Learning_GTK4_tree/gtk/gtkeventcontrollermotion.c

336 lines
10 KiB
C

/* GTK - The GIMP Toolkit
* Copyright (C) 2017, Red Hat, Inc.
*
* 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(s): Matthias Clasen <mclasen@redhat.com>
*/
/**
* GtkEventControllerMotion:
*
* `GtkEventControllerMotion` is an event controller tracking the pointer
* position.
*
* The event controller offers [signal@Gtk.EventControllerMotion::enter]
* and [signal@Gtk.EventControllerMotion::leave] signals, as well as
* [property@Gtk.EventControllerMotion:is-pointer] and
* [property@Gtk.EventControllerMotion:contains-pointer] properties
* which are updated to reflect changes in the pointer position as it
* moves over the widget.
*/
#include "config.h"
#include "gtkprivate.h"
#include "gtkwidgetprivate.h"
#include "gtkmarshalers.h"
#include "gtkeventcontrollerprivate.h"
#include "gtkeventcontrollermotion.h"
#include "gtktypebuiltins.h"
#include "gtkmarshalers.h"
struct _GtkEventControllerMotion
{
GtkEventController parent_instance;
guint is_pointer : 1;
guint contains_pointer : 1;
};
struct _GtkEventControllerMotionClass
{
GtkEventControllerClass parent_class;
};
enum {
ENTER,
LEAVE,
MOTION,
N_SIGNALS
};
enum {
PROP_IS_POINTER = 1,
PROP_CONTAINS_POINTER,
NUM_PROPERTIES
};
static GParamSpec *props[NUM_PROPERTIES] = { NULL, };
static guint signals[N_SIGNALS] = { 0 };
G_DEFINE_TYPE (GtkEventControllerMotion, gtk_event_controller_motion, GTK_TYPE_EVENT_CONTROLLER)
static gboolean
gtk_event_controller_motion_handle_event (GtkEventController *controller,
GdkEvent *event,
double x,
double y)
{
GtkEventControllerClass *parent_class;
GdkEventType type;
type = gdk_event_get_event_type (event);
if (type == GDK_MOTION_NOTIFY)
g_signal_emit (controller, signals[MOTION], 0, x, y);
parent_class = GTK_EVENT_CONTROLLER_CLASS (gtk_event_controller_motion_parent_class);
return parent_class->handle_event (controller, event, x, y);
}
static void
update_pointer_focus (GtkEventController *controller,
const GtkCrossingData *crossing,
double x,
double y)
{
GtkEventControllerMotion *motion = GTK_EVENT_CONTROLLER_MOTION (controller);
GtkWidget *widget = gtk_event_controller_get_widget (controller);
gboolean is_pointer = FALSE;
gboolean contains_pointer = FALSE;
gboolean enter = FALSE;
gboolean leave = FALSE;
if (crossing->direction == GTK_CROSSING_IN)
{
if (crossing->new_descendent != NULL)
{
contains_pointer = TRUE;
}
if (crossing->new_target == widget)
{
contains_pointer = TRUE;
is_pointer = TRUE;
}
}
else
{
if (crossing->new_descendent != NULL ||
crossing->new_target == widget)
contains_pointer = TRUE;
is_pointer = FALSE;
}
if (motion->contains_pointer != contains_pointer)
{
enter = contains_pointer;
leave = !contains_pointer;
}
if (leave)
g_signal_emit (controller, signals[LEAVE], 0);
g_object_freeze_notify (G_OBJECT (motion));
if (motion->is_pointer != is_pointer)
{
motion->is_pointer = is_pointer;
g_object_notify_by_pspec (G_OBJECT (motion), props[PROP_IS_POINTER]);
}
if (motion->contains_pointer != contains_pointer)
{
motion->contains_pointer = contains_pointer;
g_object_notify_by_pspec (G_OBJECT (motion), props[PROP_CONTAINS_POINTER]);
}
g_object_thaw_notify (G_OBJECT (motion));
if (enter)
g_signal_emit (controller, signals[ENTER], 0, x, y);
}
static void
gtk_event_controller_motion_handle_crossing (GtkEventController *controller,
const GtkCrossingData *crossing,
double x,
double y)
{
if (crossing->type == GTK_CROSSING_POINTER)
update_pointer_focus (controller, crossing, x, y);
}
static void
gtk_event_controller_motion_get_property (GObject *object,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
GtkEventControllerMotion *controller = GTK_EVENT_CONTROLLER_MOTION (object);
switch (prop_id)
{
case PROP_IS_POINTER:
g_value_set_boolean (value, controller->is_pointer);
break;
case PROP_CONTAINS_POINTER:
g_value_set_boolean (value, controller->contains_pointer);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
}
}
static void
gtk_event_controller_motion_class_init (GtkEventControllerMotionClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
GtkEventControllerClass *controller_class = GTK_EVENT_CONTROLLER_CLASS (klass);
object_class->get_property = gtk_event_controller_motion_get_property;
controller_class->handle_event = gtk_event_controller_motion_handle_event;
controller_class->handle_crossing = gtk_event_controller_motion_handle_crossing;
/**
* GtkEventControllerMotion:is-pointer: (attributes org.gtk.Property.get=gtk_event_controller_motion_is_pointer)
*
* Whether the pointer is in the controllers widget itself,
* as opposed to in a descendent widget.
*
* See also [property@Gtk.EventControllerMotion:contains-pointer].
*
* When handling crossing events, this property is updated
* before [signal@Gtk.EventControllerMotion::enter], but after
* [signal@Gtk.EventControllerMotion::leave] is emitted.
*/
props[PROP_IS_POINTER] =
g_param_spec_boolean ("is-pointer", NULL, NULL,
FALSE,
G_PARAM_READABLE);
/**
* GtkEventControllerMotion:contains-pointer: (attributes org.gtk.Property.get=gtk_event_controller_motion_contains_pointer)
*
* Whether the pointer is in the controllers widget or a descendant.
*
* See also [property@Gtk.EventControllerMotion:is-pointer].
*
* When handling crossing events, this property is updated
* before [signal@Gtk.EventControllerMotion::enter], but after
* [signal@Gtk.EventControllerMotion::leave] is emitted.
*/
props[PROP_CONTAINS_POINTER] =
g_param_spec_boolean ("contains-pointer", NULL, NULL,
FALSE,
G_PARAM_READABLE);
g_object_class_install_properties (object_class, NUM_PROPERTIES, props);
/**
* GtkEventControllerMotion::enter:
* @controller: the object which received the signal
* @x: coordinates of pointer location
* @y: coordinates of pointer location
*
* Signals that the pointer has entered the widget.
*/
signals[ENTER] =
g_signal_new (I_("enter"),
GTK_TYPE_EVENT_CONTROLLER_MOTION,
G_SIGNAL_RUN_LAST,
0, NULL, NULL,
_gtk_marshal_VOID__DOUBLE_DOUBLE,
G_TYPE_NONE, 2,
G_TYPE_DOUBLE,
G_TYPE_DOUBLE);
g_signal_set_va_marshaller (signals[ENTER],
G_TYPE_FROM_CLASS (klass),
_gtk_marshal_VOID__DOUBLE_DOUBLEv);
/**
* GtkEventControllerMotion::leave:
* @controller: the object which received the signal
*
* Signals that the pointer has left the widget.
*/
signals[LEAVE] =
g_signal_new (I_("leave"),
GTK_TYPE_EVENT_CONTROLLER_MOTION,
G_SIGNAL_RUN_LAST,
0, NULL, NULL,
NULL,
G_TYPE_NONE, 0);
/**
* GtkEventControllerMotion::motion:
* @controller: The object that received the signal
* @x: the x coordinate
* @y: the y coordinate
*
* Emitted when the pointer moves inside the widget.
*/
signals[MOTION] =
g_signal_new (I_("motion"),
GTK_TYPE_EVENT_CONTROLLER_MOTION,
G_SIGNAL_RUN_FIRST,
0, NULL, NULL,
_gtk_marshal_VOID__DOUBLE_DOUBLE,
G_TYPE_NONE, 2, G_TYPE_DOUBLE, G_TYPE_DOUBLE);
g_signal_set_va_marshaller (signals[MOTION],
GTK_TYPE_EVENT_CONTROLLER_MOTION,
_gtk_marshal_VOID__DOUBLE_DOUBLEv);
}
static void
gtk_event_controller_motion_init (GtkEventControllerMotion *motion)
{
}
/**
* gtk_event_controller_motion_new:
*
* Creates a new event controller that will handle motion events.
*
* Returns: a new `GtkEventControllerMotion`
**/
GtkEventController *
gtk_event_controller_motion_new (void)
{
return g_object_new (GTK_TYPE_EVENT_CONTROLLER_MOTION,
NULL);
}
/**
* gtk_event_controller_motion_contains_pointer: (attributes org.gtk.Method.get_property=contains-pointer)
* @self: a `GtkEventControllerMotion`
*
* Returns if a pointer is within @self or one of its children.
*
* Returns: %TRUE if a pointer is within @self or one of its children
*/
gboolean
gtk_event_controller_motion_contains_pointer (GtkEventControllerMotion *self)
{
g_return_val_if_fail (GTK_IS_EVENT_CONTROLLER_MOTION (self), FALSE);
return self->contains_pointer;
}
/**
* gtk_event_controller_motion_is_pointer: (attributes org.gtk.Method.get_property=is-pointer)
* @self: a `GtkEventControllerMotion`
*
* Returns if a pointer is within @self, but not one of its children.
*
* Returns: %TRUE if a pointer is within @self but not one of its children
*/
gboolean
gtk_event_controller_motion_is_pointer (GtkEventControllerMotion *self)
{
g_return_val_if_fail (GTK_IS_EVENT_CONTROLLER_MOTION (self), FALSE);
return self->is_pointer;
}