gecko-dev/accessible/base/nsAccUtils.h

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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 nsAccUtils_h_
#define nsAccUtils_h_
#include "mozilla/a11y/LocalAccessible.h"
#include "mozilla/a11y/DocManager.h"
#include "nsAccessibilityService.h"
#include "nsCoreUtils.h"
#include "nsIDocShell.h"
#include "nsPoint.h"
namespace mozilla {
class PresShell;
namespace dom {
class Element;
}
namespace a11y {
class HyperTextAccessible;
class DocAccessible;
class Attribute;
class nsAccUtils {
public:
/**
* Set group attributes ('level', 'setsize', 'posinset').
*/
static void SetAccGroupAttrs(AccAttributes* aAttributes, int32_t aLevel,
int32_t aSetSize, int32_t aPosInSet);
/**
* Compute group level for nsIDOMXULContainerItemElement node.
*/
static int32_t GetLevelForXULContainerItem(nsIContent* aContent);
/**
* Set container-foo live region attributes for the given node.
*
* @param aAttributes where to store the attributes
* @param aStartContent node to start from
*/
static void SetLiveContainerAttributes(AccAttributes* aAttributes,
nsIContent* aStartContent);
/**
* Any ARIA property of type boolean or NMTOKEN is undefined if the ARIA
* property is not present, or is "" or "undefined". Do not call
* this method for properties of type string, decimal, IDREF or IDREFS.
*
* Return true if the ARIA property is defined, otherwise false
*/
static bool HasDefinedARIAToken(nsIContent* aContent, nsAtom* aAtom);
/**
* Return atomic value of ARIA attribute of boolean or NMTOKEN type.
*/
static nsStaticAtom* GetARIAToken(mozilla::dom::Element* aElement,
nsAtom* aAttr);
/**
* If the given ARIA attribute has a specific known token value, return it.
* If the specification demands for a fallback value for unknown attribute
* values, return that. For all others, return a nullptr.
*/
static nsStaticAtom* NormalizeARIAToken(mozilla::dom::Element* aElement,
nsAtom* aAttr);
/**
* Return document accessible for the given DOM node.
*/
static DocAccessible* GetDocAccessibleFor(nsINode* aNode) {
return GetAccService()->GetDocAccessible(
nsCoreUtils::GetPresShellFor(aNode));
}
/**
* Return document accessible for the given docshell.
*/
static DocAccessible* GetDocAccessibleFor(nsIDocShellTreeItem* aContainer) {
nsCOMPtr<nsIDocShell> docShell(do_QueryInterface(aContainer));
return GetAccService()->GetDocAccessible(docShell->GetPresShell());
}
/**
* Return single or multi selectable container for the given item.
*
* @param aAccessible [in] the item accessible
* @param aState [in] the state of the item accessible
*/
static LocalAccessible* GetSelectableContainer(LocalAccessible* aAccessible,
uint64_t aState);
/**
* Return a text container accessible for the given node.
*/
static HyperTextAccessible* GetTextContainer(nsINode* aNode);
static LocalAccessible* TableFor(LocalAccessible* aRow);
/**
* Return true if the DOM node of a given accessible has a given attribute
* with a value of "true".
*/
static bool IsDOMAttrTrue(const LocalAccessible* aAccessible, nsAtom* aAttr);
/**
* Return true if the DOM node of given accessible has aria-selected="true"
* attribute.
*/
static inline bool IsARIASelected(const LocalAccessible* aAccessible) {
return IsDOMAttrTrue(aAccessible, nsGkAtoms::aria_selected);
}
/**
* Return true if the DOM node of given accessible has
* aria-multiselectable="true" attribute.
*/
static inline bool IsARIAMultiSelectable(const LocalAccessible* aAccessible) {
return IsDOMAttrTrue(aAccessible, nsGkAtoms::aria_multiselectable);
}
/**
* Converts the given coordinates to coordinates relative screen.
*
* @param aX [in] the given x coord in dev pixels
* @param aY [in] the given y coord in dev pixels
* @param aCoordinateType [in] specifies coordinates origin (refer to
* nsIAccessibleCoordinateType)
* @param aAccessible [in] the accessible if coordinates are given
* relative it.
* @return converted coordinates
*/
static LayoutDeviceIntPoint ConvertToScreenCoords(
int32_t aX, int32_t aY, uint32_t aCoordinateType,
LocalAccessible* aAccessible);
/**
* Converts the given coordinates relative screen to another coordinate
* system.
*
* @param aX [in, out] the given x coord in dev pixels
* @param aY [in, out] the given y coord in dev pixels
* @param aCoordinateType [in] specifies coordinates origin (refer to
* nsIAccessibleCoordinateType)
* @param aAccessible [in] the accessible if coordinates are given
* relative it
*/
static void ConvertScreenCoordsTo(int32_t* aX, int32_t* aY,
uint32_t aCoordinateType,
LocalAccessible* aAccessible);
/**
* Returns screen-relative coordinates (in dev pixels) for the parent of the
* given accessible.
*
* @param [in] aAccessible the accessible
*/
static LayoutDeviceIntPoint GetScreenCoordsForParent(
LocalAccessible* aAccessible);
/**
* Get the 'live' or 'container-live' object attribute value from the given
* ELiveAttrRule constant.
*
* @param aRule [in] rule constant (see ELiveAttrRule in nsAccMap.h)
* @param aValue [out] object attribute value
*
* @return true if object attribute should be exposed
*/
static bool GetLiveAttrValue(uint32_t aRule, nsAString& aValue);
#ifdef DEBUG
/**
* Detect whether the given accessible object implements nsIAccessibleText,
* when it is text or has text child node.
*/
static bool IsTextInterfaceSupportCorrect(LocalAccessible* aAccessible);
#endif
/**
* Return text length of the given accessible, return 0 on failure.
*/
static uint32_t TextLength(Accessible* aAccessible);
/**
* Transform nsIAccessibleStates constants to internal state constant.
*/
static inline uint64_t To64State(uint32_t aState1, uint32_t aState2) {
return static_cast<uint64_t>(aState1) +
(static_cast<uint64_t>(aState2) << 31);
}
/**
* Transform internal state constant to nsIAccessibleStates constants.
*/
static inline void To32States(uint64_t aState64, uint32_t* aState1,
uint32_t* aState2) {
*aState1 = aState64 & 0x7fffffff;
if (aState2) *aState2 = static_cast<uint32_t>(aState64 >> 31);
}
static uint32_t To32States(uint64_t aState, bool* aIsExtra) {
uint32_t extraState = aState >> 31;
*aIsExtra = !!extraState;
return extraState ? extraState : aState;
}
/**
* Return true if the given accessible can't have children. Used when exposing
* to platform accessibility APIs, should the children be pruned off?
*/
static bool MustPrune(Accessible* aAccessible);
/**
* Return true if the given accessible is within an ARIA live region; i.e.
* the container-live attribute would be something other than "off" or empty.
*/
static bool IsARIALive(const LocalAccessible* aAccessible);
};
} // namespace a11y
} // namespace mozilla
#endif