mutter/clutter/clutter-click-action.c
Lucas Rocha 03a713e18e click-action: don't use pointer grabs
The same behavior can be achieved by capturing events on stage while
button is pressed. This fixes a problem when using click and drag
actions on the same actor as there no grabs involved.

http://bugzilla.clutter-project.org/show_bug.cgi?id=2409
2010-11-11 23:18:20 +00:00

403 lines
10 KiB
C

/*
* Clutter.
*
* An OpenGL based 'interactive canvas' library.
*
* Copyright (C) 2010 Intel Corporation.
*
* 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, see <http://www.gnu.org/licenses/>.
*
* Author:
* Emmanuele Bassi <ebassi@linux.intel.com>
*/
/**
* SECTION:clutter-click-action
* @Title: ClutterClickAction
* @Short_Description: Action for clickable actors
*
* #ClutterClickAction is a sub-class of #ClutterAction that implements
* the logic for clickable actors, by using the low level events of
* #ClutterActor, such as #ClutterActor::button-press-event and
* #ClutterActor::button-release-event, to synthesize the high level
* #ClutterClickAction::clicked signal.
*
* To use #ClutterClickAction you just need to apply it to a #ClutterActor
* using clutter_actor_add_action() and connect to the
* #ClutterClickAction::clicked signal:
*
* |[
* ClutterAction *action = clutter_click_action_new ();
*
* clutter_actor_add_action (actor, action);
*
* g_signal_connect (action, "clicked", G_CALLBACK (on_clicked), NULL);
* ]|
*
* #ClutterClickAction is available since Clutter 1.4
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "clutter-click-action.h"
#include "clutter-debug.h"
#include "clutter-enum-types.h"
#include "clutter-marshal.h"
#include "clutter-private.h"
struct _ClutterClickActionPrivate
{
ClutterActor *stage;
guint event_id;
gulong capture_id;
guint press_button;
guint is_held : 1;
guint is_pressed : 1;
};
enum
{
PROP_0,
PROP_HELD,
PROP_PRESSED,
PROP_LAST
};
static GParamSpec *obj_props[PROP_LAST];
enum
{
CLICKED,
LAST_SIGNAL
};
static guint click_signals[LAST_SIGNAL] = { 0, };
G_DEFINE_TYPE (ClutterClickAction, clutter_click_action, CLUTTER_TYPE_ACTION);
/* forward declaration */
static gboolean on_captured_event (ClutterActor *stage,
ClutterEvent *event,
ClutterClickAction *action);
static inline void
click_action_set_pressed (ClutterClickAction *action,
gboolean is_pressed)
{
ClutterClickActionPrivate *priv = action->priv;
if (priv->is_pressed == is_pressed)
return;
priv->is_pressed = is_pressed;
_clutter_notify_by_pspec (G_OBJECT (action), obj_props[PROP_PRESSED]);
}
static gboolean
on_event (ClutterActor *actor,
ClutterEvent *event,
ClutterClickAction *action)
{
ClutterClickActionPrivate *priv = action->priv;
if (!clutter_actor_meta_get_enabled (CLUTTER_ACTOR_META (action)))
return FALSE;
switch (clutter_event_type (event))
{
case CLUTTER_BUTTON_PRESS:
if (clutter_event_get_click_count (event) != 1)
return FALSE;
if (priv->is_held)
return TRUE;
if (!clutter_actor_contains (actor, clutter_event_get_source (event)))
return FALSE;
priv->is_held = TRUE;
priv->press_button = clutter_event_get_button (event);
if (priv->stage == NULL)
priv->stage = clutter_actor_get_stage (actor);
priv->capture_id = g_signal_connect_after (priv->stage, "captured-event",
G_CALLBACK (on_captured_event),
action);
click_action_set_pressed (action, TRUE);
break;
case CLUTTER_ENTER:
click_action_set_pressed (action, priv->is_held);
break;
case CLUTTER_LEAVE:
click_action_set_pressed (action, priv->is_held);
break;
default:
break;
}
return FALSE;
}
static gboolean
on_captured_event (ClutterActor *stage,
ClutterEvent *event,
ClutterClickAction *action)
{
ClutterClickActionPrivate *priv = action->priv;
ClutterActor *actor;
actor = clutter_actor_meta_get_actor (CLUTTER_ACTOR_META (action));
switch (clutter_event_type (event))
{
case CLUTTER_BUTTON_RELEASE:
if (!priv->is_held)
return TRUE;
if (clutter_event_get_button (event) != priv->press_button ||
clutter_event_get_click_count (event) != 1)
return FALSE;
priv->is_held = FALSE;
/* disconnect the capture */
if (priv->capture_id != 0)
{
g_signal_handler_disconnect (priv->stage, priv->capture_id);
priv->capture_id = 0;
}
if (!clutter_actor_contains (actor, clutter_event_get_source (event)))
return FALSE;
click_action_set_pressed (action, FALSE);
g_signal_emit (action, click_signals[CLICKED], 0, actor);
break;
default:
break;
}
return FALSE;
}
static void
clutter_click_action_set_actor (ClutterActorMeta *meta,
ClutterActor *actor)
{
ClutterClickActionPrivate *priv = CLUTTER_CLICK_ACTION (meta)->priv;
if (priv->event_id != 0)
{
ClutterActor *old_actor = clutter_actor_meta_get_actor (meta);
g_signal_handler_disconnect (old_actor, priv->event_id);
priv->event_id = 0;
}
if (priv->capture_id != 0)
{
g_signal_handler_disconnect (priv->stage, priv->capture_id);
priv->capture_id = 0;
priv->stage = NULL;
}
if (actor != NULL)
priv->event_id = g_signal_connect (actor, "event",
G_CALLBACK (on_event),
meta);
CLUTTER_ACTOR_META_CLASS (clutter_click_action_parent_class)->set_actor (meta, actor);
}
static void
clutter_click_action_get_property (GObject *gobject,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
ClutterClickActionPrivate *priv = CLUTTER_CLICK_ACTION (gobject)->priv;
switch (prop_id)
{
case PROP_HELD:
g_value_set_boolean (value, priv->is_held);
break;
case PROP_PRESSED:
g_value_set_boolean (value, priv->is_pressed);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
break;
}
}
static void
clutter_click_action_class_init (ClutterClickActionClass *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
ClutterActorMetaClass *meta_class = CLUTTER_ACTOR_META_CLASS (klass);
g_type_class_add_private (klass, sizeof (ClutterClickActionPrivate));
meta_class->set_actor = clutter_click_action_set_actor;
gobject_class->get_property = clutter_click_action_get_property;
/**
* ClutterClickAction:pressed:
*
* Whether the clickable actor should be in "pressed" state
*
* Since: 1.4
*/
obj_props[PROP_PRESSED] =
g_param_spec_boolean ("pressed",
P_("Pressed"),
P_("Whether the clickable should be in pressed state"),
FALSE,
CLUTTER_PARAM_READABLE);
/**
* ClutterClickAction:held:
*
* Whether the clickable actor has the pointer grabbed
*
* Since: 1.4
*/
obj_props[PROP_HELD] =
g_param_spec_boolean ("held",
P_("Held"),
P_("Whether the clickable has a grab"),
FALSE,
CLUTTER_PARAM_READABLE);
_clutter_object_class_install_properties (gobject_class,
PROP_LAST,
obj_props);
/**
* ClutterClickAction::clicked:
* @action: the #ClutterClickAction that emitted the signal
* @actor: the #ClutterActor attached to the @action
*
* The ::clicked signal is emitted when the #ClutterActor to which
* a #ClutterClickAction has been applied should respond to a
* pointer button press and release events
*
* Since: 1.4
*/
click_signals[CLICKED] =
g_signal_new (I_("clicked"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (ClutterClickActionClass, clicked),
NULL, NULL,
_clutter_marshal_VOID__OBJECT,
G_TYPE_NONE, 1,
CLUTTER_TYPE_ACTOR);
}
static void
clutter_click_action_init (ClutterClickAction *self)
{
self->priv = G_TYPE_INSTANCE_GET_PRIVATE (self, CLUTTER_TYPE_CLICK_ACTION,
ClutterClickActionPrivate);
}
/**
* clutter_click_action_new:
*
* Creates a new #ClutterClickAction instance
*
* Return value: the newly created #ClutterClickAction
*
* Since: 1.4
*/
ClutterAction *
clutter_click_action_new (void)
{
return g_object_new (CLUTTER_TYPE_CLICK_ACTION, NULL);
}
/**
* clutter_click_action_release:
* @action: a #ClutterClickAction
*
* Emulates a release of the pointer button, which ungrabs the pointer
* and unsets the #ClutterClickAction:pressed state.
*
* This function is useful to break a grab, for instance after a certain
* amount of time has passed.
*
* Since: 1.4
*/
void
clutter_click_action_release (ClutterClickAction *action)
{
ClutterClickActionPrivate *priv;
g_return_if_fail (CLUTTER_IS_CLICK_ACTION (action));
priv = action->priv;
if (!priv->is_held)
return;
priv->is_held = FALSE;
/* disconnect the capture */
if (priv->capture_id != 0)
{
g_signal_handler_disconnect (priv->stage, priv->capture_id);
priv->capture_id = 0;
}
click_action_set_pressed (action, FALSE);
}
/**
* clutter_click_action_get_button:
* @action: a #ClutterClickAction
*
* Retrieves the button that was pressed.
*
* Return value: the button value
*
* Since: 1.4
*/
guint
clutter_click_action_get_button (ClutterClickAction *action)
{
g_return_val_if_fail (CLUTTER_IS_CLICK_ACTION (action), 0);
return action->priv->press_button;
}