gtk2/gtk/gtkatcontext.c
2020-07-30 09:06:49 +02:00

625 lines
20 KiB
C

/* gtkatcontext.c: Assistive technology context
*
* Copyright 2020 GNOME Foundation
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*
* 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 2.1 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/>.
*/
/**
* SECTION:gtkatcontext
* @Title: GtkATContext
* @Short_description: An object communicating to Assistive Technologies
*
* GtkATContext is an abstract class provided by GTK to communicate to
* platform-specific assistive technologies API.
*
* Each platform supported by GTK implements a #GtkATContext subclass, and
* is responsible for updating the accessible state in response to state
* changes in #GtkAccessible.
*/
#include "config.h"
#include "gtkatcontextprivate.h"
#include "gtkaccessiblevalueprivate.h"
#include "gtktestatcontextprivate.h"
#include "gtktypebuiltins.h"
G_DEFINE_ABSTRACT_TYPE (GtkATContext, gtk_at_context, G_TYPE_OBJECT)
enum
{
PROP_ACCESSIBLE_ROLE = 1,
PROP_ACCESSIBLE,
N_PROPS
};
enum
{
STATE_CHANGE,
LAST_SIGNAL
};
static GParamSpec *obj_props[N_PROPS];
static guint obj_signals[LAST_SIGNAL];
static void
gtk_at_context_finalize (GObject *gobject)
{
GtkATContext *self = GTK_AT_CONTEXT (gobject);
gtk_accessible_attribute_set_unref (self->properties);
gtk_accessible_attribute_set_unref (self->relations);
gtk_accessible_attribute_set_unref (self->states);
G_OBJECT_CLASS (gtk_at_context_parent_class)->finalize (gobject);
}
static void
gtk_at_context_set_property (GObject *gobject,
guint prop_id,
const GValue *value,
GParamSpec *pspec)
{
GtkATContext *self = GTK_AT_CONTEXT (gobject);
switch (prop_id)
{
case PROP_ACCESSIBLE_ROLE:
self->accessible_role = g_value_get_enum (value);
break;
case PROP_ACCESSIBLE:
self->accessible = g_value_get_object (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
}
}
static void
gtk_at_context_get_property (GObject *gobject,
guint prop_id,
GValue *value,
GParamSpec *pspec)
{
GtkATContext *self = GTK_AT_CONTEXT (gobject);
switch (prop_id)
{
case PROP_ACCESSIBLE_ROLE:
g_value_set_enum (value, self->accessible_role);
break;
case PROP_ACCESSIBLE:
g_value_set_object (value, self->accessible);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, prop_id, pspec);
}
}
static void
gtk_at_context_real_state_change (GtkATContext *self,
GtkAccessibleStateChange changed_states,
GtkAccessiblePropertyChange changed_properties,
GtkAccessibleRelationChange changed_relations,
GtkAccessibleAttributeSet *states,
GtkAccessibleAttributeSet *properties,
GtkAccessibleAttributeSet *relations)
{
}
static void
gtk_at_context_class_init (GtkATContextClass *klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
gobject_class->set_property = gtk_at_context_set_property;
gobject_class->get_property = gtk_at_context_get_property;
gobject_class->finalize = gtk_at_context_finalize;
klass->state_change = gtk_at_context_real_state_change;
/**
* GtkATContext:accessible-role:
*
* The accessible role used by the AT context.
*
* Depending on the given role, different states and properties can be
* set or retrieved.
*/
obj_props[PROP_ACCESSIBLE_ROLE] =
g_param_spec_enum ("accessible-role",
"Accessible Role",
"The accessible role of the AT context",
GTK_TYPE_ACCESSIBLE_ROLE,
GTK_ACCESSIBLE_ROLE_NONE,
G_PARAM_READWRITE |
G_PARAM_CONSTRUCT_ONLY |
G_PARAM_STATIC_STRINGS);
/**
* GtkATContext:accessible:
*
* The #GtkAccessible that created the #GtkATContext instance.
*/
obj_props[PROP_ACCESSIBLE] =
g_param_spec_object ("accessible",
"Accessible",
"The accessible implementation",
GTK_TYPE_ACCESSIBLE,
G_PARAM_READWRITE |
G_PARAM_CONSTRUCT_ONLY |
G_PARAM_STATIC_STRINGS);
/**
* GtkATContext::state-change:
* @self: the #GtkATContext
* @changed_states: flags for the changed states
* @changed_properties: flags for the changed properties
* @changed_relations:
* @states: the new states
* @properties: the new properties
* @relations: the new relations
*
* Emitted when the attributes of the accessible for the
* #GtkATContext instance change.
*/
obj_signals[STATE_CHANGE] =
g_signal_new ("state-change",
G_TYPE_FROM_CLASS (gobject_class),
G_SIGNAL_RUN_FIRST,
G_STRUCT_OFFSET (GtkATContextClass, state_change),
NULL, NULL,
NULL,
G_TYPE_NONE, 6,
G_TYPE_UINT, G_TYPE_UINT, G_TYPE_UINT,
G_TYPE_POINTER, G_TYPE_POINTER, G_TYPE_POINTER);
g_object_class_install_properties (gobject_class, N_PROPS, obj_props);
}
#define N_PROPERTIES (GTK_ACCESSIBLE_PROPERTY_VALUE_TEXT + 1)
#define N_RELATIONS (GTK_ACCESSIBLE_RELATION_SET_SIZE + 1)
#define N_STATES (GTK_ACCESSIBLE_STATE_SELECTED + 1)
static const char *property_attrs[] = {
[GTK_ACCESSIBLE_PROPERTY_AUTOCOMPLETE] = "autocomplete",
[GTK_ACCESSIBLE_PROPERTY_DESCRIPTION] = "description",
[GTK_ACCESSIBLE_PROPERTY_HAS_POPUP] = "haspopup",
[GTK_ACCESSIBLE_PROPERTY_KEY_SHORTCUTS] = "keyshortcuts",
[GTK_ACCESSIBLE_PROPERTY_LABEL] = "label",
[GTK_ACCESSIBLE_PROPERTY_LEVEL] = "level",
[GTK_ACCESSIBLE_PROPERTY_MODAL] = "modal",
[GTK_ACCESSIBLE_PROPERTY_MULTI_LINE] = "multiline",
[GTK_ACCESSIBLE_PROPERTY_MULTI_SELECTABLE] = "multiselectable",
[GTK_ACCESSIBLE_PROPERTY_ORIENTATION] = "orientation",
[GTK_ACCESSIBLE_PROPERTY_PLACEHOLDER] = "placeholder",
[GTK_ACCESSIBLE_PROPERTY_READ_ONLY] = "readonly",
[GTK_ACCESSIBLE_PROPERTY_REQUIRED] = "required",
[GTK_ACCESSIBLE_PROPERTY_ROLE_DESCRIPTION] = "roledescription",
[GTK_ACCESSIBLE_PROPERTY_SORT] = "sort",
[GTK_ACCESSIBLE_PROPERTY_VALUE_MAX] = "valuemax",
[GTK_ACCESSIBLE_PROPERTY_VALUE_MIN] = "valuemin",
[GTK_ACCESSIBLE_PROPERTY_VALUE_NOW] = "valuenow",
[GTK_ACCESSIBLE_PROPERTY_VALUE_TEXT] = "valuetext",
};
/*< private >
* gtk_accessible_property_get_attribute_name:
* @property: a #GtkAccessibleProperty
*
* Retrieves the name of a #GtkAccessibleProperty.
*
* Returns: (transfer none): the name of the accessible property
*/
const char *
gtk_accessible_property_get_attribute_name (GtkAccessibleProperty property)
{
g_return_val_if_fail (property >= GTK_ACCESSIBLE_PROPERTY_AUTOCOMPLETE &&
property <= GTK_ACCESSIBLE_PROPERTY_VALUE_TEXT,
"<none>");
return property_attrs[property];
}
static const char *relation_attrs[] = {
[GTK_ACCESSIBLE_RELATION_ACTIVE_DESCENDANT] = "activedescendant",
[GTK_ACCESSIBLE_RELATION_COL_COUNT] = "colcount",
[GTK_ACCESSIBLE_RELATION_COL_INDEX] = "colindex",
[GTK_ACCESSIBLE_RELATION_COL_INDEX_TEXT] = "colindextext",
[GTK_ACCESSIBLE_RELATION_COL_SPAN] = "colspan",
[GTK_ACCESSIBLE_RELATION_CONTROLS] = "controls",
[GTK_ACCESSIBLE_RELATION_DESCRIBED_BY] = "describedby",
[GTK_ACCESSIBLE_RELATION_DETAILS] = "details",
[GTK_ACCESSIBLE_RELATION_ERROR_MESSAGE] = "errormessage",
[GTK_ACCESSIBLE_RELATION_FLOW_TO] = "flowto",
[GTK_ACCESSIBLE_RELATION_LABELLED_BY] = "labelledby",
[GTK_ACCESSIBLE_RELATION_OWNS] = "owns",
[GTK_ACCESSIBLE_RELATION_POS_IN_SET] = "posinset",
[GTK_ACCESSIBLE_RELATION_ROW_COUNT] = "rowcount",
[GTK_ACCESSIBLE_RELATION_ROW_INDEX] = "rowindex",
[GTK_ACCESSIBLE_RELATION_ROW_INDEX_TEXT] = "rowindextext",
[GTK_ACCESSIBLE_RELATION_ROW_SPAN] = "rowspan",
[GTK_ACCESSIBLE_RELATION_SET_SIZE] = "setsize",
};
/*< private >
* gtk_accessible_relation_get_attribute_name:
* @relation: a #GtkAccessibleRelation
*
* Retrieves the name of a #GtkAccessibleRelation.
*
* Returns: (transfer none): the name of the accessible relation
*/
const char *
gtk_accessible_relation_get_attribute_name (GtkAccessibleRelation relation)
{
g_return_val_if_fail (relation >= GTK_ACCESSIBLE_RELATION_ACTIVE_DESCENDANT &&
relation <= GTK_ACCESSIBLE_RELATION_SET_SIZE,
"<none>");
return relation_attrs[relation];
}
static const char *state_attrs[] = {
[GTK_ACCESSIBLE_STATE_BUSY] = "busy",
[GTK_ACCESSIBLE_STATE_CHECKED] = "checked",
[GTK_ACCESSIBLE_STATE_DISABLED] = "disabled",
[GTK_ACCESSIBLE_STATE_EXPANDED] = "expanded",
[GTK_ACCESSIBLE_STATE_HIDDEN] = "hidden",
[GTK_ACCESSIBLE_STATE_INVALID] = "invalid",
[GTK_ACCESSIBLE_STATE_PRESSED] = "pressed",
[GTK_ACCESSIBLE_STATE_SELECTED] = "selected",
};
/*< private >
* gtk_accessible_state_get_attribute_name:
* @state: a #GtkAccessibleState
*
* Retrieves the name of a #GtkAccessibleState.
*
* Returns: (transfer none): the name of the accessible state
*/
const char *
gtk_accessible_state_get_attribute_name (GtkAccessibleState state)
{
g_return_val_if_fail (state >= GTK_ACCESSIBLE_STATE_BUSY &&
state <= GTK_ACCESSIBLE_STATE_SELECTED,
"<none>");
return state_attrs[state];
}
static void
gtk_at_context_init (GtkATContext *self)
{
self->accessible_role = GTK_ACCESSIBLE_ROLE_NONE;
self->properties =
gtk_accessible_attribute_set_new (N_PROPERTIES,
property_attrs,
(GtkAccessibleAttributeDefaultFunc) gtk_accessible_value_get_default_for_property);
self->relations =
gtk_accessible_attribute_set_new (N_RELATIONS,
relation_attrs,
(GtkAccessibleAttributeDefaultFunc) gtk_accessible_value_get_default_for_relation);
self->states =
gtk_accessible_attribute_set_new (N_STATES,
state_attrs,
(GtkAccessibleAttributeDefaultFunc) gtk_accessible_value_get_default_for_state);
}
/**
* gtk_at_context_get_accessible:
* @self: a #GtkATContext
*
* Retrieves the #GtkAccessible using this context.
*
* Returns: (transfer none): a #GtkAccessible
*/
GtkAccessible *
gtk_at_context_get_accessible (GtkATContext *self)
{
g_return_val_if_fail (GTK_IS_AT_CONTEXT (self), NULL);
return self->accessible;
}
/**
* gtk_at_context_get_accessible_role:
* @self: a #GtkATContext
*
* Retrieves the accessible role of this context.
*
* Returns: a #GtkAccessibleRole
*/
GtkAccessibleRole
gtk_at_context_get_accessible_role (GtkATContext *self)
{
g_return_val_if_fail (GTK_IS_AT_CONTEXT (self), GTK_ACCESSIBLE_ROLE_NONE);
return self->accessible_role;
}
/**
* gtk_at_context_create: (constructor)
* @accessible_role: the accessible role used by the #GtkATContext
* @accessible: the #GtkAccessible implementation using the #GtkATContext
*
* Creates a new #GtkATContext instance for the given accessible role and
* accessible instance.
*
* The #GtkATContext implementation being instantiated will depend on the
* platform.
*
* Returns: (nullable) (transfer full): the #GtkATContext
*/
GtkATContext *
gtk_at_context_create (GtkAccessibleRole accessible_role,
GtkAccessible *accessible)
{
static const char *gtk_test_accessible;
static const char *gtk_no_a11y;
if (G_UNLIKELY (gtk_test_accessible == NULL))
{
const char *env = g_getenv ("GTK_TEST_ACCESSIBLE");
if (env != NULL && *env !='\0')
gtk_test_accessible = "1";
else
gtk_test_accessible = "0";
}
if (G_UNLIKELY (gtk_no_a11y == NULL))
{
const char *env = g_getenv ("GTK_NO_A11Y");
if (env != NULL && *env != '\0')
gtk_no_a11y = "1";
else
gtk_no_a11y = "0";
}
/* Shortcut everything if we're running with the test AT context */
if (gtk_test_accessible[0] == '1')
return gtk_test_at_context_new (accessible_role, accessible);
if (gtk_no_a11y[0] == '1')
return NULL;
/* FIXME: Add GIOExtension for AT contexts */
return gtk_test_at_context_new (accessible_role, accessible);
}
/*< private >
* gtk_at_context_update:
* @self: a #GtkATContext
*
* Notifies the AT connected to this #GtkATContext that the accessible
* state and its properties have changed.
*/
void
gtk_at_context_update (GtkATContext *self)
{
g_return_if_fail (GTK_IS_AT_CONTEXT (self));
GtkAccessibleStateChange changed_states =
gtk_accessible_attribute_set_get_changed (self->states);
GtkAccessiblePropertyChange changed_properties =
gtk_accessible_attribute_set_get_changed (self->properties);
GtkAccessibleRelationChange changed_relations =
gtk_accessible_attribute_set_get_changed (self->relations);
g_signal_emit (self, obj_signals[STATE_CHANGE], 0,
changed_states, changed_properties, changed_relations,
self->states, self->properties, self->relations);
}
/*< private >
* gtk_at_context_set_accessible_state:
* @self: a #GtkATContext
* @state: a #GtkAccessibleState
* @value: (nullable): #GtkAccessibleValue
*
* Sets the @value for the given @state of a #GtkATContext.
*
* If @value is %NULL, the state is unset.
*
* This function will accumulate state changes until gtk_at_context_update_state()
* is called.
*/
void
gtk_at_context_set_accessible_state (GtkATContext *self,
GtkAccessibleState state,
GtkAccessibleValue *value)
{
g_return_if_fail (GTK_IS_AT_CONTEXT (self));
if (value != NULL)
gtk_accessible_attribute_set_add (self->states, state, value);
else
gtk_accessible_attribute_set_remove (self->states, state);
}
/*< private >
* gtk_at_context_has_accessible_state:
* @self: a #GtkATContext
* @state: a #GtkAccessibleState
*
* Checks whether a #GtkATContext has the given @state set.
*
* Returns: %TRUE, if the accessible state is set
*/
gboolean
gtk_at_context_has_accessible_state (GtkATContext *self,
GtkAccessibleState state)
{
g_return_val_if_fail (GTK_IS_AT_CONTEXT (self), FALSE);
return gtk_accessible_attribute_set_contains (self->states, state);
}
/*< private >
* gtk_at_context_get_accessible_state:
* @self: a #GtkATContext
* @state: a #GtkAccessibleState
*
* Retrieves the value for the accessible state of a #GtkATContext.
*
* Returns: (transfer none): the value for the given state
*/
GtkAccessibleValue *
gtk_at_context_get_accessible_state (GtkATContext *self,
GtkAccessibleState state)
{
g_return_val_if_fail (GTK_IS_AT_CONTEXT (self), NULL);
return gtk_accessible_attribute_set_get_value (self->states, state);
}
/*< private >
* gtk_at_context_set_accessible_property:
* @self: a #GtkATContext
* @property: a #GtkAccessibleProperty
* @value: (nullable): #GtkAccessibleValue
*
* Sets the @value for the given @property of a #GtkATContext.
*
* If @value is %NULL, the property is unset.
*
* This function will accumulate property changes until gtk_at_context_update_state()
* is called.
*/
void
gtk_at_context_set_accessible_property (GtkATContext *self,
GtkAccessibleProperty property,
GtkAccessibleValue *value)
{
g_return_if_fail (GTK_IS_AT_CONTEXT (self));
if (value != NULL)
gtk_accessible_attribute_set_add (self->properties, property, value);
else
gtk_accessible_attribute_set_remove (self->properties, property);
}
/*< private >
* gtk_at_context_has_accessible_property:
* @self: a #GtkATContext
* @property: a #GtkAccessibleProperty
*
* Checks whether a #GtkATContext has the given @property set.
*
* Returns: %TRUE, if the accessible property is set
*/
gboolean
gtk_at_context_has_accessible_property (GtkATContext *self,
GtkAccessibleProperty property)
{
g_return_val_if_fail (GTK_IS_AT_CONTEXT (self), FALSE);
return gtk_accessible_attribute_set_contains (self->properties, property);
}
/*< private >
* gtk_at_context_get_accessible_property:
* @self: a #GtkATContext
* @property: a #GtkAccessibleProperty
*
* Retrieves the value for the accessible property of a #GtkATContext.
*
* Returns: (transfer none): the value for the given property
*/
GtkAccessibleValue *
gtk_at_context_get_accessible_property (GtkATContext *self,
GtkAccessibleProperty property)
{
g_return_val_if_fail (GTK_IS_AT_CONTEXT (self), NULL);
return gtk_accessible_attribute_set_get_value (self->properties, property);
}
/*< private >
* gtk_at_context_set_accessible_relation:
* @self: a #GtkATContext
* @relation: a #GtkAccessibleRelation
* @value: (nullable): #GtkAccessibleValue
*
* Sets the @value for the given @relation of a #GtkATContext.
*
* If @value is %NULL, the relation is unset.
*
* This function will accumulate relation changes until gtk_at_context_update_state()
* is called.
*/
void
gtk_at_context_set_accessible_relation (GtkATContext *self,
GtkAccessibleRelation relation,
GtkAccessibleValue *value)
{
g_return_if_fail (GTK_IS_AT_CONTEXT (self));
if (value != NULL)
gtk_accessible_attribute_set_add (self->relations, relation, value);
else
gtk_accessible_attribute_set_remove (self->relations, relation);
}
/*< private >
* gtk_at_context_has_accessible_relation:
* @self: a #GtkATContext
* @relation: a #GtkAccessibleRelation
*
* Checks whether a #GtkATContext has the given @relation set.
*
* Returns: %TRUE, if the accessible relation is set
*/
gboolean
gtk_at_context_has_accessible_relation (GtkATContext *self,
GtkAccessibleRelation relation)
{
g_return_val_if_fail (GTK_IS_AT_CONTEXT (self), FALSE);
return gtk_accessible_attribute_set_contains (self->relations, relation);
}
/*< private >
* gtk_at_context_get_accessible_relation:
* @self: a #GtkATContext
* @relation: a #GtkAccessibleRelation
*
* Retrieves the value for the accessible relation of a #GtkATContext.
*
* Returns: (transfer none): the value for the given relation
*/
GtkAccessibleValue *
gtk_at_context_get_accessible_relation (GtkATContext *self,
GtkAccessibleRelation relation)
{
g_return_val_if_fail (GTK_IS_AT_CONTEXT (self), NULL);
return gtk_accessible_attribute_set_get_value (self->relations, relation);
}