gecko-dev/accessible/base/TextRange.h

272 lines
7.6 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* 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_TextRange_h__
#define mozilla_a11y_TextRange_h__
#include "mozilla/Move.h"
#include "nsAutoPtr.h"
#include "nsCaseTreatment.h"
#include "nsRect.h"
#include "nsTArray.h"
class nsIVariant;
namespace mozilla {
namespace a11y {
class Accessible;
class HyperTextAccessible;
/**
* A text point (hyper text + offset), represents a boundary of text range.
*/
struct TextPoint final
{
TextPoint(HyperTextAccessible* aContainer, int32_t aOffset) :
mContainer(aContainer), mOffset(aOffset) { }
TextPoint(const TextPoint& aPoint) :
mContainer(aPoint.mContainer), mOffset(aPoint.mOffset) { }
HyperTextAccessible* mContainer;
int32_t mOffset;
bool operator ==(const TextPoint& aPoint) const
{ return mContainer == aPoint.mContainer && mOffset == aPoint.mOffset; }
bool operator <(const TextPoint& aPoint) const;
};
/**
* Represents a text range within the text control or document.
*/
class TextRange final
{
public:
TextRange(HyperTextAccessible* aRoot,
HyperTextAccessible* aStartContainer, int32_t aStartOffset,
HyperTextAccessible* aEndContainer, int32_t aEndOffset);
TextRange() {}
TextRange(TextRange&& aRange) :
mRoot(mozilla::Move(aRange.mRoot)),
mStartContainer(mozilla::Move(aRange.mStartContainer)),
mEndContainer(mozilla::Move(aRange.mEndContainer)),
mStartOffset(aRange.mStartOffset), mEndOffset(aRange.mEndOffset) {}
TextRange& operator= (TextRange&& aRange)
{
mRoot = mozilla::Move(aRange.mRoot);
mStartContainer = mozilla::Move(aRange.mStartContainer);
mEndContainer = mozilla::Move(aRange.mEndContainer);
mStartOffset = aRange.mStartOffset;
mEndOffset = aRange.mEndOffset;
return *this;
}
HyperTextAccessible* StartContainer() const { return mStartContainer; }
int32_t StartOffset() const { return mStartOffset; }
HyperTextAccessible* EndContainer() const { return mEndContainer; }
int32_t EndOffset() const { return mEndOffset; }
bool operator ==(const TextRange& aRange) const
{
return mStartContainer == aRange.mStartContainer &&
mStartOffset == aRange.mStartOffset &&
mEndContainer == aRange.mEndContainer && mEndOffset == aRange.mEndOffset;
}
TextPoint StartPoint() const { return TextPoint(mStartContainer, mStartOffset); }
TextPoint EndPoint() const { return TextPoint(mEndContainer, mEndOffset); }
/**
* Return a container containing both start and end points.
*/
Accessible* Container() const;
/**
* Return a list of embedded objects enclosed by the text range (includes
* partially overlapped objects).
*/
void EmbeddedChildren(nsTArray<Accessible*>* aChildren) const;
/**
* Return text enclosed by the range.
*/
void Text(nsAString& aText) const;
/**
* Return list of bounding rects of the text range by lines.
*/
void Bounds(nsTArray<nsIntRect> aRects) const;
enum ETextUnit {
eFormat,
eWord,
eLine,
eParagraph,
ePage,
eDocument
};
/**
* Move the range or its points on specified amount of given units.
*/
void Move(ETextUnit aUnit, int32_t aCount)
{
MoveEnd(aUnit, aCount);
MoveStart(aUnit, aCount);
}
void MoveStart(ETextUnit aUnit, int32_t aCount)
{
MoveInternal(aUnit, aCount, *mStartContainer, mStartOffset,
mEndContainer, mEndOffset);
}
void MoveEnd(ETextUnit aUnit, int32_t aCount)
{ MoveInternal(aUnit, aCount, *mEndContainer, mEndOffset); }
/**
* Move the range points to the closest unit boundaries.
*/
void Normalize(ETextUnit aUnit);
/**
* Crops the range if it overlaps the given accessible element boundaries,
* returns true if the range was cropped successfully.
*/
bool Crop(Accessible* aContainer);
enum EDirection {
eBackward,
eForward
};
/**
* Return range enclosing the found text.
*/
void FindText(const nsAString& aText, EDirection aDirection,
nsCaseTreatment aCaseSensitive, TextRange* aFoundRange) const;
enum EAttr {
eAnimationStyleAttr,
eAnnotationObjectsAttr,
eAnnotationTypesAttr,
eBackgroundColorAttr,
eBulletStyleAttr,
eCapStyleAttr,
eCaretBidiModeAttr,
eCaretPositionAttr,
eCultureAttr,
eFontNameAttr,
eFontSizeAttr,
eFontWeightAttr,
eForegroundColorAttr,
eHorizontalTextAlignmentAttr,
eIndentationFirstLineAttr,
eIndentationLeadingAttr,
eIndentationTrailingAttr,
eIsActiveAttr,
eIsHiddenAttr,
eIsItalicAttr,
eIsReadOnlyAttr,
eIsSubscriptAttr,
eIsSuperscriptAttr,
eLinkAttr,
eMarginBottomAttr,
eMarginLeadingAttr,
eMarginTopAttr,
eMarginTrailingAttr,
eOutlineStylesAttr,
eOverlineColorAttr,
eOverlineStyleAttr,
eSelectionActiveEndAttr,
eStrikethroughColorAttr,
eStrikethroughStyleAttr,
eStyleIdAttr,
eStyleNameAttr,
eTabsAttr,
eTextFlowDirectionsAttr,
eUnderlineColorAttr,
eUnderlineStyleAttr
};
/**
* Return range enclosing text having requested attribute.
*/
void FindAttr(EAttr aAttr, nsIVariant* aValue, EDirection aDirection,
TextRange* aFoundRange) const;
/**
* Add/remove the text range from selection.
*/
void AddToSelection() const;
void RemoveFromSelection() const;
void Select() const;
/**
* Scroll the text range into view.
*/
enum EHowToAlign {
eAlignToTop,
eAlignToBottom
};
void ScrollIntoView(EHowToAlign aHow) const;
/**
* Return true if this TextRange object represents an actual range of text.
*/
bool IsValid() const { return mRoot; }
void SetStartPoint(HyperTextAccessible* aContainer, int32_t aOffset)
{ mStartContainer = aContainer; mStartOffset = aOffset; }
void SetEndPoint(HyperTextAccessible* aContainer, int32_t aOffset)
{ mStartContainer = aContainer; mStartOffset = aOffset; }
private:
TextRange(const TextRange& aRange) = delete;
TextRange& operator=(const TextRange& aRange) = delete;
friend class HyperTextAccessible;
friend class xpcAccessibleTextRange;
void Set(HyperTextAccessible* aRoot,
HyperTextAccessible* aStartContainer, int32_t aStartOffset,
HyperTextAccessible* aEndContainer, int32_t aEndOffset);
/**
* Text() method helper.
* @param aText [in,out] calculated text
* @param aCurrent [in] currently traversed node
* @param aStartIntlOffset [in] start offset if current node is a text node
* @return true if calculation is not finished yet
*/
bool TextInternal(nsAString& aText, Accessible* aCurrent,
uint32_t aStartIntlOffset) const;
void MoveInternal(ETextUnit aUnit, int32_t aCount,
HyperTextAccessible& aContainer, int32_t aOffset,
HyperTextAccessible* aStopContainer = nullptr,
int32_t aStopOffset = 0);
/**
* A helper method returning a common parent for two given accessible
* elements.
*/
Accessible* CommonParent(Accessible* aAcc1, Accessible* aAcc2,
nsTArray<Accessible*>* aParents1, uint32_t* aPos1,
nsTArray<Accessible*>* aParents2, uint32_t* aPos2) const;
RefPtr<HyperTextAccessible> mRoot;
RefPtr<HyperTextAccessible> mStartContainer;
RefPtr<HyperTextAccessible> mEndContainer;
int32_t mStartOffset;
int32_t mEndOffset;
};
} // namespace a11y
} // namespace mozilla
#endif