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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#ifndef __nsAccessibilityService_h__
#define __nsAccessibilityService_h__
#include "mozilla/a11y/CacheConstants.h"
#include "mozilla/a11y/DocManager.h"
#include "mozilla/a11y/FocusManager.h"
#include "mozilla/a11y/Platform.h"
#include "mozilla/a11y/Role.h"
#include "mozilla/a11y/SelectionManager.h"
#include "mozilla/Preferences.h"
#include "nsAtomHashKeys.h"
#include "nsIContent.h"
#include "nsIObserver.h"
#include "nsIAccessibleEvent.h"
#include "nsIEventListenerService.h"
#include "nsXULAppAPI.h"
#include "xpcAccessibilityService.h"
class nsImageFrame;
class nsIArray;
class nsITreeView;
namespace mozilla {
class PresShell;
class Monitor;
namespace dom {
class DOMStringList;
class Element;
} // namespace dom
namespace a11y {
class AccAttributes;
class Accessible;
class ApplicationAccessible;
class xpcAccessibleApplication;
/**
* Return focus manager.
*/
FocusManager* FocusMgr();
/**
* Return selection manager.
*/
SelectionManager* SelectionMgr();
/**
* Returns the application accessible.
*/
ApplicationAccessible* ApplicationAcc();
xpcAccessibleApplication* XPCApplicationAcc();
typedef LocalAccessible*(New_Accessible)(mozilla::dom::Element* aElement,
LocalAccessible* aContext);
// These fields are not `nsStaticAtom* const` because MSVC doesn't like it.
struct MarkupAttrInfo {
nsStaticAtom* name;
nsStaticAtom* value;
nsStaticAtom* DOMAttrName;
nsStaticAtom* DOMAttrValue;
};
struct MarkupMapInfo {
nsStaticAtom* const tag;
New_Accessible* new_func;
a11y::role role;
MarkupAttrInfo attrs[4];
};
struct XULMarkupMapInfo {
nsStaticAtom* const tag;
New_Accessible* new_func;
};
/**
* PREF_ACCESSIBILITY_FORCE_DISABLED preference change callback.
*/
void PrefChanged(const char* aPref, void* aClosure);
/**
* Read and normalize PREF_ACCESSIBILITY_FORCE_DISABLED preference.
*/
EPlatformDisabledState ReadPlatformDisabledState();
} // namespace a11y
} // namespace mozilla
class nsAccessibilityService final : public mozilla::a11y::DocManager,
public mozilla::a11y::FocusManager,
public mozilla::a11y::SelectionManager,
public nsIListenerChangeListener,
public nsIObserver {
public:
typedef mozilla::a11y::LocalAccessible LocalAccessible;
typedef mozilla::a11y::DocAccessible DocAccessible;
static const uint64_t kDefaultCacheDomains =
mozilla::a11y::CacheDomain::NameAndDescription |
mozilla::a11y::CacheDomain::State;
// nsIListenerChangeListener
NS_IMETHOD ListenersChanged(nsIArray* aEventChanges) override;
protected:
~nsAccessibilityService();
public:
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_NSIOBSERVER
LocalAccessible* GetRootDocumentAccessible(mozilla::PresShell* aPresShell,
bool aCanCreate);
/**
* Adds/remove ATK root accessible for gtk+ native window to/from children
* of the application accessible.
*/
LocalAccessible* AddNativeRootAccessible(void* aAtkAccessible);
void RemoveNativeRootAccessible(LocalAccessible* aRootAccessible);
bool HasAccessible(nsINode* aDOMNode);
/**
* Get a string equivalent for an accessible role value.
*/
void GetStringRole(uint32_t aRole, nsAString& aString);
/**
* Get a string equivalent for an accessible state/extra state.
*/
already_AddRefed<mozilla::dom::DOMStringList> GetStringStates(
uint64_t aStates) const;
void GetStringStates(uint32_t aState, uint32_t aExtraState,
nsISupports** aStringStates);
/**
* Get a string equivalent for an accessible event value.
*/
void GetStringEventType(uint32_t aEventType, nsAString& aString);
/**
* Get a string equivalent for an accessible event value.
*/
void GetStringEventType(uint32_t aEventType, nsACString& aString);
/**
* Get a string equivalent for an accessible relation type.
*/
void GetStringRelationType(uint32_t aRelationType, nsAString& aString);
// nsAccesibilityService
/**
* Notification used to update the accessible tree when new content is
* inserted.
*/
void ContentRangeInserted(mozilla::PresShell* aPresShell,
nsIContent* aStartChild, nsIContent* aEndChild);
/**
* Triggers a re-evaluation of the a11y tree of aContent after the next
* refresh. This is important because whether we create accessibles may
* depend on the frame tree / style.
*/
void ScheduleAccessibilitySubtreeUpdate(mozilla::PresShell* aPresShell,
nsIContent* aStartChild);
/**
* Notification used to update the accessible tree when content is removed.
*/
void ContentRemoved(mozilla::PresShell* aPresShell, nsIContent* aChild);
/**
* Notification used to invalidate the isLayoutTable cache.
*/
void TableLayoutGuessMaybeChanged(mozilla::PresShell* aPresShell,
nsIContent* aContent);
/**
* Notifies when a combobox <option> text or label changes.
*/
void ComboboxOptionMaybeChanged(mozilla::PresShell*,
nsIContent* aMutatingNode);
void UpdateText(mozilla::PresShell* aPresShell, nsIContent* aContent);
/**
* Update XUL:tree accessible tree when treeview is changed.
*/
void TreeViewChanged(mozilla::PresShell* aPresShell, nsIContent* aContent,
nsITreeView* aView);
/**
* Notify of input@type="element" value change.
*/
void RangeValueChanged(mozilla::PresShell* aPresShell, nsIContent* aContent);
/**
* Update the image map.
*/
void UpdateImageMap(nsImageFrame* aImageFrame);
/**
* Update the label accessible tree when rendered @value is changed.
*/
void UpdateLabelValue(mozilla::PresShell* aPresShell, nsIContent* aLabelElm,
const nsString& aNewValue);
/**
* Notify accessibility that anchor jump has been accomplished to the given
* target. Used by layout.
*/
void NotifyOfAnchorJumpTo(nsIContent* aTarget);
/**
* Notify that presshell is activated.
*/
void PresShellActivated(mozilla::PresShell* aPresShell);
/**
* Recreate an accessible for the given content node in the presshell.
*/
void RecreateAccessible(mozilla::PresShell* aPresShell, nsIContent* aContent);
void FireAccessibleEvent(uint32_t aEvent, LocalAccessible* aTarget);
void NotifyOfPossibleBoundsChange(mozilla::PresShell* aPresShell,
nsIContent* aContent);
void NotifyOfComputedStyleChange(mozilla::PresShell* aPresShell,
nsIContent* aContent);
void NotifyOfTabPanelVisibilityChange(mozilla::PresShell* aPresShell,
mozilla::dom::Element* aPanel,
bool aVisible);
void NotifyOfResolutionChange(mozilla::PresShell* aPresShell,
float aResolution);
void NotifyOfDevPixelRatioChange(mozilla::PresShell* aPresShell,
int32_t aAppUnitsPerDevPixel);
/**
* Notify accessibility that an element explicitly set for an attribute is
* about to change. See dom::Element::ExplicitlySetAttrElement.
*/
void NotifyAttrElementWillChange(mozilla::dom::Element* aElement,
nsAtom* aAttr);
/**
* Notify accessibility that an element explicitly set for an attribute has
* changed. See dom::Element::ExplicitlySetAttrElement.
*/
void NotifyAttrElementChanged(mozilla::dom::Element* aElement, nsAtom* aAttr);
// nsAccessibiltiyService
/**
* Return true if accessibility service has been shutdown.
*/
static bool IsShutdown() { return gConsumers == 0; };
/**
* Return true if there should be an image accessible for the given element.
*/
static bool ShouldCreateImgAccessible(mozilla::dom::Element* aElement,
DocAccessible* aDocument);
/*
* Set the currently-active cache domains.
*/
void SetCacheDomains(uint64_t aCacheDomains);
bool CacheDomainIsActive(uint64_t aCacheDomain) const {
return (gCacheDomains & aCacheDomain) != mozilla::a11y::CacheDomain::None;
}
/**
* Creates an accessible for the given DOM node.
*
* @param aNode [in] the given node
* @param aContext [in] context the accessible is created in
* @param aIsSubtreeHidden [out, optional] indicates whether the node's
* frame and its subtree is hidden
*/
LocalAccessible* CreateAccessible(nsINode* aNode, LocalAccessible* aContext,
bool* aIsSubtreeHidden = nullptr);
mozilla::a11y::role MarkupRole(const nsIContent* aContent) const {
const mozilla::a11y::MarkupMapInfo* markupMap =
GetMarkupMapInfoFor(aContent);
return markupMap ? markupMap->role : mozilla::a11y::roles::NOTHING;
}
/**
* Return the associated value for a given attribute if
* it appears in the MarkupMap. Otherwise, it returns null. This can be
* called with either an nsIContent or an Accessible.
*/
template <typename T>
nsStaticAtom* MarkupAttribute(T aSource, nsStaticAtom* aAtom) const {
const mozilla::a11y::MarkupMapInfo* markupMap =
GetMarkupMapInfoFor(aSource);
if (markupMap) {
for (size_t i = 0; i < std::size(markupMap->attrs); i++) {
const mozilla::a11y::MarkupAttrInfo* info = markupMap->attrs + i;
if (info->name == aAtom) {
return info->value;
}
}
}
return nullptr;
}
/**
* Set the object attribute defined by markup for the given element.
*/
void MarkupAttributes(mozilla::a11y::Accessible* aAcc,
mozilla::a11y::AccAttributes* aAttributes) const;
/**
* A list of possible accessibility service consumers. Accessibility service
* can only be shut down when there are no remaining consumers.
*
* eXPCOM - accessibility service is used by XPCOM.
*
* eMainProcess - accessibility service was started by main process in the
* content process.
*
* ePlatformAPI - accessibility service is used by the platform api in the
* main process.
*/
enum ServiceConsumer {
eXPCOM = 1 << 0,
eMainProcess = 1 << 1,
ePlatformAPI = 1 << 2,
};
static uint64_t GetActiveCacheDomains() { return gCacheDomains; }
#if defined(ANDROID)
static mozilla::Monitor& GetAndroidMonitor();
#endif
private:
// nsAccessibilityService creation is controlled by friend
// GetOrCreateAccService, keep constructors private.
nsAccessibilityService();
nsAccessibilityService(const nsAccessibilityService&);
nsAccessibilityService& operator=(const nsAccessibilityService&);
private:
/**
* Initialize accessibility service.
*/
bool Init(uint64_t aCacheDomains = kDefaultCacheDomains);
/**
* Shutdowns accessibility service.
*/
void Shutdown();
/**
* Create an accessible whose type depends on the given frame.
*/
already_AddRefed<LocalAccessible> CreateAccessibleByFrameType(
nsIFrame* aFrame, nsIContent* aContent, LocalAccessible* aContext);
/**
* Notify observers about change of the accessibility service's consumers.
*/
void NotifyOfConsumersChange();
/**
* Get a JSON string representing the accessibility service consumers.
*/
void GetConsumers(nsAString& aString);
/**
* Set accessibility service consumers.
*/
void SetConsumers(uint32_t aConsumers, bool aNotify = true);
/**
* Unset accessibility service consumers.
*/
void UnsetConsumers(uint32_t aConsumers);
/**
* Reference for accessibility service instance.
*/
static nsAccessibilityService* gAccessibilityService;
/**
* Reference for application accessible instance.
*/
static mozilla::a11y::ApplicationAccessible* gApplicationAccessible;
static mozilla::a11y::xpcAccessibleApplication* gXPCApplicationAccessible;
/**
* Contains a set of accessibility service consumers.
*/
static uint32_t gConsumers;
/**
* Contains the currently active cache domains.
*/
static uint64_t gCacheDomains;
// Can be weak because all atoms are known static
using MarkupMap = nsTHashMap<nsAtom*, const mozilla::a11y::MarkupMapInfo*>;
MarkupMap mHTMLMarkupMap;
MarkupMap mMathMLMarkupMap;
const mozilla::a11y::MarkupMapInfo* GetMarkupMapInfoFor(
const nsIContent* aContent) const {
if (aContent->IsHTMLElement()) {
return mHTMLMarkupMap.Get(aContent->NodeInfo()->NameAtom());
}
if (aContent->IsMathMLElement()) {
return mMathMLMarkupMap.Get(aContent->NodeInfo()->NameAtom());
}
// This function can be called by MarkupAttribute, etc. which might in turn
// be called on a XUL, SVG, etc. element. For example, this can happen
// with nsAccUtils::SetLiveContainerAttributes.
return nullptr;
}
const mozilla::a11y::MarkupMapInfo* GetMarkupMapInfoFor(
mozilla::a11y::Accessible* aAcc) const;
nsTHashMap<nsAtom*, const mozilla::a11y::XULMarkupMapInfo*> mXULMarkupMap;
friend nsAccessibilityService* GetAccService();
friend nsAccessibilityService* GetOrCreateAccService(uint32_t, uint64_t);
friend void MaybeShutdownAccService(uint32_t);
friend void mozilla::a11y::PrefChanged(const char*, void*);
friend mozilla::a11y::FocusManager* mozilla::a11y::FocusMgr();
friend mozilla::a11y::SelectionManager* mozilla::a11y::SelectionMgr();
friend mozilla::a11y::ApplicationAccessible* mozilla::a11y::ApplicationAcc();
friend mozilla::a11y::xpcAccessibleApplication*
mozilla::a11y::XPCApplicationAcc();
friend class xpcAccessibilityService;
};
/**
* Return the accessibility service instance. (Handy global function)
*/
inline nsAccessibilityService* GetAccService() {
return nsAccessibilityService::gAccessibilityService;
}
/**
* Return accessibility service instance; creating one if necessary.
*/
nsAccessibilityService* GetOrCreateAccService(
uint32_t aNewConsumer = nsAccessibilityService::ePlatformAPI,
uint64_t aCacheDomains = nsAccessibilityService::GetActiveCacheDomains());
/**
* Shutdown accessibility service if needed.
*/
void MaybeShutdownAccService(uint32_t aFormerConsumer);
/**
* Return true if we're in a content process and not B2G.
*/
inline bool IPCAccessibilityActive() { return XRE_IsContentProcess(); }
/**
* Map nsIAccessibleEvents constants to strings. Used by
* nsAccessibilityService::GetStringEventType() method.
*/
static const char kEventTypeNames[][40] = {
"unknown", //
"show", // EVENT_SHOW
"hide", // EVENT_HIDE
"reorder", // EVENT_REORDER
"focus", // EVENT_FOCUS
"state change", // EVENT_STATE_CHANGE
"name changed", // EVENT_NAME_CHANGE
"description change", // EVENT_DESCRIPTION_CHANGE
"value change", // EVENT_VALUE_CHANGE
"selection", // EVENT_SELECTION
"selection add", // EVENT_SELECTION_ADD
"selection remove", // EVENT_SELECTION_REMOVE
"selection within", // EVENT_SELECTION_WITHIN
"alert", // EVENT_ALERT
"menu start", // EVENT_MENU_START
"menu end", // EVENT_MENU_END
"menupopup start", // EVENT_MENUPOPUP_START
"menupopup end", // EVENT_MENUPOPUP_END
"dragdrop start", // EVENT_DRAGDROP_START
"scrolling start", // EVENT_SCROLLING_START
"scrolling end", // EVENT_SCROLLING_END
"document load complete", // EVENT_DOCUMENT_LOAD_COMPLETE
"document reload", // EVENT_DOCUMENT_RELOAD
"document load stopped", // EVENT_DOCUMENT_LOAD_STOPPED
"text attribute changed", // EVENT_TEXT_ATTRIBUTE_CHANGED
"text caret moved", // EVENT_TEXT_CARET_MOVED
"text inserted", // EVENT_TEXT_INSERTED
"text removed", // EVENT_TEXT_REMOVED
"text selection changed", // EVENT_TEXT_SELECTION_CHANGED
"window activate", // EVENT_WINDOW_ACTIVATE
"window deactivate", // EVENT_WINDOW_DEACTIVATE
"window maximize", // EVENT_WINDOW_MAXIMIZE
"window minimize", // EVENT_WINDOW_MINIMIZE
"window restore", // EVENT_WINDOW_RESTORE
"object attribute changed", // EVENT_OBJECT_ATTRIBUTE_CHANGED
"text value change", // EVENT_TEXT_VALUE_CHANGE
"scrolling", // EVENT_SCROLLING
"announcement", // EVENT_ANNOUNCEMENT
"live region added", // EVENT_LIVE_REGION_ADDED
"live region removed", // EVENT_LIVE_REGION_REMOVED
"inner reorder", // EVENT_INNER_REORDER
"live region changed", // EVENT_LIVE_REGION_CHANGED
};
#endif