gecko-dev/accessible/generic/Accessible.h

1238 lines
33 KiB
C++

/* -*- 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 _Accessible_H_
#define _Accessible_H_
#include "mozilla/a11y/AccTypes.h"
#include "mozilla/a11y/RelationType.h"
#include "mozilla/a11y/Role.h"
#include "mozilla/a11y/States.h"
#include "nsIContent.h"
#include "nsString.h"
#include "nsTArray.h"
#include "nsRefPtrHashtable.h"
struct nsRoleMapEntry;
struct nsRect;
class nsIFrame;
class nsIAtom;
struct nsIntRect;
class nsIPersistentProperties;
class nsView;
namespace mozilla {
namespace a11y {
class Accessible;
class AccEvent;
class AccGroupInfo;
class ApplicationAccessible;
class DocAccessible;
class EmbeddedObjCollector;
class HTMLImageMapAccessible;
class HTMLLIAccessible;
class HyperTextAccessible;
class ImageAccessible;
class KeyBinding;
class ProxyAccessible;
class Relation;
class RootAccessible;
class TableAccessible;
class TableCellAccessible;
class TextLeafAccessible;
class XULLabelAccessible;
class XULTreeAccessible;
/**
* Name type flags.
*/
enum ENameValueFlag {
/**
* Name either
* a) present (not empty): !name.IsEmpty()
* b) no name (was missed): name.IsVoid()
*/
eNameOK,
/**
* Name was left empty by the author on purpose:
* name.IsEmpty() && !name.IsVoid().
*/
eNoNameOnPurpose,
/**
* Name was computed from the subtree.
*/
eNameFromSubtree,
/**
* Tooltip was used as a name.
*/
eNameFromTooltip
};
/**
* Group position (level, position in set and set size).
*/
struct GroupPos
{
GroupPos() : level(0), posInSet(0), setSize(0) { }
int32_t level;
int32_t posInSet;
int32_t setSize;
};
/**
* An index type. Assert if out of range value was attempted to be used.
*/
class index_t
{
public:
MOZ_IMPLICIT index_t(int32_t aVal) : mVal(aVal) {}
operator uint32_t() const
{
MOZ_ASSERT(mVal >= 0, "Attempt to use wrong index!");
return mVal;
}
bool IsValid() const { return mVal >= 0; }
private:
int32_t mVal;
};
typedef nsRefPtrHashtable<nsPtrHashKey<const void>, Accessible>
AccessibleHashtable;
#define NS_ACCESSIBLE_IMPL_IID \
{ /* 133c8bf4-4913-4355-bd50-426bd1d6e1ad */ \
0x133c8bf4, \
0x4913, \
0x4355, \
{ 0xbd, 0x50, 0x42, 0x6b, 0xd1, 0xd6, 0xe1, 0xad } \
}
class Accessible : public nsISupports
{
public:
Accessible(nsIContent* aContent, DocAccessible* aDoc);
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_CLASS(Accessible)
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.
*/
virtual nsIFrame* GetFrame() const;
/**
* Return DOM node associated with the accessible.
*/
virtual nsINode* GetNode() const;
inline already_AddRefed<nsIDOMNode> DOMNode() const
{
nsCOMPtr<nsIDOMNode> DOMNode = do_QueryInterface(GetNode());
return DOMNode.forget();
}
nsIContent* GetContent() const { return mContent; }
/**
* Return node type information of DOM node associated with the accessible.
*/
bool IsContent() const
{ return GetNode() && GetNode()->IsNodeOfType(nsINode::eCONTENT); }
/**
* Return the unique identifier of the accessible.
*/
void* UniqueID() { return static_cast<void*>(this); }
/**
* Return language associated with the accessible.
*/
void Language(nsAString& aLocale);
/**
* Get the description of this accessible.
*/
virtual void Description(nsString& aDescription);
/**
* Get the value of this accessible.
*/
virtual void Value(nsString& aValue);
/**
* Get help string for the accessible.
*/
void Help(nsString& aHelp) const { aHelp.Truncate(); }
/**
* Get the name of this accessible.
*
* Note: aName.IsVoid() when name was left empty by the author on purpose.
* aName.IsEmpty() when the author missed name, AT can try to repair a name.
*/
virtual ENameValueFlag Name(nsString& aName);
/**
* 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).
*/
mozilla::a11y::role Role();
/**
* Return true if ARIA role is specified on the element.
*/
bool HasARIARole() const { return mRoleMapEntry; }
bool IsARIARole(nsIAtom* aARIARole) const;
bool HasStrongARIARole() const;
/**
* Retrun ARIA role map if any.
*/
nsRoleMapEntry* ARIARoleMap() const { return mRoleMapEntry; }
/**
* 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();
/**
* Return all states of accessible (including ARIA states).
*/
virtual uint64_t State();
/**
* 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 if accessible is unavailable.
*/
bool Unavailable() const
{
uint64_t state = NativelyUnavailable() ? states::UNAVAILABLE : 0;
ApplyARIAState(&state);
return state & states::UNAVAILABLE;
}
/**
* Return the states of accessible, not taking into account ARIA states.
* Use State() to get complete set of states.
*/
virtual uint64_t NativeState();
/**
* 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();
/**
* Return true if native unavailable state present.
*/
virtual bool NativelyUnavailable() const;
/**
* Return object attributes for the accessible.
*/
virtual already_AddRefed<nsIPersistentProperties> Attributes();
/**
* Return group position (level, position in set and set size).
*/
virtual mozilla::a11y::GroupPos GroupPosition();
/**
* Used by ChildAtPoint() method to get direct or deepest child at point.
*/
enum EWhichChildAtPoint {
eDirectChild,
eDeepestChild
};
/**
* 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 Accessible* ChildAtPoint(int32_t aX, int32_t aY,
EWhichChildAtPoint aWhichChild);
/**
* Return the focused child if any.
*/
virtual Accessible* FocusedChild();
/**
* Return calculated group level based on accessible hierarchy.
*/
virtual int32_t GetLevelInternal();
/**
* Calculate position in group and group size ('posinset' and 'setsize') based
* on accessible hierarchy.
*
* @param aPosInSet [out] accessible position in the group
* @param aSetSize [out] the group size
*/
virtual void GetPositionAndSizeInternal(int32_t *aPosInSet,
int32_t *aSetSize);
/**
* Get the relation of the given type.
*/
virtual Relation RelationByType(RelationType aType);
//////////////////////////////////////////////////////////////////////////////
// Initializing methods
/**
* Shutdown this accessible object.
*/
virtual void Shutdown();
/**
* Set the ARIA role map entry for a new accessible.
*/
void SetRoleMapEntry(nsRoleMapEntry* aRoleMapEntry)
{ mRoleMapEntry = aRoleMapEntry; }
/**
* Cache children if necessary.
*/
void EnsureChildren();
/**
* Set the child count to -1 (unknown) and null out cached child pointers.
* Should be called when accessible tree is changed because document has
* transformed. Note, if accessible cares about its parent relation chain
* itself should override this method to do nothing.
*/
virtual void InvalidateChildren();
/**
* Append/insert/remove a child. Return true if operation was successful.
*/
bool AppendChild(Accessible* aChild)
{ return InsertChildAt(mChildren.Length(), aChild); }
virtual bool InsertChildAt(uint32_t aIndex, Accessible* aChild);
virtual bool RemoveChild(Accessible* aChild);
//////////////////////////////////////////////////////////////////////////////
// Accessible tree traverse methods
/**
* Return parent accessible.
*/
Accessible* Parent() const { return mParent; }
/**
* Return child accessible at the given index.
*/
virtual Accessible* GetChildAt(uint32_t aIndex) const;
/**
* Return child accessible count.
*/
virtual uint32_t ChildCount() const;
/**
* Return index of the given child accessible.
*/
int32_t GetIndexOf(const Accessible* aChild) const
{ return (aChild->mParent != this) ? -1 : aChild->IndexInParent(); }
/**
* Return index in parent accessible.
*/
virtual int32_t IndexInParent() const;
/**
* Return true if accessible has children;
*/
bool HasChildren() { return !!GetChildAt(0); }
/**
* Return first/last/next/previous sibling of the accessible.
*/
inline Accessible* NextSibling() const
{ return GetSiblingAtOffset(1); }
inline Accessible* PrevSibling() const
{ return GetSiblingAtOffset(-1); }
inline Accessible* FirstChild()
{ return GetChildAt(0); }
inline Accessible* LastChild()
{
uint32_t childCount = ChildCount();
return childCount != 0 ? GetChildAt(childCount - 1) : nullptr;
}
/**
* Return embedded accessible children count.
*/
uint32_t EmbeddedChildCount();
/**
* Return embedded accessible child at the given index.
*/
Accessible* GetEmbeddedChildAt(uint32_t aIndex);
/**
* Return index of the given embedded accessible child.
*/
int32_t GetIndexOfEmbeddedChild(Accessible* aChild);
/**
* 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(); }
Accessible* ContentChildAt(uint32_t aIndex) const
{ return mChildren.ElementAt(aIndex); }
/**
* Return true if children were initialized.
*/
inline bool AreChildrenCached() const
{ return !IsChildrenFlag(eChildrenUninitialized); }
/**
* 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 this accessible allows accessible children from anonymous subtree.
*/
virtual bool CanHaveAnonChildren();
/**
* Return true if the accessible is an acceptable child.
*/
virtual bool IsAcceptableChild(Accessible* aPossibleChild) const { return true; }
/**
* Returns text of accessible if accessible has text role otherwise empty
* string.
*
* @param aText [in] returned text of the accessible
* @param aStartOffset [in, optional] start offset inside of the accessible,
* if missed entire text is appended
* @param aLength [in, optional] required length of text, if missed
* then text form start offset till the end is appended
*/
virtual void AppendTextTo(nsAString& aText, uint32_t aStartOffset = 0,
uint32_t aLength = UINT32_MAX);
/**
* Assert if child not in parent's cache if the cache was initialized at this
* point.
*/
void TestChildCache(Accessible* aCachedChild) const;
/**
* Return boundaries in screen coordinates.
*/
virtual nsIntRect Bounds() const;
/**
* Return boundaries rect relative the bounding frame.
*/
virtual nsRect RelativeBounds(nsIFrame** aRelativeFrame) const;
/**
* Selects the accessible within its container if applicable.
*/
virtual void SetSelected(bool aSelect);
/**
* Extend selection to this accessible.
*/
void ExtendSelection() { };
/**
* Select the accessible within its container.
*/
void TakeSelection();
/**
* Focus the accessible.
*/
virtual void TakeFocus();
/**
* Scroll the accessible into view.
*/
void ScrollTo(uint32_t aHow) const;
/**
* 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);
//////////////////////////////////////////////////////////////////////////////
// Downcasting and types
inline bool IsAbbreviation() const
{
return mContent->IsHTML() &&
(mContent->Tag() == nsGkAtoms::abbr || mContent->Tag() == nsGkAtoms::acronym);
}
bool IsApplication() const { return mType == eApplicationType; }
ApplicationAccessible* AsApplication();
bool IsAutoComplete() const { return HasGenericType(eAutoComplete); }
bool IsAutoCompletePopup() const
{ return HasGenericType(eAutoCompletePopup); }
bool IsButton() const { return HasGenericType(eButton); }
bool IsCombobox() const { return HasGenericType(eCombobox); }
bool IsDoc() const { return HasGenericType(eDocument); }
DocAccessible* AsDoc();
bool IsGenericHyperText() const { return mType == eHyperTextType; }
bool IsHyperText() const { return HasGenericType(eHyperText); }
HyperTextAccessible* AsHyperText();
bool IsHTMLBr() const { return mType == eHTMLBRType; }
bool IsHTMLCombobox() const { return mType == eHTMLComboboxType; }
bool IsHTMLFileInput() const { return mType == eHTMLFileInputType; }
bool IsHTMLListItem() const { return mType == eHTMLLiType; }
HTMLLIAccessible* AsHTMLListItem();
bool IsHTMLOptGroup() const { return mType == eHTMLOptGroupType; }
bool IsHTMLTable() const { return mType == eHTMLTableType; }
bool IsHTMLTableRow() const { return mType == eHTMLTableRowType; }
bool IsImage() const { return mType == eImageType; }
ImageAccessible* AsImage();
bool IsImageMap() const { return mType == eImageMapType; }
HTMLImageMapAccessible* AsImageMap();
bool IsList() const { return HasGenericType(eList); }
bool IsListControl() const { return HasGenericType(eListControl); }
bool IsMenuButton() const { return HasGenericType(eMenuButton); }
bool IsMenuPopup() const { return mType == eMenuPopupType; }
bool IsProxy() const { return mType == eProxyType; }
ProxyAccessible* Proxy() const
{
MOZ_ASSERT(IsProxy());
return mBits.proxy;
}
bool IsProgress() const { return mType == eProgressType; }
bool IsRoot() const { return mType == eRootType; }
a11y::RootAccessible* AsRoot();
bool IsSelect() const { return HasGenericType(eSelect); }
bool IsTable() const { return HasGenericType(eTable); }
virtual TableAccessible* AsTable() { return nullptr; }
bool IsTableCell() const { return HasGenericType(eTableCell); }
virtual TableCellAccessible* AsTableCell() { return nullptr; }
const TableCellAccessible* AsTableCell() const
{ return const_cast<Accessible*>(this)->AsTableCell(); }
bool IsTableRow() const { return HasGenericType(eTableRow); }
bool IsTextField() const { return mType == eHTMLTextFieldType; }
bool IsTextLeaf() const { return mType == eTextLeafType; }
TextLeafAccessible* AsTextLeaf();
bool IsXULLabel() const { return mType == eXULLabelType; }
XULLabelAccessible* AsXULLabel();
bool IsXULListItem() const { return mType == eXULListItemType; }
bool IsXULTabpanels() const { return mType == eXULTabpanelsType; }
bool IsXULTree() const { return mType == eXULTreeType; }
XULTreeAccessible* AsXULTree();
/**
* Return true if the accessible belongs to the given accessible type.
*/
bool HasGenericType(AccGenericType aType) const;
//////////////////////////////////////////////////////////////////////////////
// ActionAccessible
/**
* Return the number of actions that can be performed on this accessible.
*/
virtual uint8_t ActionCount();
/**
* Return action name at given index.
*/
virtual void ActionNameAt(uint8_t aIndex, nsAString& aName);
/**
* Default to localized action name.
*/
void ActionDescriptionAt(uint8_t aIndex, nsAString& aDescription)
{
nsAutoString name;
ActionNameAt(aIndex, name);
TranslateString(name, aDescription);
}
/**
* Invoke the accessible action.
*/
virtual bool DoAction(uint8_t aIndex);
/**
* Return access key, such as Alt+D.
*/
virtual KeyBinding AccessKey() const;
/**
* 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();
/**
* Return the start offset of the link within the parent accessible.
*/
virtual uint32_t StartOffset();
/**
* Return the end offset of the link within the parent accessible.
*/
virtual uint32_t EndOffset();
/**
* Return true if the link is valid (e. g. points to a valid URL).
*/
inline bool IsLinkValid()
{
NS_PRECONDITION(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 Accessible* AnchorAt(uint32_t aAnchorIndex);
/**
* Returns an anchor URI at the given index.
*/
virtual already_AddRefed<nsIURI> AnchorURIAt(uint32_t aAnchorIndex);
//////////////////////////////////////////////////////////////////////////////
// SelectAccessible
/**
* Return an array of selected items.
*/
virtual void SelectedItems(nsTArray<Accessible*>* aItems);
/**
* Return the number of selected items.
*/
virtual uint32_t SelectedItemCount();
/**
* Return selected item at the given index.
*/
virtual Accessible* GetSelectedItem(uint32_t aIndex);
/**
* Determine if item at the given index is selected.
*/
virtual bool IsItemSelected(uint32_t aIndex);
/**
* Add item at the given index the selection. Return true if success.
*/
virtual bool AddItemToSelection(uint32_t aIndex);
/**
* Remove item at the given index from the selection. Return if success.
*/
virtual bool RemoveItemFromSelection(uint32_t aIndex);
/**
* Select all items. Return true if success.
*/
virtual bool SelectAll();
/**
* Unselect all items. Return true if success.
*/
virtual bool UnselectAll();
//////////////////////////////////////////////////////////////////////////////
// Value (numeric value interface)
virtual double MaxValue() const;
virtual double MinValue() const;
virtual double CurValue() const;
virtual double Step() const;
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 Accessible* CurrentItem();
/**
* Set the current item of the widget.
*/
virtual void SetCurrentItem(Accessible* aItem);
/**
* Return container widget this accessible belongs to.
*/
virtual Accessible* ContainerWidget() const;
/**
* Return the localized string for the given key.
*/
static void TranslateString(const nsString& aKey, nsAString& aStringOut);
/**
* Return true if the accessible is defunct.
*/
bool IsDefunct() const { return mStateFlags & eIsDefunct; }
/**
* Return true 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's group info needs to be updated.
*/
inline bool HasDirtyGroupInfo() const { return mStateFlags & eGroupInfoDirty; }
/**
* Return true if the accessible has associated DOM content.
*/
bool HasOwnContent() const
{ return mContent && !(mStateFlags & eSharedNode); }
/**
* Return true if the accessible has a numeric value.
*/
bool HasNumericValue() const;
/**
* Return true if the accessible state change is processed by handling proper
* DOM UI event, if otherwise then false. For example, HTMLCheckboxAccessible
* process nsIDocumentObserver::ContentStateChanged instead
* 'CheckboxStateChange' event.
*/
bool NeedsDOMUIEvent() const
{ return !(mStateFlags & eIgnoreDOMUIEvent); }
/**
* Get/set survivingInUpdate bit on child indicating that parent recollects
* its children.
*/
bool IsSurvivingInUpdate() const { return mStateFlags & eSurvivingInUpdate; }
void SetSurvivingInUpdate(bool aIsSurviving)
{
if (aIsSurviving)
mStateFlags |= eSurvivingInUpdate;
else
mStateFlags &= ~eSurvivingInUpdate;
}
/**
* Return true if this accessible has a parent whose name depends on this
* accessible.
*/
bool HasNameDependentParent() const
{ return mContextFlags & eHasNameDependentParent; }
/**
* Return true if aria-hidden="true" is applied to the accessible or inherited
* from the parent.
*/
bool IsARIAHidden() const { return mContextFlags & eARIAHidden; }
void SetARIAHidden(bool aIsDefined);
protected:
virtual ~Accessible();
/**
* 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);
/**
* Return object attributes provided by native markup. It doesn't take into
* account ARIA.
*/
virtual already_AddRefed<nsIPersistentProperties> NativeAttributes();
//////////////////////////////////////////////////////////////////////////////
// Initializing, cache and tree traverse methods
/**
* Destroy the object.
*/
void LastRelease();
/**
* Cache accessible children.
*/
virtual void CacheChildren();
/**
* Set accessible parent and index in parent.
*/
virtual void BindToParent(Accessible* aParent, uint32_t aIndexInParent);
virtual void UnbindFromParent();
/**
* Return sibling accessible at the given offset.
*/
virtual Accessible* GetSiblingAtOffset(int32_t aOffset,
nsresult *aError = nullptr) const;
/**
* Flags used to describe the state and type of children.
*/
enum ChildrenFlags {
eChildrenUninitialized = 0, // children aren't initialized
eMixedChildren = 1 << 0, // text leaf children are presented
eEmbeddedChildren = 1 << 1, // all children are embedded objects
eLastChildrenFlag = eEmbeddedChildren
};
/**
* Return true if the children flag is set.
*/
bool IsChildrenFlag(ChildrenFlags aFlag) const
{ return static_cast<ChildrenFlags>(mChildrenFlags) == aFlag; }
/**
* Set children flag.
*/
void SetChildrenFlag(ChildrenFlags aFlag) { mChildrenFlags = aFlag; }
/**
* Flags used to describe the state of this accessible.
* @note keep these flags in sync with ChildrenFlags
*/
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
eHasNumericValue = 1 << 4, // accessible has a numeric value
eGroupInfoDirty = 1 << 5, // accessible needs to update group info
eSubtreeMutating = 1 << 6, // subtree is being mutated
eIgnoreDOMUIEvent = 1 << 7, // don't process DOM UI events for a11y events
eSurvivingInUpdate = 1 << 8, // parent drops children to recollect them
eLastStateFlag = eSurvivingInUpdate
};
/**
* Flags used for contextual information about the accessible.
*/
enum ContextFlags {
eHasNameDependentParent = 1 << 0, // Parent's name depends on this accessible.
eARIAHidden = 1 << 1,
eLastContextFlag = eARIAHidden
};
protected:
//////////////////////////////////////////////////////////////////////////////
// Miscellaneous helpers
/**
* Return ARIA role (helper method).
*/
mozilla::a11y::role ARIATransformRole(mozilla::a11y::role aRole);
//////////////////////////////////////////////////////////////////////////////
// Name helpers
/**
* Returns the accessible name specified by ARIA.
*/
void ARIAName(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);
/**
* Dispatch click event.
*/
virtual void DispatchClickEvent(nsIContent *aContent, uint32_t aActionIndex);
//////////////////////////////////////////////////////////////////////////////
// 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(nsIAtom* aARIAAttr) const;
/**
* Return the action rule based on ARIA enum constants EActionRule
* (see ARIAMap.h). Used by ActionCount() and ActionNameAt().
*/
uint32_t GetActionRule() const;
/**
* Return group info.
*/
AccGroupInfo* GetGroupInfo();
/**
* Set dirty state of the accessible's group info.
*/
inline void SetDirtyGroupInfo(bool aIsDirty)
{
if (aIsDirty)
mStateFlags |= eGroupInfoDirty;
else
mStateFlags &= ~eGroupInfoDirty;
}
/**
* Flag all children group info as needing to be updated.
*/
void InvalidateChildrenGroupInfo();
// Data Members
nsCOMPtr<nsIContent> mContent;
DocAccessible* mDoc;
nsRefPtr<Accessible> mParent;
nsTArray<nsRefPtr<Accessible> > mChildren;
int32_t mIndexInParent;
static const uint8_t kChildrenFlagsBits = 2;
static const uint8_t kStateFlagsBits = 9;
static const uint8_t kContextFlagsBits = 2;
static const uint8_t kTypeBits = 6;
static const uint8_t kGenericTypesBits = 13;
/**
* Keep in sync with ChildrenFlags, StateFlags, ContextFlags, and AccTypes.
*/
uint32_t mChildrenFlags : kChildrenFlagsBits;
uint32_t mStateFlags : kStateFlagsBits;
uint32_t mContextFlags : kContextFlagsBits;
uint32_t mType : kTypeBits;
uint32_t mGenericTypes : kGenericTypesBits;
void StaticAsserts() const;
void AssertInMutatingSubtree() const;
friend class DocAccessible;
friend class xpcAccessible;
friend class AutoTreeMutation;
nsAutoPtr<mozilla::a11y::EmbeddedObjCollector> mEmbeddedObjCollector;
int32_t mIndexOfEmbeddedChild;
friend class EmbeddedObjCollector;
union
{
AccGroupInfo* groupInfo;
ProxyAccessible* proxy;
} mBits;
friend class AccGroupInfo;
/**
* Non-null indicates author-supplied role; possibly state & value as well
*/
nsRoleMapEntry* mRoleMapEntry;
private:
Accessible() = delete;
Accessible(const Accessible&) = delete;
Accessible& operator =(const Accessible&) = delete;
};
NS_DEFINE_STATIC_IID_ACCESSOR(Accessible,
NS_ACCESSIBLE_IMPL_IID)
/**
* Represent key binding associated with accessible (such as access key and
* global keyboard shortcuts).
*/
class KeyBinding
{
public:
/**
* Modifier mask values.
*/
static const uint32_t kShift = 1;
static const uint32_t kControl = 2;
static const uint32_t kAlt = 4;
static const uint32_t kMeta = 8;
static const uint32_t kOS = 16;
static uint32_t AccelModifier();
KeyBinding() : mKey(0), mModifierMask(0) {}
KeyBinding(uint32_t aKey, uint32_t aModifierMask) :
mKey(aKey), mModifierMask(aModifierMask) {}
inline bool IsEmpty() const { return !mKey; }
inline uint32_t Key() const { return mKey; }
inline uint32_t ModifierMask() const { return mModifierMask; }
enum Format {
ePlatformFormat,
eAtkFormat
};
/**
* Return formatted string for this key binding depending on the given format.
*/
inline void ToString(nsAString& aValue,
Format aFormat = ePlatformFormat) const
{
aValue.Truncate();
AppendToString(aValue, aFormat);
}
inline void AppendToString(nsAString& aValue,
Format aFormat = ePlatformFormat) const
{
if (mKey) {
if (aFormat == ePlatformFormat)
ToPlatformFormat(aValue);
else
ToAtkFormat(aValue);
}
}
private:
void ToPlatformFormat(nsAString& aValue) const;
void ToAtkFormat(nsAString& aValue) const;
uint32_t mKey;
uint32_t mModifierMask;
};
/**
* This class makes sure required tasks are done before and after tree
* mutations. Currently this only includes group info invalidation. You must
* have an object of this class on the stack when calling methods that mutate
* the accessible tree.
*/
class AutoTreeMutation
{
public:
explicit AutoTreeMutation(Accessible* aRoot, bool aInvalidationRequired = true) :
mInvalidationRequired(aInvalidationRequired), mRoot(aRoot)
{
MOZ_ASSERT(!(mRoot->mStateFlags & Accessible::eSubtreeMutating));
mRoot->mStateFlags |= Accessible::eSubtreeMutating;
}
~AutoTreeMutation()
{
if (mInvalidationRequired)
mRoot->InvalidateChildrenGroupInfo();
MOZ_ASSERT(mRoot->mStateFlags & Accessible::eSubtreeMutating);
mRoot->mStateFlags &= ~Accessible::eSubtreeMutating;
}
bool mInvalidationRequired;
private:
Accessible* mRoot;
};
} // namespace a11y
} // namespace mozilla
#endif