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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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_a11y_DocAccessible_h__
#define mozilla_a11y_DocAccessible_h__
#include "nsIAccessibleDocument.h"
#include "nsIAccessiblePivot.h"
#include "AccEvent.h"
#include "HyperTextAccessibleWrap.h"
#include "nsClassHashtable.h"
#include "nsDataHashtable.h"
#include "nsIDocument.h"
#include "nsIDocumentObserver.h"
#include "nsIEditor.h"
#include "nsIObserver.h"
#include "nsIScrollPositionListener.h"
#include "nsITimer.h"
#include "nsIWeakReference.h"
#include "nsIDocShellTreeNode.h"
class nsAccessiblePivot;
class nsIScrollableView;
const uint32_t kDefaultCacheSize = 256;
namespace mozilla {
namespace a11y {
class DocManager;
class NotificationController;
class RelatedAccIterator;
template<class Class, class Arg>
class TNotification;
class DocAccessible : public HyperTextAccessibleWrap,
public nsIAccessibleDocument,
public nsIDocumentObserver,
public nsIObserver,
public nsIScrollPositionListener,
public nsSupportsWeakReference,
public nsIAccessiblePivotObserver
{
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(DocAccessible, Accessible)
NS_DECL_NSIACCESSIBLEDOCUMENT
NS_DECL_NSIOBSERVER
NS_DECL_NSIACCESSIBLEPIVOTOBSERVER
public:
DocAccessible(nsIDocument* aDocument, nsIContent* aRootContent,
nsIPresShell* aPresShell);
virtual ~DocAccessible();
// nsIAccessible
NS_IMETHOD TakeFocus(void);
// nsIScrollPositionListener
virtual void ScrollPositionWillChange(nscoord aX, nscoord aY) {}
virtual void ScrollPositionDidChange(nscoord aX, nscoord aY);
// nsIDocumentObserver
NS_DECL_NSIDOCUMENTOBSERVER
// nsAccessNode
virtual void Init();
virtual void Shutdown();
virtual nsIFrame* GetFrame() const;
virtual nsINode* GetNode() const { return mDocumentNode; }
nsIDocument* DocumentNode() const { return mDocumentNode; }
// Accessible
virtual mozilla::a11y::ENameValueFlag Name(nsString& aName);
virtual void Description(nsString& aDescription);
virtual Accessible* FocusedChild();
virtual mozilla::a11y::role NativeRole();
virtual uint64_t NativeState();
virtual uint64_t NativeInteractiveState() const;
virtual bool NativelyUnavailable() const;
virtual void ApplyARIAState(uint64_t* aState) const;
virtual already_AddRefed<nsIPersistentProperties> Attributes();
#ifdef A11Y_LOG
virtual nsresult HandleAccEvent(AccEvent* aEvent);
#endif
virtual void GetBoundsRect(nsRect& aRect, nsIFrame** aRelativeFrame);
// HyperTextAccessible
virtual already_AddRefed<nsIEditor> GetEditor() const;
// DocAccessible
/**
* Return presentation shell for this document accessible.
*/
nsIPresShell* PresShell() const { return mPresShell; }
/**
* Return the presentation shell's context.
*/
nsPresContext* PresContext() const { return mPresShell->GetPresContext(); }
/**
* Return true if associated DOM document was loaded and isn't unloading.
*/
bool IsContentLoaded() const
{
// eDOMLoaded flag check is used for error pages as workaround to make this
// method return correct result since error pages do not receive 'pageshow'
// event and as consequence nsIDocument::IsShowing() returns false.
return mDocumentNode && mDocumentNode->IsVisible() &&
(mDocumentNode->IsShowing() || HasLoadState(eDOMLoaded));
}
/**
* Document load states.
*/
enum LoadState {
// initial tree construction is pending
eTreeConstructionPending = 0,
// initial tree construction done
eTreeConstructed = 1,
// DOM document is loaded.
eDOMLoaded = 1 << 1,
// document is ready
eReady = eTreeConstructed | eDOMLoaded,
// document and all its subdocuments are ready
eCompletelyLoaded = eReady | 1 << 2
};
/**
* Return true if the document has given document state.
*/
bool HasLoadState(LoadState aState) const
{ return (mLoadState & static_cast<uint32_t>(aState)) ==
static_cast<uint32_t>(aState); }
/**
* Return a native window handler or pointer depending on platform.
*/
virtual void* GetNativeWindow() const;
/**
* Return the parent document.
*/
DocAccessible* ParentDocument() const
{ return mParent ? mParent->Document() : nullptr; }
/**
* Return the child document count.
*/
uint32_t ChildDocumentCount() const
{ return mChildDocuments.Length(); }
/**
* Return the child document at the given index.
*/
DocAccessible* GetChildDocumentAt(uint32_t aIndex) const
{ return mChildDocuments.SafeElementAt(aIndex, nullptr); }
/**
* Fire accessible event asynchronously.
*/
void FireDelayedEvent(AccEvent* aEvent);
void FireDelayedEvent(uint32_t aEventType, Accessible* aTarget);
/**
* Fire value change event on the given accessible if applicable.
*/
void MaybeNotifyOfValueChange(Accessible* aAccessible);
/**
* Get/set the anchor jump.
*/
Accessible* AnchorJump()
{ return GetAccessibleOrContainer(mAnchorJumpElm); }
void SetAnchorJump(nsIContent* aTargetNode)
{ mAnchorJumpElm = aTargetNode; }
/**
* Bind the child document to the tree.
*/
void BindChildDocument(DocAccessible* aDocument);
/**
* Process the generic notification.
*
* @note The caller must guarantee that the given instance still exists when
* notification is processed.
* @see NotificationController::HandleNotification
*/
template<class Class, class Arg>
void HandleNotification(Class* aInstance,
typename TNotification<Class, Arg>::Callback aMethod,
Arg* aArg);
/**
* Return the cached accessible by the given DOM node if it's in subtree of
* this document accessible or the document accessible itself, otherwise null.
*
* @return the accessible object
*/
Accessible* GetAccessible(nsINode* aNode) const;
/**
* Return whether the given DOM node has an accessible or not.
*/
bool HasAccessible(nsINode* aNode) const
{ return GetAccessible(aNode); }
/**
* Return the cached accessible by the given unique ID within this document.
*
* @note the unique ID matches with the uniqueID() of nsAccessNode
*
* @param aUniqueID [in] the unique ID used to cache the node.
*/
Accessible* GetAccessibleByUniqueID(void* aUniqueID)
{
return UniqueID() == aUniqueID ?
this : mAccessibleCache.GetWeak(aUniqueID);
}
/**
* Return the cached accessible by the given unique ID looking through
* this and nested documents.
*/
Accessible* GetAccessibleByUniqueIDInSubtree(void* aUniqueID);
/**
* Return an accessible for the given DOM node or container accessible if
* the node is not accessible.
*/
Accessible* GetAccessibleOrContainer(nsINode* aNode);
/**
* Return a container accessible for the given DOM node.
*/
Accessible* GetContainerAccessible(nsINode* aNode)
{
return aNode ? GetAccessibleOrContainer(aNode->GetParentNode()) : nullptr;
}
/**
* Return true if the given ID is referred by relation attribute.
*
* @note Different elements may share the same ID if they are hosted inside
* XBL bindings. Be careful the result of this method may be senseless
* while it's called for XUL elements (where XBL is used widely).
*/
bool IsDependentID(const nsAString& aID) const
{ return mDependentIDsHash.Get(aID, nullptr); }
/**
* Initialize the newly created accessible and put it into document caches.
*
* @param aAccessible [in] created accessible
* @param aRoleMapEntry [in] the role map entry role the ARIA role or nullptr
* if none
*/
bool BindToDocument(Accessible* aAccessible, nsRoleMapEntry* aRoleMapEntry);
/**
* Remove from document and shutdown the given accessible.
*/
void UnbindFromDocument(Accessible* aAccessible);
/**
* Notify the document accessible that content was inserted.
*/
void ContentInserted(nsIContent* aContainerNode,
nsIContent* aStartChildNode,
nsIContent* aEndChildNode);
/**
* Notify the document accessible that content was removed.
*/
void ContentRemoved(nsIContent* aContainerNode, nsIContent* aChildNode);
/**
* Updates accessible tree when rendered text is changed.
*/
void UpdateText(nsIContent* aTextNode);
/**
* Recreate an accessible, results in hide/show events pair.
*/
void RecreateAccessible(nsIContent* aContent);
protected:
void LastRelease();
// Accessible
virtual void CacheChildren();
// DocAccessible
virtual nsresult AddEventListeners();
virtual nsresult RemoveEventListeners();
/**
* Marks this document as loaded or loading.
*/
void NotifyOfLoad(uint32_t aLoadEventType);
void NotifyOfLoading(bool aIsReloading);
friend class DocManager;
/**
* Perform initial update (create accessible tree).
* Can be overridden by wrappers to prepare initialization work.
*/
virtual void DoInitialUpdate();
/**
* Process document load notification, fire document load and state busy
* events if applicable.
*/
void ProcessLoad();
/**
* Add/remove scroll listeners, @see nsIScrollPositionListener interface.
*/
void AddScrollListener();
void RemoveScrollListener();
/**
* Append the given document accessible to this document's child document
* accessibles.
*/
bool AppendChildDocument(DocAccessible* aChildDocument)
{
return mChildDocuments.AppendElement(aChildDocument);
}
/**
* Remove the given document accessible from this document's child document
* accessibles.
*/
void RemoveChildDocument(DocAccessible* aChildDocument)
{
mChildDocuments.RemoveElement(aChildDocument);
}
/**
* Add dependent IDs pointed by accessible element by relation attribute to
* cache. If the relation attribute is missed then all relation attributes
* are checked.
*
* @param aRelProvider [in] accessible that element has relation attribute
* @param aRelAttr [in, optional] relation attribute
*/
void AddDependentIDsFor(dom::Element* aRelProviderElm,
nsIAtom* aRelAttr = nullptr);
/**
* Remove dependent IDs pointed by accessible element by relation attribute
* from cache. If the relation attribute is absent then all relation
* attributes are checked.
*
* @param aRelProvider [in] accessible that element has relation attribute
* @param aRelAttr [in, optional] relation attribute
*/
void RemoveDependentIDsFor(dom::Element* aRelProviderElm,
nsIAtom* aRelAttr = nullptr);
/**
* Update or recreate an accessible depending on a changed attribute.
*
* @param aElement [in] the element the attribute was changed on
* @param aAttribute [in] the changed attribute
* @return true if an action was taken on the attribute change
*/
bool UpdateAccessibleOnAttrChange(mozilla::dom::Element* aElement,
nsIAtom* aAttribute);
/**
* Fire accessible events when attribute is changed.
*
* @param aAccessible [in] accessible the DOM attribute is changed for
* @param aNameSpaceID [in] namespace of changed attribute
* @param aAttribute [in] changed attribute
*/
void AttributeChangedImpl(Accessible* aAccessible,
int32_t aNameSpaceID, nsIAtom* aAttribute);
/**
* Fire accessible events when ARIA attribute is changed.
*
* @param aAccessible [in] accesislbe the DOM attribute is changed for
* @param aAttribute [in] changed attribute
*/
void ARIAAttributeChanged(Accessible* aAccessible, nsIAtom* aAttribute);
/**
* Process ARIA active-descendant attribute change.
*/
void ARIAActiveDescendantChanged(Accessible* aAccessible);
/**
* Update the accessible tree for inserted content.
*/
void ProcessContentInserted(Accessible* aContainer,
const nsTArray<nsCOMPtr<nsIContent> >* aInsertedContent);
/**
* Used to notify the document to make it process the invalidation list.
*
* While children are cached we may encounter the case there's no accessible
* for referred content by related accessible. Store these related nodes to
* invalidate their containers later.
*/
void ProcessInvalidationList();
/**
* Update the accessible tree for content insertion or removal.
*/
void UpdateTree(Accessible* aContainer, nsIContent* aChildNode,
bool aIsInsert);
/**
* Helper for UpdateTree() method. Go down to DOM subtree and updates
* accessible tree. Return one of these flags.
*/
enum EUpdateTreeFlags {
eNoAccessible = 0,
eAccessible = 1,
eAlertAccessible = 2
};
uint32_t UpdateTreeInternal(Accessible* aChild, bool aIsInsert,
AccReorderEvent* aReorderEvent);
/**
* Create accessible tree.
*/
void CacheChildrenInSubtree(Accessible* aRoot);
/**
* Remove accessibles in subtree from node to accessible map.
*/
void UncacheChildrenInSubtree(Accessible* aRoot);
/**
* Shutdown any cached accessible in the subtree.
*
* @param aAccessible [in] the root of the subrtee to invalidate accessible
* child/parent refs in
*/
void ShutdownChildrenInSubtree(Accessible* aAccessible);
/**
* Return true if the document is a target of document loading events
* (for example, state busy change or document reload events).
*
* Rules: The root chrome document accessible is never an event target
* (for example, Firefox UI window). If the sub document is loaded within its
* parent document then the parent document is a target only (aka events
* coalescence).
*/
bool IsLoadEventTarget() const;
/**
* Used to fire scrolling end event after page scroll.
*
* @param aTimer [in] the timer object
* @param aClosure [in] the document accessible where scrolling happens
*/
static void ScrollTimerCallback(nsITimer* aTimer, void* aClosure);
protected:
/**
* State and property flags, kept by mDocFlags.
*/
enum {
// Whether scroll listeners were added.
eScrollInitialized = 1 << 0,
// Whether the document is a tab document.
eTabDocument = 1 << 1
};
/**
* Cache of accessibles within this document accessible.
*/
AccessibleHashtable mAccessibleCache;
nsDataHashtable<nsPtrHashKey<const nsINode>, Accessible*>
mNodeToAccessibleMap;
nsIDocument* mDocumentNode;
nsCOMPtr<nsITimer> mScrollWatchTimer;
uint16_t mScrollPositionChangedTicks; // Used for tracking scroll events
/**
* Bit mask of document load states (@see LoadState).
*/
uint32_t mLoadState : 3;
/**
* Bit mask of other states and props.
*/
uint32_t mDocFlags : 28;
/**
* Type of document load event fired after the document is loaded completely.
*/
uint32_t mLoadEventType;
/**
* Reference to anchor jump element.
*/
nsCOMPtr<nsIContent> mAnchorJumpElm;
/**
* Keep the ARIA attribute old value that is initialized by
* AttributeWillChange and used by AttributeChanged notifications.
*/
nsIAtom* mARIAAttrOldValue;
nsTArray<nsRefPtr<DocAccessible> > mChildDocuments;
/**
* The virtual cursor of the document.
*/
nsRefPtr<nsAccessiblePivot> mVirtualCursor;
/**
* A storage class for pairing content with one of its relation attributes.
*/
class AttrRelProvider
{
public:
AttrRelProvider(nsIAtom* aRelAttr, nsIContent* aContent) :
mRelAttr(aRelAttr), mContent(aContent) { }
nsIAtom* mRelAttr;
nsCOMPtr<nsIContent> mContent;
private:
AttrRelProvider();
AttrRelProvider(const AttrRelProvider&);
AttrRelProvider& operator =(const AttrRelProvider&);
};
typedef nsTArray<nsAutoPtr<AttrRelProvider> > AttrRelProviderArray;
typedef nsClassHashtable<nsStringHashKey, AttrRelProviderArray>
DependentIDsHashtable;
/**
* The cache of IDs pointed by relation attributes.
*/
DependentIDsHashtable mDependentIDsHash;
static PLDHashOperator
CycleCollectorTraverseDepIDsEntry(const nsAString& aKey,
AttrRelProviderArray* aProviders,
void* aUserArg);
friend class RelatedAccIterator;
/**
* Used for our caching algorithm. We store the list of nodes that should be
* invalidated.
*
* @see ProcessInvalidationList
*/
nsTArray<nsIContent*> mInvalidationList;
/**
* Used to process notification from core and accessible events.
*/
nsRefPtr<NotificationController> mNotificationController;
friend class EventQueue;
friend class NotificationController;
private:
nsIPresShell* mPresShell;
};
inline DocAccessible*
Accessible::AsDoc()
{
return IsDoc() ? static_cast<DocAccessible*>(this) : nullptr;
}
} // namespace a11y
} // namespace mozilla
#endif

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