gecko-dev/accessible/base/nsAccUtils.h

255 lines
7.9 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 nsAccUtils_h_
#define nsAccUtils_h_
#include "mozilla/a11y/Accessible.h"
#include "nsAccessibilityService.h"
#include "nsCoreUtils.h"
#include "nsIDocShell.h"
#include "nsPoint.h"
namespace mozilla {
namespace dom {
class Element;
}
namespace a11y {
class HyperTextAccessible;
class DocAccessible;
class nsAccUtils
{
public:
/**
* Returns value of attribute from the given attributes container.
*
* @param aAttributes - attributes container
* @param aAttrName - the name of requested attribute
* @param aAttrValue - value of attribute
*/
static void GetAccAttr(nsIPersistentProperties *aAttributes,
nsIAtom *aAttrName,
nsAString& aAttrValue);
/**
* Set value of attribute for the given attributes container.
*
* @param aAttributes - attributes container
* @param aAttrName - the name of requested attribute
* @param aAttrValue - new value of attribute
*/
static void SetAccAttr(nsIPersistentProperties *aAttributes,
nsIAtom *aAttrName,
const nsAString& aAttrValue);
static void SetAccAttr(nsIPersistentProperties *aAttributes,
nsIAtom* aAttrName,
nsIAtom* aAttrValue);
/**
* Set group attributes ('level', 'setsize', 'posinset').
*/
static void SetAccGroupAttrs(nsIPersistentProperties *aAttributes,
int32_t aLevel, int32_t aSetSize,
int32_t aPosInSet);
/**
* Get default value of the level for the given accessible.
*/
static int32_t GetDefaultLevel(Accessible* aAcc);
/**
* Return ARIA level value or the default one if ARIA is missed for the
* given accessible.
*/
static int32_t GetARIAOrDefaultLevel(Accessible* aAccessible);
/**
* 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
* @param aTopContent node to end at
*/
static void SetLiveContainerAttributes(nsIPersistentProperties *aAttributes,
nsIContent *aStartContent,
nsIContent *aTopContent);
/**
* 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, nsIAtom *aAtom);
/**
* Return atomic value of ARIA attribute of boolean or NMTOKEN type.
*/
static nsIAtom* GetARIAToken(mozilla::dom::Element* aElement, nsIAtom* aAttr);
/**
* Return document accessible for the given DOM node.
*/
static DocAccessible* GetDocAccessibleFor(nsINode* aNode)
{
nsIPresShell *presShell = nsCoreUtils::GetPresShellFor(aNode);
return GetAccService()->GetDocAccessible(presShell);
}
/**
* 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 Accessible* GetSelectableContainer(Accessible* aAccessible,
uint64_t aState);
/**
* Return a text container accessible for the given node.
*/
static HyperTextAccessible* GetTextContainer(nsINode* aNode);
static Accessible* TableFor(Accessible* aRow);
/**
* Return true if the DOM node of given accessible has aria-selected="true"
* attribute.
*/
static bool IsARIASelected(Accessible* aAccessible);
/**
* Converts the given coordinates to coordinates relative screen.
*
* @param aX [in] the given x coord
* @param aY [in] the given y coord
* @param aCoordinateType [in] specifies coordinates origin (refer to
* nsIAccessibleCoordinateType)
* @param aAccessible [in] the accessible if coordinates are given
* relative it.
* @return converted coordinates
*/
static nsIntPoint ConvertToScreenCoords(int32_t aX, int32_t aY,
uint32_t aCoordinateType,
Accessible* aAccessible);
/**
* Converts the given coordinates relative screen to another coordinate
* system.
*
* @param aX [in, out] the given x coord
* @param aY [in, out] the given y coord
* @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,
Accessible* aAccessible);
/**
* Returns coordinates relative screen for the parent of the given accessible.
*
* @param [in] aAccessible the accessible
*/
static nsIntPoint GetScreenCoordsForParent(Accessible* 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(Accessible* aAccessible);
#endif
/**
* Return text length of the given accessible, return 0 on failure.
*/
static uint32_t TextLength(Accessible* aAccessible);
/**
* Return true if the given accessible is embedded object.
*/
static bool IsEmbeddedObject(Accessible* aAcc)
{
uint32_t role = aAcc->Role();
return role != roles::TEXT_LEAF &&
role != roles::WHITESPACE &&
role != roles::STATICTEXT;
}
/**
* 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 aState | extraState;
}
/**
* 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);
};
} // namespace a11y
} // namespace mozilla
#endif