mutter/clutter/clutter/clutter-layout-manager.c
Bilal Elmoussaoui a73ae93d59 clutter: Remove all the since annotations
Since they are all refer to the days clutter used to be a separate
library

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2441>
2022-08-02 09:52:22 +02:00

985 lines
32 KiB
C

/*
* Clutter.
*
* An OpenGL based 'interactive canvas' library.
*
* Copyright (C) 2009 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>
*/
/**
* ClutterLayoutManager:
*
* Layout managers base class
*
* #ClutterLayoutManager is a base abstract class for layout managers. A
* layout manager implements the layouting policy for a composite or a
* container actor: it controls the preferred size of the actor to which
* it has been paired, and it controls the allocation of its children.
*
* Any composite or container #ClutterActor subclass can delegate the
* layouting of its children to a #ClutterLayoutManager.
*
* Clutter provides some simple #ClutterLayoutManager sub-classes, like
* #ClutterFlowLayout and #ClutterBinLayout.
*
* ## Implementing a ClutterLayoutManager
* The implementation of a layout manager does not differ from the
* implementation of the size requisition and allocation bits of
* #ClutterActor, so you should read the relative documentation
* for subclassing #ClutterActor.
*
* The layout manager implementation can hold a back pointer to the
* #ClutterContainer by implementing the #ClutterLayoutManagerClass.set_container()
* virtual function. The layout manager should not hold a real reference (i.e.
* call g_object_ref()) on the container actor, to avoid reference cycles.
*
* If a layout manager has properties affecting the layout policies then it should
* emit the #ClutterLayoutManager::layout-changed signal on itself by using the
* clutter_layout_manager_layout_changed() function whenever one of these properties
* changes.
*
* ## Layout Properties
*
* If a layout manager has layout properties, that is properties that
* should exist only as the result of the presence of a specific (layout
* manager, container actor, child actor) combination, and it wishes to store
* those properties inside a #ClutterLayoutMeta, then it should override the
* #ClutterLayoutManagerClass.get_child_meta_type() virtual function to return
* the #GType of the #ClutterLayoutMeta sub-class used to store the layout
* properties; optionally, the #ClutterLayoutManager sub-class might also
* override the #ClutterLayoutManagerClass.create_child_meta() virtual function
* to control how the #ClutterLayoutMeta instance is created, otherwise the
* default implementation will be equivalent to:
*
* ```c
* ClutterLayoutManagerClass *klass;
* GType meta_type;
*
* klass = CLUTTER_LAYOUT_MANAGER_GET_CLASS (manager);
* meta_type = klass->get_child_meta_type (manager);
*
* return g_object_new (meta_type,
* "manager", manager,
* "container", container,
* "actor", actor,
* NULL);
* ```
*
* Where `manager` is the #ClutterLayoutManager, `container` is the
* #ClutterContainer using the #ClutterLayoutManager, and `actor` is
* the #ClutterActor child of the #ClutterContainer.
*
* ## Using ClutterLayoutManager with ClutterScript
*
* #ClutterLayoutManager instances can be created in the same way
* as other objects in #ClutterScript; properties can be set using the
* common syntax.
*
* Layout properties can be set on children of a container with
* a #ClutterLayoutManager using the `layout::` modifier on the property
* name, for instance:
*
* ```json
* {
* "type" : "ClutterActor",
* "layout-manager" : { "type" : "ClutterGridLayout" },
* "children" : [
* {
* "type" : "ClutterText",
* "text" : "Some text",
*
* "layout::row" : 0,
* "layout::column" : 0,
* "layout::x-align" : "left",
* "layout::y-align" : "center",
* "layout::x-expand" : true,
* "layout::y-expand" : true
* },
* {
* "type" : "ClutterText",
* "text" : "Some more text",
*
* "layout::row" : 0,
* "layout::column" : 1,
* "layout::x-align" : "right",
* "layout::y-align" : "center",
* "layout::x-expand" : true,
* "layout::y-expand" : true
* }
* ]
* }
* ```
*/
#include "clutter-build-config.h"
#include <glib-object.h>
#include <gobject/gvaluecollector.h>
#define CLUTTER_DISABLE_DEPRECATION_WARNINGS
#include "deprecated/clutter-container.h"
#include "clutter-debug.h"
#include "clutter-layout-manager.h"
#include "clutter-layout-meta.h"
#include "clutter-marshal.h"
#include "clutter-private.h"
#include "clutter-timeline.h"
#define LAYOUT_MANAGER_WARN_NOT_IMPLEMENTED(m,method) G_STMT_START { \
GObject *_obj = G_OBJECT (m); \
g_warning ("Layout managers of type %s do not implement " \
"the ClutterLayoutManager::%s method", \
G_OBJECT_TYPE_NAME (_obj), \
(method)); } G_STMT_END
enum
{
LAYOUT_CHANGED,
LAST_SIGNAL
};
G_DEFINE_ABSTRACT_TYPE (ClutterLayoutManager,
clutter_layout_manager,
G_TYPE_INITIALLY_UNOWNED)
static GQuark quark_layout_meta = 0;
static guint manager_signals[LAST_SIGNAL] = { 0, };
static void
layout_manager_freeze_layout_change (ClutterLayoutManager *manager)
{
gpointer is_frozen;
CLUTTER_NOTE (LAYOUT, "Freezing changes for manager '%s'[%p]",
G_OBJECT_TYPE_NAME (manager),
manager);
is_frozen = g_object_get_data (G_OBJECT (manager), "freeze-change");
if (is_frozen == NULL)
g_object_set_data (G_OBJECT (manager), "freeze-change",
GUINT_TO_POINTER (1));
else
{
guint level = GPOINTER_TO_UINT (is_frozen) + 1;
g_object_set_data (G_OBJECT (manager), "freeze-change",
GUINT_TO_POINTER (level));
}
}
static void
layout_manager_thaw_layout_change (ClutterLayoutManager *manager)
{
gpointer is_frozen;
is_frozen = g_object_get_data (G_OBJECT (manager), "freeze-change");
if (is_frozen == NULL)
g_critical (G_STRLOC ": Mismatched thaw; you have to call "
"clutter_layout_manager_freeze_layout_change() prior to "
"calling clutter_layout_manager_thaw_layout_change()");
else
{
guint level = GPOINTER_TO_UINT (is_frozen);
g_assert (level > 0);
CLUTTER_NOTE (LAYOUT, "Thawing changes for manager '%s'[%p]",
G_OBJECT_TYPE_NAME (manager),
manager);
level -= 1;
if (level == 0)
g_object_set_data (G_OBJECT (manager), "freeze-change", NULL);
else
g_object_set_data (G_OBJECT (manager), "freeze-change",
GUINT_TO_POINTER (level));
}
}
static void
layout_manager_real_get_preferred_width (ClutterLayoutManager *manager,
ClutterContainer *container,
gfloat for_height,
gfloat *min_width_p,
gfloat *nat_width_p)
{
LAYOUT_MANAGER_WARN_NOT_IMPLEMENTED (manager, "get_preferred_width");
if (min_width_p)
*min_width_p = 0.0;
if (nat_width_p)
*nat_width_p = 0.0;
}
static void
layout_manager_real_get_preferred_height (ClutterLayoutManager *manager,
ClutterContainer *container,
gfloat for_width,
gfloat *min_height_p,
gfloat *nat_height_p)
{
LAYOUT_MANAGER_WARN_NOT_IMPLEMENTED (manager, "get_preferred_height");
if (min_height_p)
*min_height_p = 0.0;
if (nat_height_p)
*nat_height_p = 0.0;
}
static void
layout_manager_real_allocate (ClutterLayoutManager *manager,
ClutterContainer *container,
const ClutterActorBox *allocation)
{
LAYOUT_MANAGER_WARN_NOT_IMPLEMENTED (manager, "allocate");
}
static void
layout_manager_real_set_container (ClutterLayoutManager *manager,
ClutterContainer *container)
{
if (container != NULL)
g_object_set_data (G_OBJECT (container), "clutter-layout-manager", manager);
}
static ClutterLayoutMeta *
layout_manager_real_create_child_meta (ClutterLayoutManager *manager,
ClutterContainer *container,
ClutterActor *actor)
{
ClutterLayoutManagerClass *klass;
GType meta_type;
klass = CLUTTER_LAYOUT_MANAGER_GET_CLASS (manager);
meta_type = klass->get_child_meta_type (manager);
/* provide a default implementation to reduce common code */
if (meta_type != G_TYPE_INVALID)
{
g_assert (g_type_is_a (meta_type, CLUTTER_TYPE_LAYOUT_META));
return g_object_new (meta_type,
"manager", manager,
"container", container,
"actor", actor,
NULL);
}
return NULL;
}
static GType
layout_manager_real_get_child_meta_type (ClutterLayoutManager *manager)
{
return G_TYPE_INVALID;
}
static void
clutter_layout_manager_class_init (ClutterLayoutManagerClass *klass)
{
quark_layout_meta =
g_quark_from_static_string ("clutter-layout-manager-child-meta");
klass->get_preferred_width = layout_manager_real_get_preferred_width;
klass->get_preferred_height = layout_manager_real_get_preferred_height;
klass->allocate = layout_manager_real_allocate;
klass->create_child_meta = layout_manager_real_create_child_meta;
klass->get_child_meta_type = layout_manager_real_get_child_meta_type;
/* XXX:2.0 - Remove */
klass->set_container = layout_manager_real_set_container;
/**
* ClutterLayoutManager::layout-changed:
* @manager: the #ClutterLayoutManager that emitted the signal
*
* The signal is emitted each time a layout manager
* has been changed. Every #ClutterActor using the @manager instance
* as a layout manager should connect a handler to the
* [signal@LayoutManager::layout-changed]
* signal and queue a relayout on themselves:
*
* ```c
* static void layout_changed (ClutterLayoutManager *manager,
* ClutterActor *self)
* {
* clutter_actor_queue_relayout (self);
* }
* ...
* self->manager = g_object_ref_sink (manager);
* g_signal_connect (self->manager, "layout-changed",
* G_CALLBACK (layout_changed),
* self);
* ```
*
* Sub-classes of #ClutterLayoutManager that implement a layout that
* can be controlled or changed using parameters should emit the
* ::layout-changed signal whenever one of the parameters changes,
* by using clutter_layout_manager_layout_changed().
*/
manager_signals[LAYOUT_CHANGED] =
g_signal_new (I_("layout-changed"),
G_TYPE_FROM_CLASS (klass),
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (ClutterLayoutManagerClass,
layout_changed),
NULL, NULL, NULL,
G_TYPE_NONE, 0);
}
static void
clutter_layout_manager_init (ClutterLayoutManager *manager)
{
}
/**
* clutter_layout_manager_get_preferred_width:
* @manager: a #ClutterLayoutManager
* @container: the #ClutterContainer using @manager
* @for_height: the height for which the width should be computed, or -1
* @min_width_p: (out) (allow-none): return location for the minimum width
* of the layout, or %NULL
* @nat_width_p: (out) (allow-none): return location for the natural width
* of the layout, or %NULL
*
* Computes the minimum and natural widths of the @container according
* to @manager.
*
* See also clutter_actor_get_preferred_width()
*/
void
clutter_layout_manager_get_preferred_width (ClutterLayoutManager *manager,
ClutterContainer *container,
gfloat for_height,
gfloat *min_width_p,
gfloat *nat_width_p)
{
ClutterLayoutManagerClass *klass;
g_return_if_fail (CLUTTER_IS_LAYOUT_MANAGER (manager));
g_return_if_fail (CLUTTER_IS_CONTAINER (container));
klass = CLUTTER_LAYOUT_MANAGER_GET_CLASS (manager);
klass->get_preferred_width (manager, container, for_height,
min_width_p,
nat_width_p);
}
/**
* clutter_layout_manager_get_preferred_height:
* @manager: a #ClutterLayoutManager
* @container: the #ClutterContainer using @manager
* @for_width: the width for which the height should be computed, or -1
* @min_height_p: (out) (allow-none): return location for the minimum height
* of the layout, or %NULL
* @nat_height_p: (out) (allow-none): return location for the natural height
* of the layout, or %NULL
*
* Computes the minimum and natural heights of the @container according
* to @manager.
*
* See also clutter_actor_get_preferred_height()
*/
void
clutter_layout_manager_get_preferred_height (ClutterLayoutManager *manager,
ClutterContainer *container,
gfloat for_width,
gfloat *min_height_p,
gfloat *nat_height_p)
{
ClutterLayoutManagerClass *klass;
g_return_if_fail (CLUTTER_IS_LAYOUT_MANAGER (manager));
g_return_if_fail (CLUTTER_IS_CONTAINER (container));
klass = CLUTTER_LAYOUT_MANAGER_GET_CLASS (manager);
klass->get_preferred_height (manager, container, for_width,
min_height_p,
nat_height_p);
}
/**
* clutter_layout_manager_allocate:
* @manager: a #ClutterLayoutManager
* @container: the #ClutterContainer using @manager
* @allocation: the #ClutterActorBox containing the allocated area
* of @container
*
* Allocates the children of @container given an area
*
* See also clutter_actor_allocate()
*/
void
clutter_layout_manager_allocate (ClutterLayoutManager *manager,
ClutterContainer *container,
const ClutterActorBox *allocation)
{
ClutterLayoutManagerClass *klass;
g_return_if_fail (CLUTTER_IS_LAYOUT_MANAGER (manager));
g_return_if_fail (CLUTTER_IS_CONTAINER (container));
g_return_if_fail (allocation != NULL);
klass = CLUTTER_LAYOUT_MANAGER_GET_CLASS (manager);
klass->allocate (manager, container, allocation);
}
/**
* clutter_layout_manager_layout_changed:
* @manager: a #ClutterLayoutManager
*
* Emits the #ClutterLayoutManager::layout-changed signal on @manager
*
* This function should only be called by implementations of the
* #ClutterLayoutManager class
*/
void
clutter_layout_manager_layout_changed (ClutterLayoutManager *manager)
{
gpointer is_frozen;
g_return_if_fail (CLUTTER_IS_LAYOUT_MANAGER (manager));
is_frozen = g_object_get_data (G_OBJECT (manager), "freeze-change");
if (is_frozen == NULL)
g_signal_emit (manager, manager_signals[LAYOUT_CHANGED], 0);
else
CLUTTER_NOTE (LAYOUT, "Layout manager '%s'[%p] has been frozen",
G_OBJECT_TYPE_NAME (manager),
manager);
}
/**
* clutter_layout_manager_set_container:
* @manager: a #ClutterLayoutManager
* @container: (allow-none): a #ClutterContainer using @manager
*
* If the #ClutterLayoutManager sub-class allows it, allow
* adding a weak reference of the @container using @manager
* from within the layout manager
*
* The layout manager should not increase the reference
* count of the @container
*/
void
clutter_layout_manager_set_container (ClutterLayoutManager *manager,
ClutterContainer *container)
{
ClutterLayoutManagerClass *klass;
g_return_if_fail (CLUTTER_IS_LAYOUT_MANAGER (manager));
g_return_if_fail (container == NULL || CLUTTER_IS_CONTAINER (container));
klass = CLUTTER_LAYOUT_MANAGER_GET_CLASS (manager);
if (klass->set_container)
klass->set_container (manager, container);
}
GType
_clutter_layout_manager_get_child_meta_type (ClutterLayoutManager *manager)
{
return CLUTTER_LAYOUT_MANAGER_GET_CLASS (manager)->get_child_meta_type (manager);
}
static inline ClutterLayoutMeta *
create_child_meta (ClutterLayoutManager *manager,
ClutterContainer *container,
ClutterActor *actor)
{
ClutterLayoutManagerClass *klass;
ClutterLayoutMeta *meta = NULL;
layout_manager_freeze_layout_change (manager);
klass = CLUTTER_LAYOUT_MANAGER_GET_CLASS (manager);
if (klass->get_child_meta_type (manager) != G_TYPE_INVALID)
meta = klass->create_child_meta (manager, container, actor);
layout_manager_thaw_layout_change (manager);
return meta;
}
static inline ClutterLayoutMeta *
get_child_meta (ClutterLayoutManager *manager,
ClutterContainer *container,
ClutterActor *actor)
{
ClutterLayoutMeta *layout = NULL;
layout = g_object_get_qdata (G_OBJECT (actor), quark_layout_meta);
if (layout != NULL)
{
ClutterChildMeta *child = CLUTTER_CHILD_META (layout);
if (layout->manager == manager &&
child->container == container &&
child->actor == actor)
return layout;
/* if the LayoutMeta referenced is not attached to the
* layout manager then we simply ask the layout manager
* to replace it with the right one
*/
}
layout = create_child_meta (manager, container, actor);
if (layout != NULL)
{
g_assert (CLUTTER_IS_LAYOUT_META (layout));
g_object_set_qdata_full (G_OBJECT (actor), quark_layout_meta,
layout,
(GDestroyNotify) g_object_unref);
return layout;
}
return NULL;
}
/**
* clutter_layout_manager_get_child_meta:
* @manager: a #ClutterLayoutManager
* @container: a #ClutterContainer using @manager
* @actor: a #ClutterActor child of @container
*
* Retrieves the #ClutterLayoutMeta that the layout @manager associated
* to the @actor child of @container, eventually by creating one if the
* #ClutterLayoutManager supports layout properties
*
* Return value: (transfer none): a #ClutterLayoutMeta, or %NULL if the
* #ClutterLayoutManager does not have layout properties. The returned
* layout meta instance is owned by the #ClutterLayoutManager and it
* should not be unreferenced
*/
ClutterLayoutMeta *
clutter_layout_manager_get_child_meta (ClutterLayoutManager *manager,
ClutterContainer *container,
ClutterActor *actor)
{
g_return_val_if_fail (CLUTTER_IS_LAYOUT_MANAGER (manager), NULL);
g_return_val_if_fail (CLUTTER_IS_CONTAINER (container), NULL);
g_return_val_if_fail (CLUTTER_IS_ACTOR (actor), NULL);
return get_child_meta (manager, container, actor);
}
static inline gboolean
layout_set_property_internal (ClutterLayoutManager *manager,
GObject *gobject,
GParamSpec *pspec,
const GValue *value)
{
if (pspec->flags & G_PARAM_CONSTRUCT_ONLY)
{
g_warning ("%s: Child property '%s' of the layout manager of "
"type '%s' is constructor-only",
G_STRLOC, pspec->name, G_OBJECT_TYPE_NAME (manager));
return FALSE;
}
if (!(pspec->flags & G_PARAM_WRITABLE))
{
g_warning ("%s: Child property '%s' of the layout manager of "
"type '%s' is not writable",
G_STRLOC, pspec->name, G_OBJECT_TYPE_NAME (manager));
return FALSE;
}
g_object_set_property (gobject, pspec->name, value);
return TRUE;
}
static inline gboolean
layout_get_property_internal (ClutterLayoutManager *manager,
GObject *gobject,
GParamSpec *pspec,
GValue *value)
{
if (!(pspec->flags & G_PARAM_READABLE))
{
g_warning ("%s: Child property '%s' of the layout manager of "
"type '%s' is not readable",
G_STRLOC, pspec->name, G_OBJECT_TYPE_NAME (manager));
return FALSE;
}
g_object_get_property (gobject, pspec->name, value);
return TRUE;
}
/**
* clutter_layout_manager_child_set:
* @manager: a #ClutterLayoutManager
* @container: a #ClutterContainer using @manager
* @actor: a #ClutterActor child of @container
* @first_property: the first property name
* @...: a list of property name and value pairs
*
* Sets a list of properties and their values on the #ClutterLayoutMeta
* associated by @manager to a child of @container
*
* Languages bindings should use clutter_layout_manager_child_set_property()
* instead
*/
void
clutter_layout_manager_child_set (ClutterLayoutManager *manager,
ClutterContainer *container,
ClutterActor *actor,
const gchar *first_property,
...)
{
ClutterLayoutMeta *meta;
GObjectClass *klass;
const gchar *pname;
va_list var_args;
g_return_if_fail (CLUTTER_IS_LAYOUT_MANAGER (manager));
g_return_if_fail (CLUTTER_IS_CONTAINER (container));
g_return_if_fail (CLUTTER_IS_ACTOR (actor));
g_return_if_fail (first_property != NULL);
meta = get_child_meta (manager, container, actor);
if (meta == NULL)
{
g_warning ("Layout managers of type '%s' do not support "
"layout metadata",
g_type_name (G_OBJECT_TYPE (manager)));
return;
}
klass = G_OBJECT_GET_CLASS (meta);
va_start (var_args, first_property);
pname = first_property;
while (pname)
{
GValue value = G_VALUE_INIT;
GParamSpec *pspec;
gchar *error;
gboolean res;
pspec = g_object_class_find_property (klass, pname);
if (pspec == NULL)
{
g_warning ("%s: Layout managers of type '%s' have no layout "
"property named '%s'",
G_STRLOC, G_OBJECT_TYPE_NAME (manager), pname);
break;
}
G_VALUE_COLLECT_INIT (&value, G_PARAM_SPEC_VALUE_TYPE (pspec),
var_args, 0,
&error);
if (error)
{
g_warning ("%s: %s", G_STRLOC, error);
g_free (error);
break;
}
res = layout_set_property_internal (manager, G_OBJECT (meta),
pspec,
&value);
g_value_unset (&value);
if (!res)
break;
pname = va_arg (var_args, gchar*);
}
va_end (var_args);
}
/**
* clutter_layout_manager_child_set_property:
* @manager: a #ClutterLayoutManager
* @container: a #ClutterContainer using @manager
* @actor: a #ClutterActor child of @container
* @property_name: the name of the property to set
* @value: a #GValue with the value of the property to set
*
* Sets a property on the #ClutterLayoutMeta created by @manager and
* attached to a child of @container
*/
void
clutter_layout_manager_child_set_property (ClutterLayoutManager *manager,
ClutterContainer *container,
ClutterActor *actor,
const gchar *property_name,
const GValue *value)
{
ClutterLayoutMeta *meta;
GObjectClass *klass;
GParamSpec *pspec;
g_return_if_fail (CLUTTER_IS_LAYOUT_MANAGER (manager));
g_return_if_fail (CLUTTER_IS_CONTAINER (container));
g_return_if_fail (CLUTTER_IS_ACTOR (actor));
g_return_if_fail (property_name != NULL);
g_return_if_fail (value != NULL);
meta = get_child_meta (manager, container, actor);
if (meta == NULL)
{
g_warning ("Layout managers of type '%s' do not support "
"layout metadata",
g_type_name (G_OBJECT_TYPE (manager)));
return;
}
klass = G_OBJECT_GET_CLASS (meta);
pspec = g_object_class_find_property (klass, property_name);
if (pspec == NULL)
{
g_warning ("%s: Layout managers of type '%s' have no layout "
"property named '%s'",
G_STRLOC, G_OBJECT_TYPE_NAME (manager), property_name);
return;
}
layout_set_property_internal (manager, G_OBJECT (meta), pspec, value);
}
/**
* clutter_layout_manager_child_get:
* @manager: a #ClutterLayoutManager
* @container: a #ClutterContainer using @manager
* @actor: a #ClutterActor child of @container
* @first_property: the name of the first property
* @...: a list of property name and return location for the value pairs
*
* Retrieves the values for a list of properties out of the
* #ClutterLayoutMeta created by @manager and attached to the
* child of a @container
*/
void
clutter_layout_manager_child_get (ClutterLayoutManager *manager,
ClutterContainer *container,
ClutterActor *actor,
const gchar *first_property,
...)
{
ClutterLayoutMeta *meta;
GObjectClass *klass;
const gchar *pname;
va_list var_args;
g_return_if_fail (CLUTTER_IS_LAYOUT_MANAGER (manager));
g_return_if_fail (CLUTTER_IS_CONTAINER (container));
g_return_if_fail (CLUTTER_IS_ACTOR (actor));
g_return_if_fail (first_property != NULL);
meta = get_child_meta (manager, container, actor);
if (meta == NULL)
{
g_warning ("Layout managers of type '%s' do not support "
"layout metadata",
g_type_name (G_OBJECT_TYPE (manager)));
return;
}
klass = G_OBJECT_GET_CLASS (meta);
va_start (var_args, first_property);
pname = first_property;
while (pname)
{
GValue value = G_VALUE_INIT;
GParamSpec *pspec;
gchar *error;
gboolean res;
pspec = g_object_class_find_property (klass, pname);
if (pspec == NULL)
{
g_warning ("%s: Layout managers of type '%s' have no layout "
"property named '%s'",
G_STRLOC, G_OBJECT_TYPE_NAME (manager), pname);
break;
}
g_value_init (&value, G_PARAM_SPEC_VALUE_TYPE (pspec));
res = layout_get_property_internal (manager, G_OBJECT (meta),
pspec,
&value);
if (!res)
{
g_value_unset (&value);
break;
}
G_VALUE_LCOPY (&value, var_args, 0, &error);
if (error)
{
g_warning ("%s: %s", G_STRLOC, error);
g_free (error);
g_value_unset (&value);
break;
}
g_value_unset (&value);
pname = va_arg (var_args, gchar*);
}
va_end (var_args);
}
/**
* clutter_layout_manager_child_get_property:
* @manager: a #ClutterLayoutManager
* @container: a #ClutterContainer using @manager
* @actor: a #ClutterActor child of @container
* @property_name: the name of the property to get
* @value: a #GValue with the value of the property to get
*
* Gets a property on the #ClutterLayoutMeta created by @manager and
* attached to a child of @container
*
* The #GValue must already be initialized to the type of the property
* and has to be unset with g_value_unset() after extracting the real
* value out of it
*/
void
clutter_layout_manager_child_get_property (ClutterLayoutManager *manager,
ClutterContainer *container,
ClutterActor *actor,
const gchar *property_name,
GValue *value)
{
ClutterLayoutMeta *meta;
GObjectClass *klass;
GParamSpec *pspec;
g_return_if_fail (CLUTTER_IS_LAYOUT_MANAGER (manager));
g_return_if_fail (CLUTTER_IS_CONTAINER (container));
g_return_if_fail (CLUTTER_IS_ACTOR (actor));
g_return_if_fail (property_name != NULL);
g_return_if_fail (value != NULL);
meta = get_child_meta (manager, container, actor);
if (meta == NULL)
{
g_warning ("Layout managers of type %s do not support "
"layout metadata",
g_type_name (G_OBJECT_TYPE (manager)));
return;
}
klass = G_OBJECT_GET_CLASS (meta);
pspec = g_object_class_find_property (klass, property_name);
if (pspec == NULL)
{
g_warning ("%s: Layout managers of type '%s' have no layout "
"property named '%s'",
G_STRLOC, G_OBJECT_TYPE_NAME (manager), property_name);
return;
}
layout_get_property_internal (manager, G_OBJECT (meta), pspec, value);
}
/**
* clutter_layout_manager_find_child_property:
* @manager: a #ClutterLayoutManager
* @name: the name of the property
*
* Retrieves the #GParamSpec for the layout property @name inside
* the #ClutterLayoutMeta sub-class used by @manager
*
* Return value: (transfer none): a #GParamSpec describing the property,
* or %NULL if no property with that name exists. The returned
* #GParamSpec is owned by the layout manager and should not be
* modified or freed
*/
GParamSpec *
clutter_layout_manager_find_child_property (ClutterLayoutManager *manager,
const gchar *name)
{
ClutterLayoutManagerClass *klass;
GObjectClass *meta_klass;
GParamSpec *pspec;
GType meta_type;
klass = CLUTTER_LAYOUT_MANAGER_GET_CLASS (manager);
meta_type = klass->get_child_meta_type (manager);
if (meta_type == G_TYPE_INVALID)
return NULL;
meta_klass = g_type_class_ref (meta_type);
pspec = g_object_class_find_property (meta_klass, name);
g_type_class_unref (meta_klass);
return pspec;
}
/**
* clutter_layout_manager_list_child_properties:
* @manager: a #ClutterLayoutManager
* @n_pspecs: (out): return location for the number of returned
* `GParamSpec`s
*
* Retrieves all the `GParamSpec`s for the layout properties
* stored inside the #ClutterLayoutMeta sub-class used by @manager
*
* Return value: (transfer full) (array length=n_pspecs): the newly-allocated,
* %NULL-terminated array of `GParamSpec`s. Use g_free() to free the
* resources allocated for the array
*/
GParamSpec **
clutter_layout_manager_list_child_properties (ClutterLayoutManager *manager,
guint *n_pspecs)
{
ClutterLayoutManagerClass *klass;
GObjectClass *meta_klass;
GParamSpec **pspecs;
GType meta_type;
klass = CLUTTER_LAYOUT_MANAGER_GET_CLASS (manager);
meta_type = klass->get_child_meta_type (manager);
if (meta_type == G_TYPE_INVALID)
return NULL;
meta_klass = g_type_class_ref (meta_type);
pspecs = g_object_class_list_properties (meta_klass, n_pspecs);
g_type_class_unref (meta_klass);
return pspecs;
}