Magic-Mirror/gecko-dev
1
0
Fork 0
mirror of https://github.com/mozilla/gecko-dev.git synced 2024-12-11 16:32:59 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity
050beb7609
gecko-dev/accessible/generic/HyperTextAccessible.h

592 lines
19 KiB
C++
Raw Blame History

/* -*- 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 mozilla_a11y_HyperTextAccessible_h__
#define mozilla_a11y_HyperTextAccessible_h__
#include "AccessibleWrap.h"
#include "nsIAccessibleText.h"
#include "nsIAccessibleTypes.h"
#include "nsDirection.h"
#include "WordMovementType.h"
#include "nsIFrame.h"
#include "nsISelectionController.h"
class nsFrameSelection;
class nsRange;
class nsIWidget;
namespace mozilla {
namespace dom {
class Selection;
}
namespace a11y {
class TextRange;
struct DOMPoint {
DOMPoint() : node(nullptr), idx(0) { }
DOMPoint(nsINode* aNode, int32_t aIdx) : node(aNode), idx(aIdx) { }
nsINode* node;
int32_t idx;
};
// This character marks where in the text returned via Text interface,
// that embedded object characters exist
const char16_t kEmbeddedObjectChar = 0xfffc;
const char16_t kImaginaryEmbeddedObjectChar = ' ';
const char16_t kForcedNewLineChar = '\n';
/**
* Special Accessible that knows how contain both text and embedded objects
*/
class HyperTextAccessible : public AccessibleWrap
{
public:
HyperTextAccessible(nsIContent* aContent, DocAccessible* aDoc);
NS_DECL_ISUPPORTS_INHERITED
// Accessible
virtual nsIAtom* LandmarkRole() const override;
virtual int32_t GetLevelInternal() override;
virtual already_AddRefed<nsIPersistentProperties> NativeAttributes() override;
virtual mozilla::a11y::role NativeRole() override;
virtual uint64_t NativeState() override;
virtual void Shutdown() override;
virtual bool RemoveChild(Accessible* aAccessible) override;
virtual bool InsertChildAt(uint32_t aIndex, Accessible* aChild) override;
virtual Relation RelationByType(RelationType aType) override;
// HyperTextAccessible (static helper method)
// Convert content offset to rendered text offset
nsresult ContentToRenderedOffset(nsIFrame *aFrame, int32_t aContentOffset,
uint32_t *aRenderedOffset) const;
// Convert rendered text offset to content offset
nsresult RenderedToContentOffset(nsIFrame *aFrame, uint32_t aRenderedOffset,
int32_t *aContentOffset) const;
//////////////////////////////////////////////////////////////////////////////
// HyperLinkAccessible
/**
* Return link count within this hypertext accessible.
*/
uint32_t LinkCount()
{ return EmbeddedChildCount(); }
/**
* Return link accessible at the given index.
*/
Accessible* LinkAt(uint32_t aIndex)
{
return GetEmbeddedChildAt(aIndex);
}
/**
* Return index for the given link accessible.
*/
int32_t LinkIndexOf(Accessible* aLink)
{
return GetIndexOfEmbeddedChild(aLink);
}
/**
* Return link accessible at the given text offset.
*/
int32_t LinkIndexAtOffset(uint32_t aOffset)
{
Accessible* child = GetChildAtOffset(aOffset);
return child ? LinkIndexOf(child) : -1;
}
//////////////////////////////////////////////////////////////////////////////
// HyperTextAccessible: DOM point to text offset conversions.
/**
* Turn a DOM point (node and offset) into a character offset of this
* hypertext. Will look for closest match when the DOM node does not have
* an accessible object associated with it. Will return an offset for the end
* of the string if the node is not found.
*
* @param aNode [in] the node to look for
* @param aNodeOffset [in] the offset to look for
* if -1 just look directly for the node
* if >=0 and aNode is text, this represents a char offset
* if >=0 and aNode is not text, this represents a child node offset
* @param aIsEndOffset [in] if true, then then this offset is not inclusive. The character
* indicated by the offset returned is at [offset - 1]. This means
* if the passed-in offset is really in a descendant, then the offset returned
* will come just after the relevant embedded object characer.
* If false, then the offset is inclusive. The character indicated
* by the offset returned is at [offset]. If the passed-in offset in inside a
* descendant, then the returned offset will be on the relevant embedded object char.
*/
uint32_t DOMPointToOffset(nsINode* aNode, int32_t aNodeOffset,
bool aIsEndOffset = false) const;
/**
* Transform the given a11y point into the offset relative this hypertext.
*/
uint32_t TransformOffset(Accessible* aDescendant, uint32_t aOffset,
bool aIsEndOffset) const;
/**
* Convert start and end hypertext offsets into DOM range. Note that if
* aStartOffset and/or aEndOffset is in generated content such as ::before or
* ::after, the result range excludes the generated content. See also
* ClosestNotGeneratedDOMPoint() for more information.
*
* @param aStartOffset [in] the given start hypertext offset
* @param aEndOffset [in] the given end hypertext offset
* @param aRange [in, out] the range whose bounds to set
* @return true if conversion was successful
*/
bool OffsetsToDOMRange(int32_t aStartOffset, int32_t aEndOffset,
nsRange* aRange);
/**
* Convert the given offset into DOM point.
*
* If offset is at text leaf then DOM point is (text node, offsetInTextNode),
* if before embedded object then (parent node, indexInParent), if after then
* (parent node, indexInParent + 1).
*/
DOMPoint OffsetToDOMPoint(int32_t aOffset);
/**
* Return true if the used ARIA role (if any) allows the hypertext accessible
* to expose text interfaces.
*/
bool IsTextRole();
//////////////////////////////////////////////////////////////////////////////
// TextAccessible
/**
* Return character count within the hypertext accessible.
*/
uint32_t CharacterCount() const
{ return GetChildOffset(ChildCount()); }
/**
* Get a character at the given offset (don't support magic offsets).
*/
bool CharAt(int32_t aOffset, nsAString& aChar,
int32_t* aStartOffset = nullptr, int32_t* aEndOffset = nullptr)
{
NS_ASSERTION(!aStartOffset == !aEndOffset,
"Offsets should be both defined or both undefined!");
int32_t childIdx = GetChildIndexAtOffset(aOffset);
if (childIdx == -1)
return false;
Accessible* child = GetChildAt(childIdx);
child->AppendTextTo(aChar, aOffset - GetChildOffset(childIdx), 1);
if (aStartOffset && aEndOffset) {
*aStartOffset = aOffset;
*aEndOffset = aOffset + aChar.Length();
}
return true;
}
char16_t CharAt(int32_t aOffset)
{
nsAutoString charAtOffset;
CharAt(aOffset, charAtOffset);
return charAtOffset.CharAt(0);
}
/**
* Return true if char at the given offset equals to given char.
*/
bool IsCharAt(int32_t aOffset, char16_t aChar)
{ return CharAt(aOffset) == aChar; }
/**
* Return true if terminal char is at the given offset.
*/
bool IsLineEndCharAt(int32_t aOffset)
{ return IsCharAt(aOffset, '\n'); }
/**
* Return text between given offsets.
*/
void TextSubstring(int32_t aStartOffset, int32_t aEndOffset, nsAString& aText);
/**
* Return text before/at/after the given offset corresponding to
* the boundary type.
*/
void TextBeforeOffset(int32_t aOffset, AccessibleTextBoundary aBoundaryType,
int32_t* aStartOffset, int32_t* aEndOffset,
nsAString& aText);
void TextAtOffset(int32_t aOffset, AccessibleTextBoundary aBoundaryType,
int32_t* aStartOffset, int32_t* aEndOffset,
nsAString& aText);
void TextAfterOffset(int32_t aOffset, AccessibleTextBoundary aBoundaryType,
int32_t* aStartOffset, int32_t* aEndOffset,
nsAString& aText);
/**
* Return text attributes for the given text range.
*/
already_AddRefed<nsIPersistentProperties>
TextAttributes(bool aIncludeDefAttrs, int32_t aOffset,
int32_t* aStartOffset, int32_t* aEndOffset);
/**
* Return text attributes applied to the accessible.
*/
already_AddRefed<nsIPersistentProperties> DefaultTextAttributes();
/**
* Return text offset of the given child accessible within hypertext
* accessible.
*
* @param aChild [in] accessible child to get text offset for
* @param aInvalidateAfter [in, optional] indicates whether invalidate
* cached offsets for next siblings of the child
*/
int32_t GetChildOffset(const Accessible* aChild,
bool aInvalidateAfter = false) const
{
int32_t index = GetIndexOf(aChild);
return index == -1 ? -1 : GetChildOffset(index, aInvalidateAfter);
}
/**
* Return text offset for the child accessible index.
*/
int32_t GetChildOffset(uint32_t aChildIndex,
bool aInvalidateAfter = false) const;
/**
* Return child accessible at the given text offset.
*
* @param aOffset [in] the given text offset
*/
int32_t GetChildIndexAtOffset(uint32_t aOffset) const;
/**
* Return child accessible at the given text offset.
*
* @param aOffset [in] the given text offset
*/
Accessible* GetChildAtOffset(uint32_t aOffset) const
{
return GetChildAt(GetChildIndexAtOffset(aOffset));
}
/**
* Return true if the given offset/range is valid.
*/
bool IsValidOffset(int32_t aOffset);
bool IsValidRange(int32_t aStartOffset, int32_t aEndOffset);
/**
* Return an offset at the given point.
*/
int32_t OffsetAtPoint(int32_t aX, int32_t aY, uint32_t aCoordType);
/**
* Return a rect of the given text range relative given coordinate system.
*/
nsIntRect TextBounds(int32_t aStartOffset, int32_t aEndOffset,
uint32_t aCoordType = nsIAccessibleCoordinateType::COORDTYPE_SCREEN_RELATIVE);
/**
* Return a rect for character at given offset relative given coordinate
* system.
*/
nsIntRect CharBounds(int32_t aOffset, uint32_t aCoordType)
{
int32_t endOffset = aOffset == static_cast<int32_t>(CharacterCount()) ?
aOffset : aOffset + 1;
return TextBounds(aOffset, endOffset, aCoordType);
}
/**
* Get/set caret offset, if no caret then -1.
*/
int32_t CaretOffset() const;
void SetCaretOffset(int32_t aOffset);
/**
* Provide the line number for the caret.
* @return 1-based index for the line number with the caret
*/
int32_t CaretLineNumber();
/**
* Return the caret rect and the widget containing the caret within this
* text accessible.
*
* @param [out] the widget containing the caret
* @return the caret rect
*/
mozilla::LayoutDeviceIntRect GetCaretRect(nsIWidget** aWidget);
/**
* Return selected regions count within the accessible.
*/
int32_t SelectionCount();
/**
* Return the start and end offset of the specified selection.
*/
bool SelectionBoundsAt(int32_t aSelectionNum,
int32_t* aStartOffset, int32_t* aEndOffset);
/*
* Changes the start and end offset of the specified selection.
* @return true if succeeded
*/
bool SetSelectionBoundsAt(int32_t aSelectionNum,
int32_t aStartOffset, int32_t aEndOffset);
/**
* Adds a selection bounded by the specified offsets.
* @return true if succeeded
*/
bool AddToSelection(int32_t aStartOffset, int32_t aEndOffset);
/*
* Removes the specified selection.
* @return true if succeeded
*/
bool RemoveFromSelection(int32_t aSelectionNum);
/**
* Scroll the given text range into view.
*/
void ScrollSubstringTo(int32_t aStartOffset, int32_t aEndOffset,
uint32_t aScrollType);
/**
* Scroll the given text range to the given point.
*/
void ScrollSubstringToPoint(int32_t aStartOffset,
int32_t aEndOffset,
uint32_t aCoordinateType,
int32_t aX, int32_t aY);
/**
* Return a range that encloses the text control or the document this
* accessible belongs to.
*/
void EnclosingRange(TextRange& aRange) const;
/**
* Return an array of disjoint ranges for selected text within the text control
* or the document this accessible belongs to.
*/
void SelectionRanges(nsTArray<TextRange>* aRanges) const;
/**
* Return an array of disjoint ranges of visible text within the text control
* or the document this accessible belongs to.
*/
void VisibleRanges(nsTArray<TextRange>* aRanges) const;
/**
* Return a range containing the given accessible.
*/
void RangeByChild(Accessible* aChild, TextRange& aRange) const;
/**
* Return a range containing an accessible at the given point.
*/
void RangeAtPoint(int32_t aX, int32_t aY, TextRange& aRange) const;
//////////////////////////////////////////////////////////////////////////////
// EditableTextAccessible
void ReplaceText(const nsAString& aText);
void InsertText(const nsAString& aText, int32_t aPosition);
void CopyText(int32_t aStartPos, int32_t aEndPos);
void CutText(int32_t aStartPos, int32_t aEndPos);
void DeleteText(int32_t aStartPos, int32_t aEndPos);
void PasteText(int32_t aPosition);
/**
* Return the editor associated with the accessible.
*/
virtual already_AddRefed<nsIEditor> GetEditor() const;
/**
* Return DOM selection object for the accessible.
*/
dom::Selection* DOMSelection() const;
protected:
virtual ~HyperTextAccessible() { }
// Accessible
virtual ENameValueFlag NativeName(nsString& aName) override;
// HyperTextAccessible
/**
* Transform magic offset into text offset.
*/
index_t ConvertMagicOffset(int32_t aOffset) const;
/**
* Adjust an offset the caret stays at to get a text by line boundary.
*/
uint32_t AdjustCaretOffset(uint32_t aOffset) const;
/**
* Return true if caret is at end of line.
*/
bool IsCaretAtEndOfLine() const;
/**
* Return true if the given offset points to terminal empty line if any.
*/
bool IsEmptyLastLineOffset(int32_t aOffset)
{
return aOffset == static_cast<int32_t>(CharacterCount()) &&
IsLineEndCharAt(aOffset - 1);
}
/**
* Return an offset of the found word boundary.
*/
uint32_t FindWordBoundary(uint32_t aOffset, nsDirection aDirection,
EWordMovementType aWordMovementType)
{
return FindOffset(aOffset, aDirection, eSelectWord, aWordMovementType);
}
/**
* Used to get begin/end of previous/this/next line. Note: end of line
* is an offset right before '\n' character if any, the offset is right after
* '\n' character is begin of line. In case of wrap word breaks these offsets
* are equal.
*/
enum EWhichLineBoundary {
ePrevLineBegin,
ePrevLineEnd,
eThisLineBegin,
eThisLineEnd,
eNextLineBegin,
eNextLineEnd
};
/**
* Return an offset for requested line boundary. See constants above.
*/
uint32_t FindLineBoundary(uint32_t aOffset,
EWhichLineBoundary aWhichLineBoundary);
/**
* Return an offset corresponding to the given direction and selection amount
* relative the given offset. A helper used to find word or line boundaries.
*/
uint32_t FindOffset(uint32_t aOffset, nsDirection aDirection,
nsSelectionAmount aAmount,
EWordMovementType aWordMovementType = eDefaultBehavior);
/**
* Return the boundaries of the substring in case of textual frame or
* frame boundaries in case of non textual frame, offsets are ignored.
*/
nsIntRect GetBoundsInFrame(nsIFrame* aFrame,
uint32_t aStartRenderedOffset,
uint32_t aEndRenderedOffset);
// Selection helpers
/**
* Return frame selection object for the accessible.
*/
already_AddRefed<nsFrameSelection> FrameSelection() const;
/**
* Return selection ranges within the accessible subtree.
*/
void GetSelectionDOMRanges(int16_t aType, nsTArray<nsRange*>* aRanges);
nsresult SetSelectionRange(int32_t aStartPos, int32_t aEndPos);
/**
* Convert the given DOM point to a DOM point in non-generated contents.
*
* If aDOMPoint is in ::before, the result is immediately after it.
* If aDOMPoint is in ::after, the result is immediately before it.
*
* @param aDOMPoint [in] A DOM node and an index of its child. This may
* be in a generated content such as ::before or
* ::after.
* @param aElementContent [in] An nsIContent representing an element of
* aDOMPoint.node.
* @return An DOM point which must not be in generated
* contents.
*/
DOMPoint ClosestNotGeneratedDOMPoint(const DOMPoint& aDOMPoint,
nsIContent* aElementContent);
// Helpers
nsresult GetDOMPointByFrameOffset(nsIFrame* aFrame, int32_t aOffset,
Accessible* aAccessible,
mozilla::a11y::DOMPoint* aPoint);
/**
* Set 'misspelled' text attribute and return range offsets where the
* attibute is stretched. If the text is not misspelled at the given offset
* then we expose only range offsets where text is not misspelled. The method
* is used by TextAttributes() method.
*
* @param aIncludeDefAttrs [in] points whether text attributes having default
* values of attributes should be included
* @param aSourceNode [in] the node we start to traverse from
* @param aStartOffset [in, out] the start offset
* @param aEndOffset [in, out] the end offset
* @param aAttributes [out, optional] result attributes
*/
void GetSpellTextAttr(nsINode* aNode, int32_t aNodeOffset,
uint32_t* aStartOffset, uint32_t* aEndOffset,
nsIPersistentProperties* aAttributes);
/**
* Set xml-roles attributes for MathML elements.
* @param aAttributes
*/
void SetMathMLXMLRoles(nsIPersistentProperties* aAttributes);
private:
/**
* End text offsets array.
*/
mutable nsTArray<uint32_t> mOffsets;
};
////////////////////////////////////////////////////////////////////////////////
// Accessible downcasting method
inline HyperTextAccessible*
Accessible::AsHyperText()
{
return IsHyperText() ? static_cast<HyperTextAccessible*>(this) : nullptr;
}
} // namespace a11y
} // namespace mozilla
#endif
Reference in New Issue View Git Blame Copy Permalink