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| -rw-r--r-- | accessible/generic/LocalAccessible.h | 1066 |
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diff --git a/accessible/generic/LocalAccessible.h b/accessible/generic/LocalAccessible.h new file mode 100644 index 0000000000..173cb41cab --- /dev/null +++ b/accessible/generic/LocalAccessible.h @@ -0,0 +1,1066 @@ +/* -*- 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 _LocalAccessible_H_ +#define _LocalAccessible_H_ + +#include "mozilla/ComputedStyle.h" +#include "mozilla/a11y/Accessible.h" +#include "mozilla/a11y/AccTypes.h" +#include "mozilla/a11y/RelationType.h" +#include "mozilla/a11y/States.h" + +#include "mozilla/UniquePtr.h" + +#include "nsIContent.h" +#include "nsTArray.h" +#include "nsRefPtrHashtable.h" +#include "nsRect.h" + +struct nsRoleMapEntry; + +class nsIFrame; + +class nsAttrValue; + +namespace mozilla::dom { +class Element; +} + +namespace mozilla { +namespace a11y { + +class LocalAccessible; +class AccAttributes; +class AccEvent; +class AccGroupInfo; +class ApplicationAccessible; +class CacheData; +class DocAccessible; +class EmbeddedObjCollector; +class EventTree; +class HTMLImageMapAccessible; +class HTMLLIAccessible; +class HTMLLinkAccessible; +class HyperTextAccessible; +class HyperTextAccessibleBase; +class ImageAccessible; +class KeyBinding; +class OuterDocAccessible; +class RemoteAccessible; +class Relation; +class RootAccessible; +class TableAccessible; +class TableAccessibleBase; +class TableCellAccessible; +class TableCellAccessibleBase; +class TextLeafAccessible; +class XULLabelAccessible; +class XULTreeAccessible; + +enum class CacheUpdateType; + +#ifdef A11Y_LOG +namespace logging { +typedef const char* (*GetTreePrefix)(void* aData, LocalAccessible*); +void Tree(const char* aTitle, const char* aMsgText, LocalAccessible* aRoot, + GetTreePrefix aPrefixFunc, void* GetTreePrefixData); +void TreeSize(const char* aTitle, const char* aMsgText, LocalAccessible* aRoot); +}; // namespace logging +#endif + +typedef nsRefPtrHashtable<nsPtrHashKey<const void>, LocalAccessible> + AccessibleHashtable; + +#define NS_ACCESSIBLE_IMPL_IID \ + { /* 133c8bf4-4913-4355-bd50-426bd1d6e1ad */ \ + 0x133c8bf4, 0x4913, 0x4355, { \ + 0xbd, 0x50, 0x42, 0x6b, 0xd1, 0xd6, 0xe1, 0xad \ + } \ + } + +/** + * An accessibility tree node that originated in mDoc's content process. + */ +class LocalAccessible : public nsISupports, public Accessible { + public: + LocalAccessible(nsIContent* aContent, DocAccessible* aDoc); + + NS_DECL_CYCLE_COLLECTING_ISUPPORTS + NS_DECL_CYCLE_COLLECTION_CLASS(LocalAccessible) + + NS_DECLARE_STATIC_IID_ACCESSOR(NS_ACCESSIBLE_IMPL_IID) + + ////////////////////////////////////////////////////////////////////////////// + // Public methods + + /** + * Return the document accessible for this accessible. + */ + DocAccessible* Document() const { return mDoc; } + + /** + * Return the root document accessible for this accessible. + */ + a11y::RootAccessible* RootAccessible() const; + + /** + * Return frame for this accessible. + * Note that this will return null for display: contents. Also, + * DocAccessible::GetFrame can return null if the frame tree hasn't been + * created yet. + */ + virtual nsIFrame* GetFrame() const; + + /** + * Return DOM node associated with the accessible. + */ + virtual nsINode* GetNode() const; + + nsIContent* GetContent() const { return mContent; } + dom::Element* Elm() const; + + /** + * Return node type information of DOM node associated with the accessible. + */ + bool IsContent() const { return GetNode() && GetNode()->IsContent(); } + + /** + * Return the unique identifier of the accessible. + * ID() should be preferred, but this method still exists because many + * LocalAccessible callers expect a void*. + */ + void* UniqueID() { return static_cast<void*>(this); } + + virtual uint64_t ID() const override { + return IsDoc() ? 0 : reinterpret_cast<uintptr_t>(this); + } + + /** + * Return language associated with the accessible. + */ + void Language(nsAString& aLocale); + + /** + * Get the description of this accessible. + */ + virtual void Description(nsString& aDescription) const override; + + /** + * Get the value of this accessible. + */ + virtual void Value(nsString& aValue) const override; + + /** + * Get help string for the accessible. + */ + void Help(nsString& aHelp) const { aHelp.Truncate(); } + + /** + * Get the name of this accessible. + */ + virtual ENameValueFlag Name(nsString& aName) const override; + + /** + * Maps ARIA state attributes to state of accessible. Note the given state + * argument should hold states for accessible before you pass it into this + * method. + * + * @param [in/out] where to fill the states into. + */ + virtual void ApplyARIAState(uint64_t* aState) const; + + /** + * Return enumerated accessible role (see constants in Role.h). + */ + virtual mozilla::a11y::role Role() const override; + + /** + * Return accessible role specified by ARIA (see constants in + * roles). + */ + mozilla::a11y::role ARIARole(); + + /** + * Returns enumerated accessible role from native markup (see constants in + * Role.h). Doesn't take into account ARIA roles. + */ + virtual mozilla::a11y::role NativeRole() const; + + virtual uint64_t State() override; + + /** + * Return interactive states present on the accessible + * (@see NativeInteractiveState). + */ + uint64_t InteractiveState() const { + uint64_t state = NativeInteractiveState(); + ApplyARIAState(&state); + return state; + } + + /** + * Return link states present on the accessible. + */ + uint64_t LinkState() const { + uint64_t state = NativeLinkState(); + ApplyARIAState(&state); + return state; + } + + /** + * Return the states of accessible, not taking into account ARIA states. + * Use State() to get complete set of states. + */ + virtual uint64_t NativeState() const; + + /** + * Return native interactice state (unavailable, focusable or selectable). + */ + virtual uint64_t NativeInteractiveState() const; + + /** + * Return native link states present on the accessible. + */ + virtual uint64_t NativeLinkState() const; + + /** + * Return bit set of invisible and offscreen states. + */ + uint64_t VisibilityState() const; + + /** + * Return true if native unavailable state present. + */ + virtual bool NativelyUnavailable() const; + + virtual already_AddRefed<AccAttributes> Attributes() override; + + /** + * Return direct or deepest child at the given point. + * + * @param aX [in] x coordinate relative screen + * @param aY [in] y coordinate relative screen + * @param aWhichChild [in] flag points if deepest or direct child + * should be returned + */ + virtual LocalAccessible* LocalChildAtPoint(int32_t aX, int32_t aY, + EWhichChildAtPoint aWhichChild); + + /** + * Similar to LocalChildAtPoint but crosses process boundaries. + */ + virtual Accessible* ChildAtPoint(int32_t aX, int32_t aY, + EWhichChildAtPoint aWhichChild) override; + + virtual Relation RelationByType(RelationType aType) const override; + + ////////////////////////////////////////////////////////////////////////////// + // Initializing methods + + /** + * Shutdown this accessible object. + */ + virtual void Shutdown(); + + /** + * Set the ARIA role map entry for a new accessible. + */ + void SetRoleMapEntry(const nsRoleMapEntry* aRoleMapEntry); + + /** + * Append/insert/remove a child. Return true if operation was successful. + */ + bool AppendChild(LocalAccessible* aChild) { + return InsertChildAt(mChildren.Length(), aChild); + } + virtual bool InsertChildAt(uint32_t aIndex, LocalAccessible* aChild); + + /** + * Inserts a child after given sibling. If the child cannot be inserted, + * then the child is unbound from the document, and false is returned. Make + * sure to null out any references on the child object as it may be destroyed. + */ + bool InsertAfter(LocalAccessible* aNewChild, LocalAccessible* aRefChild); + + virtual bool RemoveChild(LocalAccessible* aChild); + + /** + * Reallocates the child within its parent. + */ + virtual void RelocateChild(uint32_t aNewIndex, LocalAccessible* aChild); + + // Accessible hierarchy method overrides + + virtual Accessible* Parent() const override { return LocalParent(); } + + virtual Accessible* ChildAt(uint32_t aIndex) const override { + return LocalChildAt(aIndex); + } + + virtual Accessible* NextSibling() const override { + return LocalNextSibling(); + } + + virtual Accessible* PrevSibling() const override { + return LocalPrevSibling(); + } + + ////////////////////////////////////////////////////////////////////////////// + // LocalAccessible tree traverse methods + + /** + * Return parent accessible. + */ + LocalAccessible* LocalParent() const { return mParent; } + + /** + * Return child accessible at the given index. + */ + virtual LocalAccessible* LocalChildAt(uint32_t aIndex) const; + + /** + * Return child accessible count. + */ + virtual uint32_t ChildCount() const override; + + /** + * Return index of the given child accessible. + */ + int32_t GetIndexOf(const LocalAccessible* aChild) const { + return (aChild->mParent != this) ? -1 : aChild->IndexInParent(); + } + + /** + * Return index in parent accessible. + */ + virtual int32_t IndexInParent() const override; + + /** + * Return first/last/next/previous sibling of the accessible. + */ + inline LocalAccessible* LocalNextSibling() const { + return GetSiblingAtOffset(1); + } + inline LocalAccessible* LocalPrevSibling() const { + return GetSiblingAtOffset(-1); + } + inline LocalAccessible* LocalFirstChild() const { return LocalChildAt(0); } + inline LocalAccessible* LocalLastChild() const { + uint32_t childCount = ChildCount(); + return childCount != 0 ? LocalChildAt(childCount - 1) : nullptr; + } + + virtual uint32_t EmbeddedChildCount() override; + + /** + * Return embedded accessible child at the given index. + */ + virtual LocalAccessible* EmbeddedChildAt(uint32_t aIndex) override; + + virtual int32_t IndexOfEmbeddedChild(Accessible* aChild) override; + + /** + * Return number of content children/content child at index. The content + * child is created from markup in contrast to it's never constructed by its + * parent accessible (like treeitem accessibles for XUL trees). + */ + uint32_t ContentChildCount() const { return mChildren.Length(); } + LocalAccessible* ContentChildAt(uint32_t aIndex) const { + return mChildren.ElementAt(aIndex); + } + + /** + * Return true if the accessible is attached to tree. + */ + bool IsBoundToParent() const { return !!mParent; } + + ////////////////////////////////////////////////////////////////////////////// + // Miscellaneous methods + + /** + * Handle accessible event, i.e. process it, notifies observers and fires + * platform specific event. + */ + virtual nsresult HandleAccEvent(AccEvent* aAccEvent); + + /** + * Return true if the accessible is an acceptable child. + */ + virtual bool IsAcceptableChild(nsIContent* aEl) const { + return aEl && + !aEl->IsAnyOfHTMLElements(nsGkAtoms::option, nsGkAtoms::optgroup); + } + + virtual void AppendTextTo(nsAString& aText, uint32_t aStartOffset = 0, + uint32_t aLength = UINT32_MAX) override; + + virtual nsRect BoundsInAppUnits() const override; + + virtual LayoutDeviceIntRect Bounds() const override; + + /** + * Return boundaries rect relative the bounding frame. + */ + virtual nsRect RelativeBounds(nsIFrame** aRelativeFrame) const; + + /** + * Return boundaries rect relative to the frame of the parent accessible. + * The returned bounds are the same regardless of whether the parent is + * scrolled. This means the scroll position must be later subtracted to + * calculate absolute coordinates. + */ + virtual nsRect ParentRelativeBounds(); + + /** + * Selects the accessible within its container if applicable. + */ + virtual void SetSelected(bool aSelect) override; + + /** + * Select the accessible within its container. + */ + virtual void TakeSelection() override; + + /** + * Focus the accessible. + */ + MOZ_CAN_RUN_SCRIPT_BOUNDARY virtual void TakeFocus() const override; + + MOZ_CAN_RUN_SCRIPT + virtual void ScrollTo(uint32_t aHow) const override; + + /** + * Scroll the accessible to the given point. + */ + void ScrollToPoint(uint32_t aCoordinateType, int32_t aX, int32_t aY); + + /** + * Get a pointer to accessibility interface for this node, which is specific + * to the OS/accessibility toolkit we're running on. + */ + virtual void GetNativeInterface(void** aNativeAccessible); + + virtual Maybe<int32_t> GetIntARIAAttr(nsAtom* aAttrName) const override; + + ////////////////////////////////////////////////////////////////////////////// + // Downcasting and types + + inline bool IsAbbreviation() const { + return mContent && + mContent->IsAnyOfHTMLElements(nsGkAtoms::abbr, nsGkAtoms::acronym); + } + + ApplicationAccessible* AsApplication(); + + DocAccessible* AsDoc(); + + HyperTextAccessible* AsHyperText(); + virtual HyperTextAccessibleBase* AsHyperTextBase() override; + + HTMLLIAccessible* AsHTMLListItem(); + + HTMLLinkAccessible* AsHTMLLink(); + + ImageAccessible* AsImage(); + + HTMLImageMapAccessible* AsImageMap(); + + OuterDocAccessible* AsOuterDoc(); + + a11y::RootAccessible* AsRoot(); + + bool IsSearchbox() const; + + virtual TableAccessible* AsTable() { return nullptr; } + + virtual TableCellAccessible* AsTableCell() { return nullptr; } + const TableCellAccessible* AsTableCell() const { + return const_cast<LocalAccessible*>(this)->AsTableCell(); + } + + virtual TableAccessibleBase* AsTableBase() override; + virtual TableCellAccessibleBase* AsTableCellBase() override; + + TextLeafAccessible* AsTextLeaf(); + + XULLabelAccessible* AsXULLabel(); + + XULTreeAccessible* AsXULTree(); + + ////////////////////////////////////////////////////////////////////////////// + // ActionAccessible + + virtual bool HasPrimaryAction() const override; + + virtual uint8_t ActionCount() const override; + + virtual void ActionNameAt(uint8_t aIndex, nsAString& aName) override; + + virtual bool DoAction(uint8_t aIndex) const override; + + virtual KeyBinding AccessKey() const override; + + /** + * Return global keyboard shortcut for default action, such as Ctrl+O for + * Open file menuitem. + */ + virtual KeyBinding KeyboardShortcut() const; + + ////////////////////////////////////////////////////////////////////////////// + // HyperLinkAccessible (any embedded object in text can implement HyperLink, + // which helps determine where it is located within containing text). + + /** + * Return true if the accessible is hyper link accessible. + */ + virtual bool IsLink() const override; + + /** + * Return true if the link is valid (e. g. points to a valid URL). + */ + inline bool IsLinkValid() { + MOZ_ASSERT(IsLink(), "IsLinkValid is called on not hyper link!"); + + // XXX In order to implement this we would need to follow every link + // Perhaps we can get information about invalid links from the cache + // In the mean time authors can use role="link" aria-invalid="true" + // to force it for links they internally know to be invalid + return (0 == (State() & mozilla::a11y::states::INVALID)); + } + + /** + * Return the number of anchors within the link. + */ + virtual uint32_t AnchorCount(); + + /** + * Returns an anchor accessible at the given index. + */ + virtual LocalAccessible* AnchorAt(uint32_t aAnchorIndex); + + /** + * Returns an anchor URI at the given index. + */ + virtual already_AddRefed<nsIURI> AnchorURIAt(uint32_t aAnchorIndex) const; + + ////////////////////////////////////////////////////////////////////////////// + // SelectAccessible + + /** + * Return an array of selected items. + */ + virtual void SelectedItems(nsTArray<Accessible*>* aItems) override; + + /** + * Return the number of selected items. + */ + virtual uint32_t SelectedItemCount() override; + + /** + * Return selected item at the given index. + */ + virtual Accessible* GetSelectedItem(uint32_t aIndex) override; + + /** + * Determine if item at the given index is selected. + */ + virtual bool IsItemSelected(uint32_t aIndex) override; + + /** + * Add item at the given index the selection. Return true if success. + */ + virtual bool AddItemToSelection(uint32_t aIndex) override; + + /** + * Remove item at the given index from the selection. Return if success. + */ + virtual bool RemoveItemFromSelection(uint32_t aIndex) override; + + /** + * Select all items. Return true if success. + */ + virtual bool SelectAll() override; + + /** + * Unselect all items. Return true if success. + */ + virtual bool UnselectAll() override; + + ////////////////////////////////////////////////////////////////////////////// + // Value (numeric value interface) + + virtual double MaxValue() const override; + virtual double MinValue() const override; + virtual double CurValue() const override; + virtual double Step() const override; + virtual bool SetCurValue(double aValue); + + ////////////////////////////////////////////////////////////////////////////// + // Widgets + + /** + * Return true if accessible is a widget, i.e. control or accessible that + * manages its items. Note, being a widget the accessible may be a part of + * composite widget. + */ + virtual bool IsWidget() const; + + /** + * Return true if the widget is active, i.e. has a focus within it. + */ + virtual bool IsActiveWidget() const; + + /** + * Return true if the widget has items and items are operable by user and + * can be activated. + */ + virtual bool AreItemsOperable() const; + + /** + * Return the current item of the widget, i.e. an item that has or will have + * keyboard focus when widget gets active. + */ + virtual LocalAccessible* CurrentItem() const; + + /** + * Set the current item of the widget. + */ + virtual void SetCurrentItem(const LocalAccessible* aItem); + + /** + * Return container widget this accessible belongs to. + */ + virtual LocalAccessible* ContainerWidget() const; + + bool IsActiveDescendant(LocalAccessible** aWidget = nullptr) const; + + /** + * Return true if the accessible is defunct. + */ + bool IsDefunct() const; + + /** + * Return false if the accessible is no longer in the document. + */ + bool IsInDocument() const { return !(mStateFlags & eIsNotInDocument); } + + /** + * Return true if the accessible should be contained by document node map. + */ + bool IsNodeMapEntry() const { + return HasOwnContent() && !(mStateFlags & eNotNodeMapEntry); + } + + /** + * Return true if the accessible has associated DOM content. + */ + bool HasOwnContent() const { + return mContent && !(mStateFlags & eSharedNode); + } + + /** + * Return true if native markup has a numeric value. + */ + bool NativeHasNumericValue() const; + + /** + * Return true if ARIA specifies support for a numeric value. + */ + bool ARIAHasNumericValue() const; + + /** + * Return true if the accessible has a numeric value. + */ + virtual bool HasNumericValue() const override; + + /** + * Return true if the accessible state change is processed by handling proper + * DOM UI event, if otherwise then false. For example, CheckboxAccessible + * created for HTML:input@type="checkbox" will process + * nsIDocumentObserver::ElementStateChanged instead of 'CheckboxStateChange' + * event. + */ + bool NeedsDOMUIEvent() const { return !(mStateFlags & eIgnoreDOMUIEvent); } + + /** + * Get/set repositioned bit indicating that the accessible was moved in + * the accessible tree, i.e. the accessible tree structure differs from DOM. + */ + bool IsRelocated() const { return mStateFlags & eRelocated; } + void SetRelocated(bool aRelocated) { + if (aRelocated) { + mStateFlags |= eRelocated; + } else { + mStateFlags &= ~eRelocated; + } + } + + /** + * Return true if the accessible allows accessible children from subtree of + * a DOM element of this accessible. + */ + bool KidsFromDOM() const { return !(mStateFlags & eNoKidsFromDOM); } + + /** + * Return true if this accessible has a parent, relation or ancestor with a + * relation whose name depends on this accessible. + */ + bool HasNameDependent() const { return mContextFlags & eHasNameDependent; } + + /** + * Return true if this accessible has a parent, relation or ancestor with a + * relation whose description depends on this accessible. + */ + bool HasDescriptionDependent() const { + return mContextFlags & eHasDescriptionDependent; + } + + /** + * Return true if the element is inside an alert. + */ + bool IsInsideAlert() const { return mContextFlags & eInsideAlert; } + + /** + * Return true if there is a pending reorder event for this accessible. + */ + bool ReorderEventTarget() const { return mReorderEventTarget; } + + /** + * Return true if there is a pending show event for this accessible. + */ + bool ShowEventTarget() const { return mShowEventTarget; } + + /** + * Return true if there is a pending hide event for this accessible. + */ + bool HideEventTarget() const { return mHideEventTarget; } + + /** + * Set if there is a pending reorder event for this accessible. + */ + void SetReorderEventTarget(bool aTarget) { mReorderEventTarget = aTarget; } + + /** + * Set if this accessible is a show event target. + */ + void SetShowEventTarget(bool aTarget) { mShowEventTarget = aTarget; } + + /** + * Set if this accessible is a hide event target. + */ + void SetHideEventTarget(bool aTarget) { mHideEventTarget = aTarget; } + + void Announce(const nsAString& aAnnouncement, uint16_t aPriority); + + virtual bool IsRemote() const override { return false; } + + already_AddRefed<AccAttributes> BundleFieldsForCache( + uint64_t aCacheDomain, CacheUpdateType aUpdateType); + + /** + * Push fields to cache. + * aCacheDomain - describes which fields to bundle and ultimately send + * aUpdate - describes whether this is an initial or subsequent update + */ + void SendCache(uint64_t aCacheDomain, CacheUpdateType aUpdate); + + void MaybeQueueCacheUpdateForStyleChanges(); + + virtual nsAtom* TagName() const override; + + virtual already_AddRefed<nsAtom> DisplayStyle() const override; + + virtual float Opacity() const override; + + virtual void DOMNodeID(nsString& aID) const override; + + virtual void LiveRegionAttributes(nsAString* aLive, nsAString* aRelevant, + Maybe<bool>* aAtomic, + nsAString* aBusy) const override; + + virtual Maybe<bool> ARIASelected() const override; + + protected: + virtual ~LocalAccessible(); + + /** + * Return the accessible name provided by native markup. It doesn't take + * into account ARIA markup used to specify the name. + */ + virtual mozilla::a11y::ENameValueFlag NativeName(nsString& aName) const; + + /** + * Return the accessible description provided by native markup. It doesn't + * take into account ARIA markup used to specify the description. + */ + void NativeDescription(nsString& aDescription) const; + + /** + * Return object attributes provided by native markup. It doesn't take into + * account ARIA. + */ + virtual already_AddRefed<AccAttributes> NativeAttributes(); + + /** + * The given attribute has the potential of changing the accessible's state. + * This is used to capture the state before the attribute change and compare + * it with the state after. + */ + virtual bool AttributeChangesState(nsAtom* aAttribute); + + /** + * Notify accessible that a DOM attribute on its associated content has + * changed. This allows the accessible to update its state and emit any + * relevant events. + */ + virtual void DOMAttributeChanged(int32_t aNameSpaceID, nsAtom* aAttribute, + int32_t aModType, + const nsAttrValue* aOldValue, + uint64_t aOldState); + + ////////////////////////////////////////////////////////////////////////////// + // Initializing, cache and tree traverse methods + + /** + * Destroy the object. + */ + void LastRelease(); + + /** + * Set accessible parent and index in parent. + */ + void BindToParent(LocalAccessible* aParent, uint32_t aIndexInParent); + void UnbindFromParent(); + + /** + * Return sibling accessible at the given offset. + */ + virtual LocalAccessible* GetSiblingAtOffset(int32_t aOffset, + nsresult* aError = nullptr) const; + + void ModifySubtreeContextFlags(uint32_t aContextFlags, bool aAdd); + + /** + * Flags used to describe the state of this accessible. + */ + enum StateFlags { + eIsDefunct = 1 << 0, // accessible is defunct + eIsNotInDocument = 1 << 1, // accessible is not in document + eSharedNode = 1 << 2, // accessible shares DOM node from another accessible + eNotNodeMapEntry = 1 << 3, // accessible shouldn't be in document node map + eGroupInfoDirty = 1 << 4, // accessible needs to update group info + eKidsMutating = 1 << 5, // subtree is being mutated + eIgnoreDOMUIEvent = 1 << 6, // don't process DOM UI events for a11y events + eRelocated = 1 << 7, // accessible was moved in tree + eNoKidsFromDOM = 1 << 8, // accessible doesn't allow children from DOM + eHasTextKids = 1 << 9, // accessible have a text leaf in children + eOldFrameHasValidTransformStyle = + 1 << 10, // frame prior to most recent style change both has transform + // styling and supports transforms + + eLastStateFlag = eOldFrameHasValidTransformStyle + }; + + /** + * Flags used for contextual information about the accessible. + */ + enum ContextFlags { + eHasNameDependent = 1 << 0, // See HasNameDependent(). + eInsideAlert = 1 << 1, + eHasDescriptionDependent = 1 << 2, // See HasDescriptionDependent(). + + eLastContextFlag = eHasDescriptionDependent + }; + + protected: + ////////////////////////////////////////////////////////////////////////////// + // Miscellaneous helpers + + /** + * Return ARIA role (helper method). + */ + mozilla::a11y::role ARIATransformRole(mozilla::a11y::role aRole) const; + + ////////////////////////////////////////////////////////////////////////////// + // Name helpers + + /** + * Returns the accessible name specified by ARIA. + */ + void ARIAName(nsString& aName) const; + + /** + * Returns the accessible description specified by ARIA. + */ + void ARIADescription(nsString& aDescription) const; + + /** + * Returns the accessible name specified for this control using XUL + * <label control="id" ...>. + */ + static void NameFromAssociatedXULLabel(DocAccessible* aDocument, + nsIContent* aElm, nsString& aName); + + /** + * Return the name for XUL element. + */ + static void XULElmName(DocAccessible* aDocument, nsIContent* aElm, + nsString& aName); + + // helper method to verify frames + static nsresult GetFullKeyName(const nsAString& aModifierName, + const nsAString& aKeyName, + nsAString& aStringOut); + + ////////////////////////////////////////////////////////////////////////////// + // Action helpers + + /** + * Prepares click action that will be invoked in timeout. + * + * @note DoCommand() prepares an action in timeout because when action + * command opens a modal dialog/window, it won't return until the + * dialog/window is closed. If executing action command directly in + * nsIAccessible::DoAction() method, it will block AT tools (e.g. GOK) that + * invoke action of mozilla accessibles direclty (see bug 277888 for + * details). + * + * @param aContent [in, optional] element to click + * @param aActionIndex [in, optional] index of accessible action + */ + void DoCommand(nsIContent* aContent = nullptr, + uint32_t aActionIndex = 0) const; + + /** + * Dispatch click event. + */ + MOZ_CAN_RUN_SCRIPT + virtual void DispatchClickEvent(nsIContent* aContent, + uint32_t aActionIndex) const; + + ////////////////////////////////////////////////////////////////////////////// + // Helpers + + /** + * Get the container node for an atomic region, defined by aria-atomic="true" + * @return the container node + */ + nsIContent* GetAtomicRegion() const; + + /** + * Return numeric value of the given ARIA attribute, NaN if not applicable. + * + * @param aARIAProperty [in] the ARIA property we're using + * @return a numeric value + */ + double AttrNumericValue(nsAtom* aARIAAttr) const; + + /** + * Return the action rule based on ARIA enum constants EActionRule + * (see ARIAMap.h). Used by ActionCount() and ActionNameAt(). + */ + uint32_t GetActionRule() const; + + virtual AccGroupInfo* GetGroupInfo() const override; + + virtual AccGroupInfo* GetOrCreateGroupInfo() override; + + virtual void ARIAGroupPosition(int32_t* aLevel, int32_t* aSetSize, + int32_t* aPosInSet) const override; + + // Data Members + // mContent can be null in a DocAccessible if the document has no body or + // root element. + nsCOMPtr<nsIContent> mContent; + RefPtr<DocAccessible> mDoc; + + LocalAccessible* mParent; + nsTArray<LocalAccessible*> mChildren; + int32_t mIndexInParent; + + // These are used to determine whether to send cache updates. + Maybe<nsRect> mBounds; + int32_t mFirstLineStart; + + /** + * Maintain a reference to the ComputedStyle of our frame so we can + * send cache updates when style changes are observed. + * + * This RefPtr is initialised in BundleFieldsForCache to the ComputedStyle + * for our initial frame. + * Style changes are observed in one of two ways: + * 1. Style changes on the same frame are observed in + * nsIFrame::DidSetComputedStyle. + * 2. Style changes for reconstructed frames are handled in + * DocAccessible::PruneOrInsertSubtree. + * In both cases, we call into MaybeQueueCacheUpdateForStyleChanges. There, we + * compare a11y-relevant properties in mOldComputedStyle with the current + * ComputedStyle fetched from GetFrame()->Style(). Finally, we send cache + * updates for attributes affected by the style change and update + * mOldComputedStyle to the style of our current frame. + */ + RefPtr<const ComputedStyle> mOldComputedStyle; + + static const uint8_t kStateFlagsBits = 11; + static const uint8_t kContextFlagsBits = 3; + + /** + * Keep in sync with StateFlags, ContextFlags, and AccTypes. + */ + mutable uint32_t mStateFlags : kStateFlagsBits; + uint32_t mContextFlags : kContextFlagsBits; + uint32_t mReorderEventTarget : 1; + uint32_t mShowEventTarget : 1; + uint32_t mHideEventTarget : 1; + + void StaticAsserts() const; + +#ifdef A11Y_LOG + friend void logging::Tree(const char* aTitle, const char* aMsgText, + LocalAccessible* aRoot, + logging::GetTreePrefix aPrefixFunc, + void* aGetTreePrefixData); + friend void logging::TreeSize(const char* aTitle, const char* aMsgText, + LocalAccessible* aRoot); +#endif + friend class DocAccessible; + friend class xpcAccessible; + friend class TreeMutation; + + UniquePtr<mozilla::a11y::EmbeddedObjCollector> mEmbeddedObjCollector; + int32_t mIndexOfEmbeddedChild; + + friend class EmbeddedObjCollector; + + mutable AccGroupInfo* mGroupInfo; + friend class AccGroupInfo; + + private: + LocalAccessible() = delete; + LocalAccessible(const LocalAccessible&) = delete; + LocalAccessible& operator=(const LocalAccessible&) = delete; + + /** + * Traverses the accessible's parent chain in search of an accessible with + * a frame. Returns the frame when found. Includes special handling for + * OOP iframe docs and tab documents. + */ + nsIFrame* FindNearestAccessibleAncestorFrame(); +}; + +NS_DEFINE_STATIC_IID_ACCESSOR(LocalAccessible, NS_ACCESSIBLE_IMPL_IID) + +//////////////////////////////////////////////////////////////////////////////// +// LocalAccessible downcasting method + +inline LocalAccessible* Accessible::AsLocal() { + return IsLocal() ? static_cast<LocalAccessible*>(this) : nullptr; +} + +} // namespace a11y +} // namespace mozilla + +#endif |