Namespace

Atk – 1.0

GNOME provides support for accessibility devices using the ATK framework. This framework defines a set of interfaces to which graphical interface components adhere. This allows, for instance, screen readers to read the text of an interface and interact with its controls. ATK support is built into GTK+ 3 and the rest of the GNOME platform, so any application using GTK+ 3 will have reasonable accessibility support for free. GTK4 now includes accessibility support natively and does not need ATK.

Version2.51.90
AuthorsATK Development Team
LicenseLGPL-2.1-or-later
Websitehttps://wiki.gnome.org/Accessibility
Sourcehttps://gitlab.gnome.org/GNOME/at-spi2-core/

Build

C headersatk/atk.h
pkg-config filesatk

Dependencies

GObject—2.0 The base type system library
Browse documentation
AT-SPI The Assistive Technology Service Provider Interface
Browse documentation

Additional documentation

Classes

GObjectAccessible

This object class is derived from AtkObject and can be used as a basis implementing accessible objects.

Hyperlink

An ATK object which encapsulates a link or set of links in a hypertext document.

Misc

A set of ATK utility functions for thread locking.

NoOpObject

An AtkObject which purports to implement all ATK interfaces.

NoOpObjectFactory

The AtkObjectFactory which creates an AtkNoOpObject.

Object

The base object class for the Accessibility Toolkit API.

ObjectFactory

The base object class for a factory used to create accessible objects for objects of a specific GType.

Plug

Toplevel for embedding into other processes.

Registry

An object used to store the GType of the factories used to create an accessible object for an object of a particular GType.

Relation

An object used to describe a relation between a object and one or more other objects.

RelationSet

A set of AtkRelations, normally the set of AtkRelations which an AtkObject has.

Socket

Container for AtkPlug objects from other processes.

StateSet

An AtkStateSet contains the states of an object.

Util

A set of ATK utility functions for event and toolkit support.

Interfaces

Action

The ATK interface provided by UI components which the user can activate/interact with.

Component

The ATK interface provided by UI components which occupy a physical area on the screen. which the user can activate/interact with.

Document

The ATK interface which represents the toplevel container for document content.

EditableText

The ATK interface implemented by components containing user-editable text content.

HyperlinkImpl

A queryable interface which allows AtkHyperlink instances associated with an AtkObject to be obtained. AtkHyperlinkImpl corresponds to AT-SPI’s Hyperlink interface, and differs from AtkHyperlink in that AtkHyperlink is an object type, rather than an interface, and thus cannot be directly queried. FTW.

Hypertext

The ATK interface which provides standard mechanism for manipulating hyperlinks.

Image

The ATK Interface implemented by components which expose image or pixmap content on-screen.

ImplementorIface

The AtkImplementor interface is implemented by objects for which AtkObject peers may be obtained via calls to iface->(ref_accessible)(implementor);

Selection

The ATK interface implemented by container objects whose AtkObject children can be selected.

StreamableContent

The ATK interface which provides access to streamable content.

Table

The ATK interface implemented for UI components which contain tabular or row/column information.

TableCell

The ATK interface implemented for a cell inside a two-dimentional AtkTable.

Text

The ATK interface implemented by components with text content.

Value

The ATK interface implemented by valuators and components which display or select a value from a bounded range of values.

Window

The ATK Interface provided by UI components that represent a top-level window.

Structs

Attribute

AtkAttribute is a string name/value pair representing a generic attribute. This can be used to expose additional information from an accessible object as a whole (see atk_object_get_attributes()) or an document (see atk_document_get_attributes()). In the case of text attributes (see atk_text_get_default_attributes()), AtkTextAttribute enum defines all the possible text attribute names. You can use atk_text_attribute_get_name() to get the string name from the enum value. See also atk_text_attribute_for_name() and atk_text_attribute_get_value() for more information.

Implementor

KeyEventStruct

Encapsulates information about a key event.

PropertyValues

valid value. This is a field defined with the purpose of contain the previous value of the property, but is not used anymore.

Range

A given range or subrange, to be used with AtkValue.

Rectangle

A data structure for holding a rectangle. Those coordinates are relative to the component top-level parent.

TextRange

A structure used to describe a text range.

TextRectangle

A structure used to store a rectangle used by AtkText.

TextSelection

This structure represents a single text selection within a document. This selection is defined by two points in the content, where each one is defined by an AtkObject supporting the AtkText interface and a character offset relative to it.

unstable since: 2.52

Aliases

AttributeSet

This is a singly-linked list (a GSList) of AtkAttribute. It is used by atk_text_get_run_attributes(), atk_text_get_default_attributes(), atk_editable_text_set_run_attributes(), atk_document_get_attributes() and atk_object_get_attributes()

State

An AtkState describes a single state of an object.

Enumerations

CoordType

Specifies how xy coordinates are to be interpreted. Used by functions such as atk_component_get_position() and atk_text_get_character_extents()

KeyEventType

Specifies the type of a keyboard evemt.

Layer

Describes the layer of a component.

Live

Enumeration used to indicate a type of live region and how assertive it should be in terms of speaking notifications. Currently, this is only used for “notification” events, but it may be used for additional purposes in the future.

since: 2.50

RelationType

Describes the type of the relation.

Role

Describes the role of an object.

ScrollType

Specifies where an object should be placed on the screen when using scroll_to.

since: 2.30

StateType

The possible types of states of an object.

TextAttribute

Describes the text attributes supported.

TextBoundary

Text boundary types used for specifying boundaries for regions of text. This enumeration is deprecated since 2.9.4 and should not be used. Use AtkTextGranularity with #atk_text_get_string_at_offset instead.

TextClipType

Describes the type of clipping required.

TextGranularity

Text granularity types used for specifying the granularity of the region of text we are interested in.

ValueType

Default types for a given value. Those are defined in order to easily get localized strings to describe a given value or a given subrange, using atk_value_type_get_localized_name().

Bitfields

HyperlinkStateFlags

Describes the type of link.

Callbacks

EventListener

A function which is called when an object emits a matching event, as used in #atk_add_focus_tracker. Currently the only events for which object-specific handlers are supported are events of type “focus:”. Most clients of ATK will prefer to attach signal handlers for the various ATK signals instead.

EventListenerInit

An AtkEventListenerInit function is a special function that is called in order to initialize the per-object event registration system used by AtkEventListener, if any preparation is required.

FocusHandler

The type of callback function used for atk_component_add_focus_handler() and atk_component_remove_focus_handler()

deprecated: 2.9.4 

Function

An AtkFunction is a function definition used for padding which has been added to class and interface structures to allow for expansion in the future.

KeySnoopFunc

An AtkKeySnoopFunc is a type of callback which is called whenever a key event occurs, if registered via atk_add_key_event_listener. It allows for pre-emptive interception of key events via the return code as described below.

PropertyChangeHandler

An AtkPropertyChangeHandler is a function which is executed when an AtkObject’s property changes value. It is specified in a call to atk_object_connect_property_change_handler().

deprecated: Unknown 

Functions

add_focus_tracker

Adds the specified function to the list of functions to be called when an object receives focus.

deprecated: 2.9.4 

add_global_event_listener

Adds the specified function to the list of functions to be called when an ATK event of type event_type occurs.

add_key_event_listener

Adds the specified function to the list of functions to be called when a key event occurs. The data element will be passed to the AtkKeySnoopFunc (listener) as the func_data param, on notification.

focus_tracker_init

Specifies the function to be called for focus tracker initialization. This function should be called by an implementation of the ATK interface if any specific work needs to be done to enable focus tracking.

deprecated: 2.9.4 

focus_tracker_notify

Cause the focus tracker functions which have been specified to be executed for the object.

deprecated: 2.9.4 

get_binary_age

Returns the binary age as passed to libtool when building the ATK library the process is running against.

since: 2.8

get_default_registry

Gets a default implementation of the AtkObjectFactory/type registry. Note: For most toolkit maintainers, this will be the correct registry for registering new AtkObject factories. Following a call to this function, maintainers may call atk_registry_set_factory_type() to associate an AtkObjectFactory subclass with the GType of objects for whom accessibility information will be provided.

get_focus_object

Gets the currently focused object.

since: 1.6

get_interface_age

Returns the interface age as passed to libtool when building the ATK library the process is running against.

since: 2.8

get_major_version

Returns the major version number of the ATK library. (e.g. in ATK version 2.7.4 this is 2.)

since: 2.8

get_micro_version

Returns the micro version number of the ATK library. (e.g. in ATK version 2.7.4 this is 4.)

since: 2.8

get_minor_version

Returns the minor version number of the ATK library. (e.g. in ATK version 2.7.4 this is 7.)

since: 2.8

get_root

Gets the root accessible container for the current application.

get_toolkit_name

Gets name string for the GUI toolkit implementing ATK for this application.

get_toolkit_version

Gets version string for the GUI toolkit implementing ATK for this application.

get_version

Gets the current version for ATK.

since: 1.20

remove_focus_tracker

Removes the specified focus tracker from the list of functions to be called when any object receives focus.

deprecated: 2.9.4 

remove_global_event_listener

listener_id is the value returned by #atk_add_global_event_listener when you registered that event listener.

remove_key_event_listener

listener_id is the value returned by #atk_add_key_event_listener when you registered that event listener.

Function Macros

CHECK_VERSION

Returns TRUE if the version of the ATK header files is the same as or newer than the passed-in version.

since: 2.7.4

DEFINE_ABSTRACT_TYPE

A convenience macro for ATK type implementations. Similar to ATK_DEFINE_TYPE(), but defines an abstract type.

since: 1.22

DEFINE_ABSTRACT_TYPE_WITH_CODE

A convenience macro for ATK type implementations. Similar to ATK_DEFINE_TYPE_WITH_CODE(), but defines an abstract type.

since: 1.22

DEFINE_TYPE

A convenience macro for type ATK implementations, which declares a class initialization function, an instance initialization function (see GTypeInfo for information about these) and a static variable named t_n _parent_class pointing to the parent class. Furthermore, it defines a _get_type() function.

since: 1.22

DEFINE_TYPE_EXTENDED

The most general convenience macro for ATK type implementations, on which ATK_DEFINE_TYPE(), etc are based.

since: 1.22

DEFINE_TYPE_WITH_CODE

A convenience macro for ATK type implementations. Similar to ATK_DEFINE_TYPE(), but allows you to insert custom code into the _get_type() function, e.g. interface implementations via G_IMPLEMENT_INTERFACE().

since: 1.22

DEPRECATED_FOR

DEPRECATED_IN_2_10_FOR

DEPRECATED_IN_2_12_FOR

DEPRECATED_IN_2_14_FOR

DEPRECATED_IN_2_2_FOR

DEPRECATED_IN_2_30_FOR

DEPRECATED_IN_2_36_FOR

DEPRECATED_IN_2_4_FOR

DEPRECATED_IN_2_6_FOR

DEPRECATED_IN_2_8_FOR

GOBJECT_ACCESSIBLE

GOBJECT_ACCESSIBLE_CLASS

NO_OP_OBJECT

NO_OP_OBJECT_CLASS

NO_OP_OBJECT_FACTORY

NO_OP_OBJECT_FACTORY_CLASS

UNAVAILABLE

Constants

BINARY_AGE

Like atk_get_binary_age(), but from the headers used at application compile time, rather than from the library linked against at application run time.

INTERFACE_AGE

Like atk_get_interface_age(), but from the headers used at application compile time, rather than from the library linked against at application run time.

MAJOR_VERSION

Like atk_get_major_version(), but from the headers used at application compile time, rather than from the library linked against at application run time.

MICRO_VERSION

Like atk_get_micro_version(), but from the headers used at application compile time, rather than from the library linked against at application run time.

MINOR_VERSION

Like atk_get_minor_version(), but from the headers used at application compile time, rather than from the library linked against at application run time.

VERSION_MIN_REQUIRED

A macro that should be defined by the user prior to including the atk/atk.h header. The definition should be one of the predefined ATK version macros: ATK_VERSION_2_12, ATK_VERSION_2_14,…