollbar_visible);
break;
case PROP_MOUSE_SCROLL:
g_value_set_boolean (value, priv->mouse_scroll);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}
}
/**
* st_scroll_view_update_vfade_effect:
* @self: a #StScrollView
* @fade_offset: The length of the fade effect, in pixels.
*
* Sets the height of the fade area area in pixels. A value of 0
* disables the effect.
*/
static void
st_scroll_view_update_vfade_effect (StScrollView *self,
float fade_offset)
{
StScrollViewPrivate *priv = ST_SCROLL_VIEW (self)->priv;
/* A fade amount of more than 0 enables the effect. */
if (fade_offset > 0.)
{
if (priv->vfade_effect == NULL) {
priv->vfade_effect = g_object_new (ST_TYPE_SCROLL_VIEW_FADE, NULL);
clutter_actor_add_effect_with_name (CLUTTER_ACTOR (self), "vfade",
CLUTTER_EFFECT (priv->vfade_effect));
}
g_object_set (priv->vfade_effect,
"fade-offset", fade_offset,
NULL);
}
else
{
if (priv->vfade_effect != NULL) {
clutter_actor_remove_effect (CLUTTER_ACTOR (self), CLUTTER_EFFECT (priv->vfade_effect));
priv->vfade_effect = NULL;
}
}
clutter_actor_queue_redraw (CLUTTER_ACTOR (self));
}
static void
st_scroll_view_set_property (GObject *object,
guint property_id,
const GValue *value,
GParamSpec *pspec)
{
StScrollView *self = ST_SCROLL_VIEW (object);
StScrollViewPrivate *priv = self->priv;
switch (property_id)
{
case PROP_MOUSE_SCROLL:
st_scroll_view_set_mouse_scrolling (self,
g_value_get_boolean (value));
break;
case PROP_HSCROLLBAR_POLICY:
st_scroll_view_set_policy (self,
g_value_get_enum (value),
priv->vscrollbar_policy);
break;
case PROP_VSCROLLBAR_POLICY:
st_scroll_view_set_policy (self,
priv->hscrollbar_policy,
g_value_get_enum (value));
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
}
}
static void
st_scroll_view_dispose (GObject *object)
{
StScrollViewPrivate *priv = ST_SCROLL_VIEW (object)->priv;
if (priv->vfade_effect)
{
clutter_actor_remove_effect (CLUTTER_ACTOR (object), CLUTTER_EFFECT (priv->vfade_effect));
priv->vfade_effect = NULL;
}
if (priv->vscroll)
clutter_actor_destroy (priv->vscroll);
if (priv->hscroll)
clutter_actor_destroy (priv->hscroll);
/* For most reliable freeing of memory, an object with signals
* like StAdjustment should be explicitly disposed. Since we own
* the adjustments, we take care of that. This also disconnects
* the signal handlers that we established on creation.
*/
if (priv->hadjustment)
{
g_object_run_dispose (G_OBJECT (priv->hadjustment));
g_object_unref (priv->hadjustment);
priv->hadjustment = NULL;
}
if (priv->vadjustment)
{
g_object_run_dispose (G_OBJECT (priv->vadjustment));
g_object_unref (priv->vadjustment);
priv->vadjustment = NULL;
}
G_OBJECT_CLASS (st_scroll_view_parent_class)->dispose (object);
}
static void
st_scroll_view_paint (ClutterActor *actor)
{
StScrollViewPrivate *priv = ST_SCROLL_VIEW (actor)->priv;
/* StBin will paint the child */
CLUTTER_ACTOR_CLASS (st_scroll_view_parent_class)->paint (actor);
/* paint our custom children */
if (priv->hscrollbar_visible)
clutter_actor_paint (priv->hscroll);
if (priv->vscrollbar_visible)
clutter_actor_paint (priv->vscroll);
}
static void
st_scroll_view_pick (ClutterActor *actor,
const ClutterColor *color)
{
StScrollViewPrivate *priv = ST_SCROLL_VIEW (actor)->priv;
/* Chain up so we get a bounding box pained (if we are reactive) */
CLUTTER_ACTOR_CLASS (st_scroll_view_parent_class)->pick (actor, color);
/* paint our custom children */
if (priv->hscrollbar_visible)
clutter_actor_paint (priv->hscroll);
if (priv->vscrollbar_visible)
clutter_actor_paint (priv->vscroll);
}
static double
get_scrollbar_width (StScrollView *scroll,
gfloat for_height)
{
StScrollViewPrivate *priv = scroll->priv;
if (CLUTTER_ACTOR_IS_VISIBLE (priv->vscroll))
{
gfloat min_size;
clutter_actor_get_preferred_width (CLUTTER_ACTOR (priv->vscroll), for_height,
&min_size, NULL);
return min_size;
}
else
return 0;
}
static double
get_scrollbar_height (StScrollView *scroll,
gfloat for_width)
{
StScrollViewPrivate *priv = scroll->priv;
if (CLUTTER_ACTOR_IS_VISIBLE (priv->hscroll))
{
gfloat min_size;
clutter_actor_get_preferred_height (CLUTTER_ACTOR (priv->hscroll), for_width,
&min_size, NULL);
return min_size;
}
else
return 0;
}
static void
st_scroll_view_get_preferred_width (ClutterActor *actor,
gfloat for_height,
gfloat *min_width_p,
gfloat *natural_width_p)
{
StScrollViewPrivate *priv = ST_SCROLL_VIEW (actor)->priv;
StThemeNode *theme_node = st_widget_get_theme_node (ST_WIDGET (actor));
gboolean account_for_vscrollbar = FALSE;
gfloat min_width = 0, natural_width;
gfloat child_min_width, child_natural_width;
if (!priv->child)
return;
st_theme_node_adjust_for_height (theme_node, &for_height);
clutter_actor_get_preferred_width (priv->child, -1,
&child_min_width, &child_natural_width);
natural_width = child_natural_width;
switch (priv->hscrollbar_policy)
{
case GTK_POLICY_NEVER:
min_width = child_min_width;
break;
case GTK_POLICY_ALWAYS:
case GTK_POLICY_AUTOMATIC:
/* Should theoretically use the min width of the hscrollbar,
* but that's not cleanly defined at the moment */
min_width = 0;
break;
}
switch (priv->vscrollbar_policy)
{
case GTK_POLICY_NEVER:
account_for_vscrollbar = FALSE;
break;
case GTK_POLICY_ALWAYS:
account_for_vscrollbar = TRUE;
break;
case GTK_POLICY_AUTOMATIC:
/* For automatic scrollbars, we always request space for the vertical
* scrollbar; we won't know whether we actually need one until our
* height is assigned in allocate().
*/
account_for_vscrollbar = TRUE;
break;
}
account_for_vscrollbar = priv->vscrollbar_policy != GTK_POLICY_NEVER;
if (account_for_vscrollbar)
{
float sb_width = get_scrollbar_width (ST_SCROLL_VIEW (actor), for_height);
min_width += sb_width;
natural_width += sb_width;
}
if (min_width_p)
*min_width_p = min_width;
if (natural_width_p)
*natural_width_p = natural_width;
st_theme_node_adjust_preferred_width (theme_node, min_width_p, natural_width_p);
}
static void
st_scroll_view_get_preferred_height (ClutterActor *actor,
gfloat for_width,
gfloat *min_height_p,
gfloat *natural_height_p)
{
StScrollViewPrivate *priv = ST_SCROLL_VIEW (actor)->priv;
StThemeNode *theme_node = st_widget_get_theme_node (ST_WIDGET (actor));
gboolean account_for_hscrollbar = FALSE;
gfloat min_height = 0, natural_height;
gfloat child_min_height, child_natural_height;
gfloat child_min_width;
gfloat sb_width;
if (!priv->child)
return;
st_theme_node_adjust_for_width (theme_node, &for_width);
clutter_actor_get_preferred_width (priv->child, -1,
&child_min_width, NULL);
if (min_height_p)
*min_height_p = 0;
sb_width = get_scrollbar_width (ST_SCROLL_VIEW (actor), -1);
switch (priv->vscrollbar_policy)
{
case GTK_POLICY_NEVER:
break;
case GTK_POLICY_ALWAYS:
case GTK_POLICY_AUTOMATIC:
/* We've requested space for the scrollbar, subtract it back out */
for_width -= sb_width;
break;
}
switch (priv->hscrollbar_policy)
{
case GTK_POLICY_NEVER:
account_for_hscrollbar = FALSE;
break;
case GTK_POLICY_ALWAYS:
account_for_hscrollbar = TRUE;
break;
case GTK_POLICY_AUTOMATIC:
account_for_hscrollbar = for_width < child_min_width;
break;
}
clutter_actor_get_preferred_height (priv->child, for_width,
&child_min_height, &child_natural_height);
natural_height = child_natural_height;
switch (priv->vscrollbar_policy)
{
case GTK_POLICY_NEVER:
min_height = child_min_height;
break;
case GTK_POLICY_ALWAYS:
case GTK_POLICY_AUTOMATIC:
/* Should theoretically use the min height of the vscrollbar,
* but that's not cleanly defined at the moment */
min_height = 0;
break;
}
if (account_for_hscrollbar)
{
float sb_height = get_scrollbar_height (ST_SCROLL_VIEW (actor), for_width);
min_height += sb_height;
natural_height += sb_height;
}
if (min_height_p)
*min_height_p = min_height;
if (natural_height_p)
*natural_height_p = natural_height;
st_theme_node_adjust_preferred_height (theme_node, min_height_p, natural_height_p);
}
static void
st_scroll_view_allocate (ClutterActor *actor,
const ClutterActorBox *box,
ClutterAllocationFlags flags)
{
ClutterActorBox content_box, child_box;
ClutterActorClass *parent_parent_class;
gfloat avail_width, avail_height, sb_width, sb_height;
gboolean hscrollbar_visible, vscrollbar_visible;
StScrollViewPrivate *priv = ST_SCROLL_VIEW (actor)->priv;
StThemeNode *theme_node = st_widget_get_theme_node (ST_WIDGET (actor));
/* Chain up to the parent's parent class
*
* We do this because we do not want StBin to allocate the child, as we
* give it a different allocation later, depending on whether the scrollbars
* are visible
*/
parent_parent_class
= g_type_class_peek_parent (st_scroll_view_parent_class);
CLUTTER_ACTOR_CLASS (parent_parent_class)->
allocate (actor, box, flags);
st_theme_node_get_content_box (theme_node, box, &content_box);
avail_width = content_box.x2 - content_box.x1;
avail_height = content_box.y2 - content_box.y1;
if (clutter_actor_get_request_mode (actor) == CLUTTER_REQUEST_HEIGHT_FOR_WIDTH)
{
sb_width = get_scrollbar_width (ST_SCROLL_VIEW (actor), -1);
sb_height = get_scrollbar_height (ST_SCROLL_VIEW (actor), sb_width);
}
else
{
sb_height = get_scrollbar_height (ST_SCROLL_VIEW (actor), -1);
sb_width = get_scrollbar_width (ST_SCROLL_VIEW (actor), sb_height);
}
/* Determine what scrollbars are visible. The basic idea of the
* handling of an automatic scrollbars is that we start off with the
* assumption that we don't need any scrollbars, see if that works,
* and if not add horizontal and vertical scrollbars until we are no
* longer overflowing.
*/
if (priv->child)
{
gfloat child_min_width;
gfloat child_min_height;
clutter_actor_get_preferred_width (priv->child, -1,
&child_min_width, NULL);
if (priv->vscrollbar_policy == GTK_POLICY_AUTOMATIC)
{
if (priv->hscrollbar_policy == GTK_POLICY_AUTOMATIC)
{
/* Pass one, try without a vertical scrollbar */
clutter_actor_get_preferred_height (priv->child, avail_width, &child_min_height, NULL);
vscrollbar_visible = child_min_height > avail_height;
hscrollbar_visible = child_min_width > avail_width - (vscrollbar_visible ? sb_width : 0);
vscrollbar_visible = child_min_height > avail_height - (hscrollbar_visible ? sb_height : 0);
/* Pass two - if we needed a vertical scrollbar, get a new preferred height */
if (vscrollbar_visible)
{
clutter_actor_get_preferred_height (priv->child, MAX (avail_width - sb_width, 0),
&child_min_height, NULL);
hscrollbar_visible = child_min_width > avail_width - sb_width;
}
}
else
{
hscrollbar_visible = priv->hscrollbar_policy != GTK_POLICY_NEVER;
/* try without a vertical scrollbar */
clutter_actor_get_preferred_height (priv->child, avail_width, &child_min_height, NULL);
vscrollbar_visible = child_min_height > avail_height - (hscrollbar_visible ? sb_height : 0);
}
}
else
{
vscrollbar_visible = priv->vscrollbar_policy != GTK_POLICY_NEVER;
if (priv->hscrollbar_policy == GTK_POLICY_AUTOMATIC)
hscrollbar_visible = child_min_width > avail_height - (vscrollbar_visible ? 0 : sb_width);
else
hscrollbar_visible = priv->hscrollbar_policy != GTK_POLICY_NEVER;
}
}
else
{
hscrollbar_visible = priv->hscrollbar_policy != GTK_POLICY_NEVER;
vscrollbar_visible = priv->vscrollbar_policy != GTK_POLICY_NEVER;
}
/* Whether or not we show the scrollbars, if the scrollbars are visible
* actors, we need to give them some allocation, so we unconditionally
* give them the "right" allocation; that might overlap the child when
* the scrollbars are not visible, but it doesn't matter because we
* don't include them in pick or paint.
*/
/* Vertical scrollbar */
if (CLUTTER_ACTOR_IS_VISIBLE (priv->vscroll))
{
if (st_widget_get_direction (ST_WIDGET (actor)) == ST_TEXT_DIRECTION_RTL)
{
child_box.x1 = content_box.x1;
child_box.x2 = content_box.x1 + sb_width;
}
else
{
child_box.x1 = content_box.x2 - sb_width;
child_box.x2 = content_box.x2;
}
child_box.y1 = content_box.y1;
child_box.y2 = content_box.y2 - (hscrollbar_visible ? sb_height : 0);
clutter_actor_allocate (priv->vscroll, &child_box, flags);
}
/* Horizontal scrollbar */
if (CLUTTER_ACTOR_IS_VISIBLE (priv->hscroll))
{
if (st_widget_get_direction (ST_WIDGET (actor)) == ST_TEXT_DIRECTION_RTL)
{
child_box.x1 = content_box.x1 + (vscrollbar_visible ? sb_width : 0);
child_box.x2 = content_box.x2;
}
else
{
child_box.x1 = content_box.x1;
child_box.x2 = content_box.x2 - (vscrollbar_visible ? sb_width : 0);
}
child_box.y1 = content_box.y2 - sb_height;
child_box.y2 = content_box.y2;
clutter_actor_allocate (priv->hscroll, &child_box, flags);
}
/* Now fold visibility into the scrollbar sizes to simplify the rest
* of the computations.
*/
if (!hscrollbar_visible)
sb_height = 0;
if (!vscrollbar_visible)
sb_width = 0;
/* Child */
if (st_widget_get_direction (ST_WIDGET (actor)) == ST_TEXT_DIRECTION_RTL)
{
child_box.x1 = content_box.x1 + sb_width;
child_box.x2 = content_box.x2;
}
else
{
child_box.x1 = content_box.x1;
child_box.x2 = content_box.x2 - sb_width;
}
child_box.y1 = content_box.y1;
child_box.y2 = content_box.y2 - sb_height;
if (priv->child)
clutter_actor_allocate (priv->child, &child_box, flags);
if (priv->hscrollbar_visible != hscrollbar_visible)
{
g_object_freeze_notify (G_OBJECT (actor));
priv->hscrollbar_visible = hscrollbar_visible;
g_object_notify (G_OBJECT (actor), "hscrollbar-visible");
g_object_thaw_notify (G_OBJECT (actor));
}
if (priv->vscrollbar_visible != vscrollbar_visible)
{
g_object_freeze_notify (G_OBJECT (actor));
priv->vscrollbar_visible = vscrollbar_visible;
g_object_notify (G_OBJECT (actor), "vscrollbar-visible");
g_object_thaw_notify (G_OBJECT (actor));
}
}
static void
st_scroll_view_style_changed (StWidget *widget)
{
StScrollView *self = ST_SCROLL_VIEW (widget);
StScrollViewPrivate *priv = self->priv;
StThemeNode *theme_node = st_widget_get_theme_node (widget);
gdouble fade_offset = st_theme_node_get_length (theme_node, "-st-vfade-offset");
st_scroll_view_update_vfade_effect (self, fade_offset);
st_widget_style_changed (ST_WIDGET (priv->hscroll));
st_widget_style_changed (ST_WIDGET (priv->vscroll));
ST_WIDGET_CLASS (st_scroll_view_parent_class)->style_changed (widget);
}
static gboolean
st_scroll_view_scroll_event (ClutterActor *self,
ClutterScrollEvent *event)
{
StScrollViewPrivate *priv = ST_SCROLL_VIEW (self)->priv;
gdouble lower, value, upper, step;
/* don't handle scroll events if requested not to */
if (!priv->mouse_scroll)
return FALSE;
switch (event->direction)
{
case CLUTTER_SCROLL_UP:
case CLUTTER_SCROLL_DOWN:
g_object_get (priv->vadjustment,
"lower", &lower,
"step-increment", &step,
"value", &value,
"upper", &upper,
NULL);
break;
case CLUTTER_SCROLL_LEFT:
case CLUTTER_SCROLL_RIGHT:
g_object_get (priv->hadjustment,
"lower", &lower,
"step-increment", &step,
"value", &value,
"upper", &upper,
NULL);
break;
}
switch (event->direction)
{
case CLUTTER_SCROLL_UP:
if (value == lower)
return FALSE;
else
st_adjustment_set_value (priv->vadjustment, value - step);
break;
case CLUTTER_SCROLL_DOWN:
if (value == upper)
return FALSE;
else
st_adjustment_set_value (priv->vadjustment, value + step);
break;
case CLUTTER_SCROLL_LEFT:
if (value == lower)
return FALSE;
else
st_adjustment_set_value (priv->hadjustment, value - step);
break;
case CLUTTER_SCROLL_RIGHT:
if (value == upper)
return FALSE;
else
st_adjustment_set_value (priv->hadjustment, value + step);
break;
}
return TRUE;
}
static void
st_scroll_view_class_init (StScrollViewClass *klass)
{
GParamSpec *pspec;
GObjectClass *object_class = G_OBJECT_CLASS (klass);
ClutterActorClass *actor_class = CLUTTER_ACTOR_CLASS (klass);
StWidgetClass *widget_class = ST_WIDGET_CLASS (klass);
g_type_class_add_private (klass, sizeof (StScrollViewPrivate));
object_class->get_property = st_scroll_view_get_property;
object_class->set_property = st_scroll_view_set_property;
object_class->dispose = st_scroll_view_dispose;
actor_class->paint = st_scroll_view_paint;
actor_class->pick = st_scroll_view_pick;
actor_class->get_preferred_width = st_scroll_view_get_preferred_width;
actor_class->get_preferred_height = st_scroll_view_get_preferred_height;
actor_class->allocate = st_scroll_view_allocate;
actor_class->scroll_event = st_scroll_view_scroll_event;
widget_class->style_changed = st_scroll_view_style_changed;
g_object_class_install_property (object_class,
PROP_HSCROLL,
g_param_spec_object ("hscroll",
"StScrollBar",
"Horizontal scroll indicator",
ST_TYPE_SCROLL_BAR,
G_PARAM_READABLE));
g_object_class_install_property (object_class,
PROP_VSCROLL,
g_param_spec_object ("vscroll",
"StScrollBar",
"Vertical scroll indicator",
ST_TYPE_SCROLL_BAR,
G_PARAM_READABLE));
pspec = g_param_spec_enum ("vscrollbar-policy",
"Vertical Scrollbar Policy",
"When the vertical scrollbar is displayed",
GTK_TYPE_POLICY_TYPE,
GTK_POLICY_AUTOMATIC,
G_PARAM_READWRITE);
g_object_class_install_property (object_class, PROP_VSCROLLBAR_POLICY, pspec);
pspec = g_param_spec_enum ("hscrollbar-policy",
"Horizontal Scrollbar Policy",
"When the horizontal scrollbar is displayed",
GTK_TYPE_POLICY_TYPE,
GTK_POLICY_AUTOMATIC,
G_PARAM_READWRITE);
g_object_class_install_property (object_class, PROP_HSCROLLBAR_POLICY, pspec);
pspec = g_param_spec_boolean ("hscrollbar-visible",
"Horizontal Scrollbar Visibility",
"Whether the horizontal scrollbar is visible",
TRUE,
G_PARAM_READABLE);
g_object_class_install_property (object_class, PROP_HSCROLLBAR_VISIBLE, pspec);
pspec = g_param_spec_boolean ("vscrollbar-visible",
"Vertical Scrollbar Visibility",
"Whether the vertical scrollbar is visible",
TRUE,
G_PARAM_READABLE);
g_object_class_install_property (object_class, PROP_VSCROLLBAR_VISIBLE, pspec);
pspec = g_param_spec_boolean ("enable-mouse-scrolling",
"Enable Mouse Scrolling",
"Enable automatic mouse wheel scrolling",
TRUE,
G_PARAM_READWRITE);
g_object_class_install_property (object_class,
PROP_MOUSE_SCROLL,
pspec);
}
static void
st_scroll_view_init (StScrollView *self)
{
StScrollViewPrivate *priv = self->priv = SCROLL_VIEW_PRIVATE (self);
priv->hscrollbar_policy = GTK_POLICY_AUTOMATIC;
priv->vscrollbar_policy = GTK_POLICY_AUTOMATIC;
priv->hadjustment = g_object_new (ST_TYPE_ADJUSTMENT, NULL);
priv->hscroll = g_object_new (ST_TYPE_SCROLL_BAR,
"adjustment", priv->hadjustment,
"vertical", FALSE,
NULL);
priv->vadjustment = g_object_new (ST_TYPE_ADJUSTMENT, NULL);
priv->vscroll = g_object_new (ST_TYPE_SCROLL_BAR,
"adjustment", priv->vadjustment,
"vertical", TRUE,
NULL);
clutter_actor_add_child (CLUTTER_ACTOR (self), priv->hscroll);
clutter_actor_add_child (CLUTTER_ACTOR (self), priv->vscroll);
/* mouse scroll is enabled by default, so we also need to be reactive */
priv->mouse_scroll = TRUE;
g_object_set (G_OBJECT (self), "reactive", TRUE, NULL);
}
static void
st_scroll_view_add (ClutterContainer *container,
ClutterActor *actor)
{
StScrollView *self = ST_SCROLL_VIEW (container);
StScrollViewPrivate *priv = self->priv;
if (ST_IS_SCROLLABLE (actor))
{
priv->child = actor;
/* chain up to StBin::add() */
st_scroll_view_parent_iface->add (container, actor);
st_scrollable_set_adjustments (ST_SCROLLABLE (actor),
priv->hadjustment, priv->vadjustment);
}
else
{
g_warning ("Attempting to add an actor of type %s to "
"a StScrollView, but the actor does "
"not implement StScrollable.",
g_type_name (G_OBJECT_TYPE (actor)));
}
}
static void
st_scroll_view_remove (ClutterContainer *container,
ClutterActor *actor)
{
StScrollView *self = ST_SCROLL_VIEW (container);
StScrollViewPrivate *priv = self->priv;
if (actor == priv->child)
{
g_object_ref (priv->child);
/* chain up to StBin::remove() */
st_scroll_view_parent_iface->remove (container, actor);
st_scrollable_set_adjustments (ST_SCROLLABLE (priv->child),
NULL, NULL);
g_object_unref (priv->child);
priv->child = NULL;
}
else
{
if (actor == priv->vscroll)
priv->vscroll = NULL;
else if (actor == priv->hscroll)
priv->hscroll = NULL;
else
g_assert ("Unknown child removed from StScrollView");
clutter_actor_remove_child (CLUTTER_ACTOR (container), actor);
}
}
static void
st_scroll_view_foreach_with_internals (ClutterContainer *container,
ClutterCallback callback,
gpointer user_data)
{
StScrollViewPrivate *priv = ST_SCROLL_VIEW (container)->priv;
if (priv->child != NULL)
callback (priv->child, user_data);
if (priv->hscroll != NULL)
callback (priv->hscroll, user_data);
if (priv->vscroll != NULL)
callback (priv->vscroll, user_data);
}
static void
clutter_container_iface_init (ClutterContainerIface *iface)
{
/* store a pointer to the StBin implementation of
* ClutterContainer so that we can chain up when
* overriding the methods
*/
st_scroll_view_parent_iface = g_type_interface_peek_parent (iface);
iface->add = st_scroll_view_add;
iface->remove = st_scroll_view_remove;
iface->foreach_with_internals = st_scroll_view_foreach_with_internals;
}
StWidget *
st_scroll_view_new (void)
{
return g_object_new (ST_TYPE_SCROLL_VIEW, NULL);
}
/**
* st_scroll_view_get_hscroll_bar:
* @scroll: a #StScrollView
*
* Gets the horizontal scrollbar of the scrollbiew
*
* Return value: (transfer none): the horizontal #StScrollBar
*/
ClutterActor *
st_scroll_view_get_hscroll_bar (StScrollView *scroll)
{
g_return_val_if_fail (ST_IS_SCROLL_VIEW (scroll), NULL);
return scroll->priv->hscroll;
}
/**
* st_scroll_view_get_vscroll_bar:
* @scroll: a #StScrollView
*
* Gets the vertical scrollbar of the scrollbiew
*
* Return value: (transfer none): the vertical #StScrollBar
*/
ClutterActor *
st_scroll_view_get_vscroll_bar (StScrollView *scroll)
{
g_return_val_if_fail (ST_IS_SCROLL_VIEW (scroll), NULL);
return scroll->priv->vscroll;
}
gfloat
st_scroll_view_get_column_size (StScrollView *scroll)
{
gdouble column_size;
g_return_val_if_fail (scroll, 0);
g_object_get (scroll->priv->hadjustment,
"step-increment", &column_size,
NULL);
return column_size;
}
void
st_scroll_view_set_column_size (StScrollView *scroll,
gfloat column_size)
{
g_return_if_fail (scroll);
if (column_size < 0)
{
scroll->priv->column_size_set = FALSE;
scroll->priv->column_size = -1;
}
else
{
scroll->priv->column_size_set = TRUE;
scroll->priv->column_size = column_size;
g_object_set (scroll->priv->hadjustment,
"step-increment", (gdouble) scroll->priv->column_size,
NULL);
}
}
gfloat
st_scroll_view_get_row_size (StScrollView *scroll)
{
gdouble row_size;
g_return_val_if_fail (scroll, 0);
g_object_get (scroll->priv->vadjustment,
"step-increment", &row_size,
NULL);
return row_size;
}
void
st_scroll_view_set_row_size (StScrollView *scroll,
gfloat row_size)
{
g_return_if_fail (scroll);
if (row_size < 0)
{
scroll->priv->row_size_set = FALSE;
scroll->priv->row_size = -1;
}
else
{
scroll->priv->row_size_set = TRUE;
scroll->priv->row_size = row_size;
g_object_set (scroll->priv->vadjustment,
"step-increment", (gdouble) scroll->priv->row_size,
NULL);
}
}
void
st_scroll_view_set_mouse_scrolling (StScrollView *scroll,
gboolean enabled)
{
StScrollViewPrivate *priv;
g_return_if_fail (ST_IS_SCROLL_VIEW (scroll));
priv = ST_SCROLL_VIEW (scroll)->priv;
if (priv->mouse_scroll != enabled)
{
priv->mouse_scroll = enabled;
/* make sure we can receive mouse wheel events */
if (enabled)
clutter_actor_set_reactive ((ClutterActor *) scroll, TRUE);
}
}
gboolean
st_scroll_view_get_mouse_scrolling (StScrollView *scroll)
{
StScrollViewPrivate *priv;
g_return_val_if_fail (ST_IS_SCROLL_VIEW (scroll), FALSE);
priv = ST_SCROLL_VIEW (scroll)->priv;
return priv->mouse_scroll;
}
/**
* st_scroll_view_set_policy:
* @scroll: A #StScrollView
* @hscroll: Whether to enable horizontal scrolling
* @vscroll: Whether to enable vertical scrolling
*
* Set the scroll policy.
*/
void
st_scroll_view_set_policy (StScrollView *scroll,
GtkPolicyType hscroll,
GtkPolicyType vscroll)
{
StScrollViewPrivate *priv;
g_return_if_fail (ST_IS_SCROLL_VIEW (scroll));
priv = ST_SCROLL_VIEW (scroll)->priv;
if (priv->hscrollbar_policy == hscroll && priv->vscrollbar_policy == vscroll)
return;
g_object_freeze_notify ((GObject *) scroll);
if (priv->hscrollbar_policy != hscroll)
{
priv->hscrollbar_policy = hscroll;
g_object_notify ((GObject *) scroll, "hscrollbar-policy");
}
if (priv->vscrollbar_policy != vscroll)
{
priv->vscrollbar_policy = vscroll;
g_object_notify ((GObject *) scroll, "vscrollbar-policy");
}
clutter_actor_queue_relayout (CLUTTER_ACTOR (scroll));
g_object_thaw_notify ((GObject *) scroll);
}