Base class for accessible Components. More...

#include <juce_AccessibilityHandler.h>

Collaboration diagram for juce::AccessibilityHandler:

[legend]

Classes
struct	Interfaces
	Utility struct which holds one or more accessibility interfaces. More...

Public Types
enum	AnnouncementPriority { AnnouncementPriority::low, AnnouncementPriority::medium, AnnouncementPriority::high }
	A priority level that can help an accessibility client determine how to handle an announcement request. More...

Public Member Functions
	AccessibilityHandler (Component &componentToWrap, AccessibilityRole accessibilityRole, AccessibilityActions actions={}, Interfaces interfaces={})
	Constructor. More...

virtual	~AccessibilityHandler ()
	Destructor. More...

const AccessibilityActions &	getActions () const noexcept
	Returns the set of actions that the UI element supports and the associated callbacks. More...

AccessibilityCellInterface *	getCellInterface () const
	Returns the cell interface for this UI element, or nullptr if it is not supported. More...

AccessibilityHandler *	getChildAt (Point< int > screenPoint)
	Returns the deepest child of this UI element in the accessibility hierarchy that contains the given screen point, or nullptr if there is no child at this point. More...

AccessibilityHandler *	getChildFocus ()
	Returns the deepest UI element which currently has focus. More...

std::vector< AccessibilityHandler * >	getChildren () const
	Returns the unignored children of this UI element in the accessibility hierarchy. More...

const Component &	getComponent () const noexcept
	Returns the Component that this handler represents. More...

Component &	getComponent () noexcept
	Returns the Component that this handler represents. More...

virtual AccessibleState	getCurrentState () const
	Returns the current state of the UI element. More...

virtual String	getDescription () const
	A short description of the UI element. More...

virtual String	getHelp () const
	Some help text for the UI element (if required). More...

AccessibilityNativeHandle *	getNativeImplementation () const

AccessibilityHandler *	getParent () const
	Returns the first unignored parent of this UI element in the accessibility hierarchy, or nullptr if this is a root element without a parent. More...

AccessibilityRole	getRole () const noexcept
	The type of UI element that this accessibility handler represents. More...

AccessibilityTableInterface *	getTableInterface () const
	Returns the table interface for this UI element, or nullptr if it is not supported. More...

AccessibilityTextInterface *	getTextInterface () const
	Returns the text interface for this UI element, or nullptr if it is not supported. More...

virtual String	getTitle () const
	The title of the UI element. More...

std::type_index	getTypeIndex () const

AccessibilityValueInterface *	getValueInterface () const
	Returns the value interface for this UI element, or nullptr if it is not supported. More...

void	giveAwayFocus () const
	If this UI element or any of its children in the accessibility hierarchy currently have focus, this will defocus it. More...

void	grabFocus ()
	Tries to give focus to this UI element. More...

bool	hasFocus (bool trueIfChildFocused) const
	Returns true if this UI element has the focus. More...

bool	isIgnored () const
	Returns true if this UI element should be ignored by accessibility clients. More...

bool	isParentOf (const AccessibilityHandler *possibleChild) const noexcept
	Checks whether a given UI element is a child of this one in the accessibility hierarchy. More...

bool	isVisibleWithinParent () const
	Returns true if this UI element is visible within its parent. More...

void	notifyAccessibilityEvent (AccessibilityEvent event) const
	Used to send a notification to any observing accessibility clients that something has changed in the UI element. More...

Static Public Member Functions
static void	postAnnouncement (const String &announcementString, AnnouncementPriority priority)
	Posts an announcement to be made to the user. More...

Private Member Functions
void	giveAwayFocusInternal () const

void	grabFocusInternal (bool)

void	takeFocus ()

Static Private Member Functions
static std::unique_ptr< AccessibilityNativeImpl >	createNativeImpl (AccessibilityHandler &)

Private Attributes
AccessibilityActions	actions

Component &	component

Interfaces	interfaces

std::unique_ptr< AccessibilityNativeImpl >	nativeImpl

const AccessibilityRole	role

std::type_index	typeIndex

Static Private Attributes
static AccessibilityHandler *	currentlyFocusedHandler

Friends
class	AccessibilityNativeHandle

Detailed Description

Base class for accessible Components.

This class wraps a Component and provides methods that allow an accessibility client, such as VoiceOver on macOS, or Narrator on Windows, to control it.

It handles hierarchical navigation, properties, state, and various interfaces.

@tags{Accessibility}

Member Enumeration Documentation

◆ AnnouncementPriority

enum juce::AccessibilityHandler::AnnouncementPriority

strong

A priority level that can help an accessibility client determine how to handle an announcement request.

Exactly what this controls is platform-specific, but generally a low priority announcement will be read when the screen reader is free, whereas a high priority announcement will interrupt the current speech.

Enumerator
low
medium
high

Constructor & Destructor Documentation

◆ AccessibilityHandler()

juce::AccessibilityHandler::AccessibilityHandler	(	Component &	componentToWrap,
		AccessibilityRole	accessibilityRole,
		AccessibilityActions	actions = `{}`,
		Interfaces	interfaces = `{}`
	)

Constructor.

This will create a AccessibilityHandler which wraps the provided Component and makes it visible to accessibility clients. You must also specify a role for the UI element from the AccessibilityRole list which best describes it.

To enable users to interact with the UI element you should provide the set of supported actions and their associated callbacks via the accessibilityActions parameter.

For UI elements that support more complex interaction the value, text, table, and cell interfaces should be implemented as required and passed as the final argument of this constructor. See the documentation of these classes for more information about the types of control they represent and which methods need to be implemented.

◆ ~AccessibilityHandler()

virtual juce::AccessibilityHandler::~AccessibilityHandler ( )

virtual

Destructor.

Member Function Documentation

◆ createNativeImpl()

static std::unique_ptr<AccessibilityNativeImpl> juce::AccessibilityHandler::createNativeImpl ( AccessibilityHandler & )

staticprivate

◆ getActions()

const AccessibilityActions& juce::AccessibilityHandler::getActions ( ) const

noexcept

Returns the set of actions that the UI element supports and the associated callbacks.

◆ getCellInterface()

AccessibilityCellInterface* juce::AccessibilityHandler::getCellInterface ( ) const

Returns the cell interface for this UI element, or nullptr if it is not supported.

See also: AccessibilityCellInterface

◆ getChildAt()

AccessibilityHandler* juce::AccessibilityHandler::getChildAt ( Point< int > screenPoint )

Returns the deepest child of this UI element in the accessibility hierarchy that contains the given screen point, or nullptr if there is no child at this point.

◆ getChildFocus()

AccessibilityHandler* juce::AccessibilityHandler::getChildFocus ( )

Returns the deepest UI element which currently has focus.

This can be a child of this UI element or, if no child is focused, this element itself.

Note that this can be different to the value of the Component with keyboard focus returned by Component::getCurrentlyFocusedComponent().

See also: hasFocus

◆ getChildren()

std::vector<AccessibilityHandler*> juce::AccessibilityHandler::getChildren ( ) const

Returns the unignored children of this UI element in the accessibility hierarchy.

◆ getComponent() [1/2]

const Component& juce::AccessibilityHandler::getComponent ( ) const

inlinenoexcept

Returns the Component that this handler represents.

Referenced by juce::UIATransformProvider::getPeer(), juce::UIAWindowProvider::getPeer(), and juce::AccessibilityNativeHandle::isFragmentRoot().

◆ getComponent() [2/2]

Component& juce::AccessibilityHandler::getComponent ( )

inlinenoexcept

Returns the Component that this handler represents.

◆ getCurrentState()

virtual AccessibleState juce::AccessibilityHandler::getCurrentState ( ) const

virtual

Returns the current state of the UI element.

The default implementation of this method will set the focusable flag and, if this UI element is currently focused, will also set the focused flag.

Referenced by juce::UIAExpandCollapseProvider::get_ExpandCollapseState(), juce::UIAToggleProvider::getCurrentToggleState(), and juce::UIASelectionProvider::isMultiSelectable().

◆ getDescription()

virtual String juce::AccessibilityHandler::getDescription ( ) const

inlinevirtual

A short description of the UI element.

This may be read out by the system. It should not include the type of the UI element and should ideally be a single word, for example "Open" for a button that opens a window.

The default implementation will call Component::getDescription(), but you can override this to return a different string if required.

If neither a name nor a description is provided then the UI element may be ignored by accessibility clients.

This must be a localised string.

◆ getHelp()

virtual String juce::AccessibilityHandler::getHelp ( ) const

inlinevirtual

Some help text for the UI element (if required).

This may be read out by the system. This string functions in a similar way to a tooltip, for example "Click to open window." for a button which opens a window.

The default implementation will call Component::getHelpText(), but you can override this to return a different string if required.

This must be a localised string.

◆ getNativeImplementation()

AccessibilityNativeHandle* juce::AccessibilityHandler::getNativeImplementation ( ) const

Referenced by juce::UIATextProvider::UIATextRangeProvider::GetEnclosingElement().

◆ getParent()

AccessibilityHandler* juce::AccessibilityHandler::getParent ( ) const

Returns the first unignored parent of this UI element in the accessibility hierarchy, or nullptr if this is a root element without a parent.

◆ getRole()

AccessibilityRole juce::AccessibilityHandler::getRole ( ) const

inlinenoexcept

The type of UI element that this accessibility handler represents.

See also: AccessibilityRole

◆ getTableInterface()

AccessibilityTableInterface* juce::AccessibilityHandler::getTableInterface ( ) const

Returns the table interface for this UI element, or nullptr if it is not supported.

See also: AccessibilityTableInterface

◆ getTextInterface()

AccessibilityTextInterface* juce::AccessibilityHandler::getTextInterface ( ) const

Returns the text interface for this UI element, or nullptr if it is not supported.

See also: AccessibilityTextInterface

◆ getTitle()

virtual String juce::AccessibilityHandler::getTitle ( ) const

inlinevirtual

The title of the UI element.

This will be read out by the system and should be concise, preferably matching the visible title of the UI element (if any). For example, this might be the text of a button or a simple label.

The default implementation will call Component::getTitle(), but you can override this to return a different string if required.

If neither a name nor a description is provided then the UI element may be ignored by accessibility clients.

This must be a localised string.

◆ getTypeIndex()

std::type_index juce::AccessibilityHandler::getTypeIndex ( ) const

inline

◆ getValueInterface()

AccessibilityValueInterface* juce::AccessibilityHandler::getValueInterface ( ) const

Returns the value interface for this UI element, or nullptr if it is not supported.

See also: AccessibilityValueInterface

Referenced by juce::UIAValueProvider::get_IsReadOnly(), and juce::UIAValueProvider::get_Value().

◆ giveAwayFocus()

void juce::AccessibilityHandler::giveAwayFocus ( ) const

If this UI element or any of its children in the accessibility hierarchy currently have focus, this will defocus it.

This will also give away the keyboard focus from the Component it represents, and notify any listening accessibility clients that the current focus has changed.

See also: hasFocus, grabFocus

◆ giveAwayFocusInternal()

void juce::AccessibilityHandler::giveAwayFocusInternal ( ) const

private

◆ grabFocus()

void juce::AccessibilityHandler::grabFocus ( )

Tries to give focus to this UI element.

If the UI element is focusable and not ignored this will update the currently focused element, try to give keyboard focus to the Component it represents, and notify any listening accessibility clients that the current focus has changed.

See also: hasFocus, giveAwayFocus

◆ grabFocusInternal()

void juce::AccessibilityHandler::grabFocusInternal ( bool )

private

◆ hasFocus()

bool juce::AccessibilityHandler::hasFocus ( bool trueIfChildFocused ) const

Returns true if this UI element has the focus.

Parameters

trueIfChildFocused if this is true, this method will also return true if any child of this UI element in the accessibility hierarchy has focus

Referenced by juce::UIATextProvider::GetCaretRange().

◆ isIgnored()

bool juce::AccessibilityHandler::isIgnored ( ) const

Returns true if this UI element should be ignored by accessibility clients.

◆ isParentOf()

bool juce::AccessibilityHandler::isParentOf ( const AccessibilityHandler * possibleChild ) const

noexcept

Checks whether a given UI element is a child of this one in the accessibility hierarchy.

◆ isVisibleWithinParent()

bool juce::AccessibilityHandler::isVisibleWithinParent ( ) const

Returns true if this UI element is visible within its parent.

This will always return true for UI elements with the AccessibleState::accessibleOffscreen flag set.

◆ notifyAccessibilityEvent()

void juce::AccessibilityHandler::notifyAccessibilityEvent ( AccessibilityEvent event ) const

Used to send a notification to any observing accessibility clients that something has changed in the UI element.

See also: AccessibilityEvent

◆ postAnnouncement()

static void juce::AccessibilityHandler::postAnnouncement	(	const String &	announcementString,
		AnnouncementPriority	priority
	)

static

Posts an announcement to be made to the user.

Parameters

announcementString	a localised string containing the announcement to be read out
priority	the appropriate priority level for the announcement

◆ takeFocus()

void juce::AccessibilityHandler::takeFocus ( )

private

Friends And Related Function Documentation

◆ AccessibilityNativeHandle

friend class AccessibilityNativeHandle

friend

Member Data Documentation

◆ actions

AccessibilityActions juce::AccessibilityHandler::actions

private

◆ component

Component& juce::AccessibilityHandler::component

private

◆ currentlyFocusedHandler

AccessibilityHandler* juce::AccessibilityHandler::currentlyFocusedHandler

staticprivate

◆ interfaces

Interfaces juce::AccessibilityHandler::interfaces

private

◆ nativeImpl

std::unique_ptr<AccessibilityNativeImpl> juce::AccessibilityHandler::nativeImpl

private

◆ role

const AccessibilityRole juce::AccessibilityHandler::role

private

◆ typeIndex

std::type_index juce::AccessibilityHandler::typeIndex

private

The documentation for this class was generated from the following file:

juce_AccessibilityHandler.h

Classes

Public Types

Public Member Functions

Static Public Member Functions

Private Member Functions

Static Private Member Functions

Private Attributes

Static Private Attributes

Friends

Detailed Description

Member Enumeration Documentation

◆ AnnouncementPriority

Constructor & Destructor Documentation

◆ AccessibilityHandler()

◆ ~AccessibilityHandler()

Member Function Documentation

◆ createNativeImpl()

◆ getActions()

◆ getCellInterface()

◆ getChildAt()

◆ getChildFocus()

◆ getChildren()

◆ getComponent() [1/2]

◆ getComponent() [2/2]

◆ getCurrentState()

◆ getDescription()

◆ getHelp()

◆ getNativeImplementation()

◆ getParent()

◆ getRole()

◆ getTableInterface()

◆ getTextInterface()

◆ getTitle()

◆ getTypeIndex()

◆ getValueInterface()

◆ giveAwayFocus()

◆ giveAwayFocusInternal()

◆ grabFocus()

◆ grabFocusInternal()

◆ hasFocus()

◆ isIgnored()

◆ isParentOf()

◆ isVisibleWithinParent()

◆ notifyAccessibilityEvent()

◆ postAnnouncement()

◆ takeFocus()

Friends And Related Function Documentation

◆ AccessibilityNativeHandle

Member Data Documentation

◆ actions

◆ component

◆ currentlyFocusedHandler

◆ interfaces

◆ nativeImpl

◆ role

◆ typeIndex