accessibilityobject.cpp

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    VisiblePosition endPosition = endOfLine(nextVisiblePos);

    // as long as the position hasn't reached the end of the doc,  keep searching for a valid line end position
    // There are cases like when the position is next to a floating object that'll return null for end of line. This code will avoid returning null.
    while (endPosition.isNull() && nextVisiblePos.isNotNull()) {
        nextVisiblePos = nextVisiblePos.next();
        endPosition = endOfLine(nextVisiblePos);
    }

    return endPosition;
}

VisiblePosition AccessibilityObject::previousLineStartPosition(const VisiblePosition& visiblePos) const
{
    if (visiblePos.isNull())
        return VisiblePosition();

    // make sure we move off of a line start
    VisiblePosition prevVisiblePos = visiblePos.previous();
    if (prevVisiblePos.isNull())
        return VisiblePosition();

    VisiblePosition startPosition = startOfLine(prevVisiblePos);

    // as long as the position hasn't reached the beginning of the doc,  keep searching for a valid line start position
    // There are cases like when the position is next to a floating object that'll return null for start of line. This code will avoid returning null.
    if (startPosition.isNull()) {
        while (startPosition.isNull() && prevVisiblePos.isNotNull()) {
            prevVisiblePos = prevVisiblePos.previous();
            startPosition = startOfLine(prevVisiblePos);
        }
    } else
        startPosition = updateAXLineStartForVisiblePosition(startPosition);

    return startPosition;
}

VisiblePosition AccessibilityObject::nextSentenceEndPosition(const VisiblePosition& visiblePos) const
{
    // FIXME: FO 2 IMPLEMENT (currently returns incorrect answer)
    // Related? <rdar://problem/3927736> Text selection broken in 8A336
    if (visiblePos.isNull())
        return VisiblePosition();

    // make sure we move off of a sentence end
    VisiblePosition nextVisiblePos = visiblePos.next();
    if (nextVisiblePos.isNull())
        return VisiblePosition();

    // an empty line is considered a sentence. If it's skipped, then the sentence parser will not
    // see this empty line.  Instead, return the end position of the empty line.
    VisiblePosition endPosition;
    
    String lineString = plainText(makeRange(startOfLine(nextVisiblePos), endOfLine(nextVisiblePos)).get());
    if (lineString.isEmpty())
        endPosition = nextVisiblePos;
    else
        endPosition = endOfSentence(nextVisiblePos);

    return endPosition;
}

VisiblePosition AccessibilityObject::previousSentenceStartPosition(const VisiblePosition& visiblePos) const
{
    // FIXME: FO 2 IMPLEMENT (currently returns incorrect answer)
    // Related? <rdar://problem/3927736> Text selection broken in 8A336
    if (visiblePos.isNull())
        return VisiblePosition();

    // make sure we move off of a sentence start
    VisiblePosition previousVisiblePos = visiblePos.previous();
    if (previousVisiblePos.isNull())
        return VisiblePosition();

    // treat empty line as a separate sentence.
    VisiblePosition startPosition;
    
    String lineString = plainText(makeRange(startOfLine(previousVisiblePos), endOfLine(previousVisiblePos)).get());
    if (lineString.isEmpty())
        startPosition = previousVisiblePos;
    else
        startPosition = startOfSentence(previousVisiblePos);

    return startPosition;
}

VisiblePosition AccessibilityObject::nextParagraphEndPosition(const VisiblePosition& visiblePos) const
{
    if (visiblePos.isNull())
        return VisiblePosition();

    // make sure we move off of a paragraph end
    VisiblePosition nextPos = visiblePos.next();
    if (nextPos.isNull())
        return VisiblePosition();

    return endOfParagraph(nextPos);
}

VisiblePosition AccessibilityObject::previousParagraphStartPosition(const VisiblePosition& visiblePos) const
{
    if (visiblePos.isNull())
        return VisiblePosition();

    // make sure we move off of a paragraph start
    VisiblePosition previousPos = visiblePos.previous();
    if (previousPos.isNull())
        return VisiblePosition();

    return startOfParagraph(previousPos);
}

// NOTE: Consider providing this utility method as AX API
VisiblePosition AccessibilityObject::visiblePositionForIndex(unsigned, bool) const
{
    return VisiblePosition();
}

AccessibilityObject* AccessibilityObject::accessibilityObjectForPosition(const VisiblePosition& visiblePos) const
{
    if (visiblePos.isNull())
        return 0;

    RenderObject* obj = visiblePos.deepEquivalent().node()->renderer();
    if (!obj)
        return 0;

    return obj->document()->axObjectCache()->getOrCreate(obj);
}

int AccessibilityObject::lineForPosition(const VisiblePosition& visiblePos) const
{
    if (visiblePos.isNull())
        return 0;

    unsigned lineCount = 0;
    VisiblePosition currentVisiblePos = visiblePos;
    VisiblePosition savedVisiblePos;

    // move up until we get to the top
    // FIXME: This only takes us to the top of the rootEditableElement, not the top of the
    // top document.
    while (currentVisiblePos.isNotNull() && !(inSameLine(currentVisiblePos, savedVisiblePos))) {
        ++lineCount;
        savedVisiblePos = currentVisiblePos;
        VisiblePosition prevVisiblePos = previousLinePosition(currentVisiblePos, 0);
        currentVisiblePos = prevVisiblePos;
    }

    return lineCount - 1;
}

// NOTE: Consider providing this utility method as AX API
PlainTextRange AccessibilityObject::plainTextRangeForVisiblePositionRange(const VisiblePositionRange& positionRange) const
{
    int index1 = index(positionRange.start);
    int index2 = index(positionRange.end);
    if (index1 < 0 || index2 < 0 || index1 > index2)
        return PlainTextRange();

    return PlainTextRange(index1, index2 - index1);
}

// NOTE: Consider providing this utility method as AX API
int AccessibilityObject::index(const VisiblePosition&) const
{
    return -1;
}

// Given a line number, the range of characters of the text associated with this accessibility
// object that contains the line number.
PlainTextRange AccessibilityObject::doAXRangeForLine(unsigned) const
{
    return PlainTextRange();
}

// The composed character range in the text associated with this accessibility object that
// is specified by the given screen coordinates. This parameterized attribute returns the
// complete range of characters (including surrogate pairs of multi-byte glyphs) at the given
// screen coordinates.
// NOTE: This varies from AppKit when the point is below the last line. AppKit returns an
// an error in that case. We return textControl->text().length(), 1. Does this matter?
PlainTextRange AccessibilityObject::doAXRangeForPosition(const IntPoint& point) const
{
    int i = index(visiblePositionForPoint(point));
    if (i < 0)
        return PlainTextRange();

    return PlainTextRange(i, 1);
}

// The composed character range in the text associated with this accessibility object that
// is specified by the given index value. This parameterized attribute returns the complete
// range of characters (including surrogate pairs of multi-byte glyphs) at the given index.
PlainTextRange AccessibilityObject::doAXRangeForIndex(unsigned) const
{
    return PlainTextRange();
}

// Given a character index, the range of text associated with this accessibility object
// over which the style in effect at that character index applies.
PlainTextRange AccessibilityObject::doAXStyleRangeForIndex(unsigned index) const
{
    VisiblePositionRange range = styleRangeForPosition(visiblePositionForIndex(index, false));
    return plainTextRangeForVisiblePositionRange(range);
}

// A substring of the text associated with this accessibility object that is
// specified by the given character range.
String AccessibilityObject::doAXStringForRange(const PlainTextRange&) const
{
    return String();
}

// The bounding rectangle of the text associated with this accessibility object that is
// specified by the given range. This is the bounding rectangle a sighted user would see
// on the display screen, in pixels.
IntRect AccessibilityObject::doAXBoundsForRange(const PlainTextRange&) const
{
    return IntRect();
}

// Given an indexed character, the line number of the text associated with this accessibility
// object that contains the character.
unsigned AccessibilityObject::doAXLineForIndex(unsigned index)
{
    return lineForPosition(visiblePositionForIndex(index, false));
}

FrameView* AccessibilityObject::documentFrameView() const 
{ 
    const AccessibilityObject* object = this;
    while (object && !object->isAccessibilityRenderObject()) 
        object = object->parentObject();
        
    if (!object)
        return 0;

    return object->documentFrameView();
}    

AccessibilityObject* AccessibilityObject::doAccessibilityHitTest(const IntPoint&) const
{
    return 0;
}

AccessibilityObject* AccessibilityObject::focusedUIElement() const
{
    return 0;
}

AccessibilityObject* AccessibilityObject::observableObject() const
{
    return 0;
}

AccessibilityRole AccessibilityObject::roleValue() const
{
    return UnknownRole;
}
    
AccessibilityRole AccessibilityObject::ariaRoleAttribute() const
{
    return UnknownRole;
}

bool AccessibilityObject::isPresentationalChildOfAriaRole() const
{
    return false;
}

bool AccessibilityObject::ariaRoleHasPresentationalChildren() const
{
    return false;
}

void AccessibilityObject::clearChildren()
{
    m_haveChildren = false;
    m_children.clear();
}

void AccessibilityObject::childrenChanged()
{
    return;
}

void AccessibilityObject::addChildren()
{
}

void AccessibilityObject::selectedChildren(AccessibilityChildrenVector&)
{
}

void AccessibilityObject::visibleChildren(AccessibilityChildrenVector&)
{
}
    
unsigned AccessibilityObject::axObjectID() const
{
    return m_id;
}

void AccessibilityObject::setAXObjectID(unsigned axObjectID)
{
    m_id = axObjectID;
}

const String& AccessibilityObject::actionVerb() const
{
    // FIXME: Need to add verbs for select elements.
    DEFINE_STATIC_LOCAL(const String, buttonAction, (AXButtonActionVerb()));
    DEFINE_STATIC_LOCAL(const String, textFieldAction, (AXTextFieldActionVerb()));
    DEFINE_STATIC_LOCAL(const String, radioButtonAction, (AXRadioButtonActionVerb()));
    DEFINE_STATIC_LOCAL(const String, checkedCheckBoxAction, (AXCheckedCheckBoxActionVerb()));
    DEFINE_STATIC_LOCAL(const String, uncheckedCheckBoxAction, (AXUncheckedCheckBoxActionVerb()));
    DEFINE_STATIC_LOCAL(const String, linkAction, (AXLinkActionVerb()));
    DEFINE_STATIC_LOCAL(const String, noAction, ());

    switch (roleValue()) {
        case ButtonRole:
            return buttonAction;
        case TextFieldRole:
        case TextAreaRole:
            return textFieldAction;
        case RadioButtonRole:
            return radioButtonAction;
        case CheckBoxRole:
            return isChecked() ? checkedCheckBoxAction : uncheckedCheckBoxAction;
        case LinkRole:
        case WebCoreLinkRole:
            return linkAction;
        default:
            return noAction;
    }
}

void AccessibilityObject::updateBackingStore()
{
}
    
} // namespace WebCore