C++ VisiblePositionRange类代码示例

static gboolean webkitAccessibleTextSetCaretOffset(AtkText* text, gint offset)
{
    AccessibilityObject* coreObject = core(text);

    if (!coreObject->isAccessibilityRenderObject())
        return FALSE;

    RenderObject* renderer = coreObject->renderer();
    if (renderer && renderer->isListItem()) {
        String markerText = toRenderListItem(renderer)->markerTextWithSuffix();
        int markerLength = markerText.length();
        if (offset < markerLength)
            return FALSE;

        // We need to adjust the offset for list items.
        offset -= markerLength;
    }

    PlainTextRange textRange(offset, 0);
    VisiblePositionRange range = coreObject->visiblePositionRangeForRange(textRange);
    if (range.isNull())
        return FALSE;

    coreObject->setSelectedVisiblePositionRange(range);
    return TRUE;
}

int AccessibilityObject::lengthForVisiblePositionRange(const VisiblePositionRange& visiblePositionRange) const
{
    // FIXME: Multi-byte support
    if (visiblePositionRange.isNull())
        return -1;
    
    int length = 0;
    RefPtr<Range> range = makeRange(visiblePositionRange.start, visiblePositionRange.end);
    for (TextIterator it(range.get()); !it.atEnd(); it.advance()) {
        // non-zero length means textual node, zero length means replaced node (AKA "attachments" in AX)
        if (it.length() != 0) {
            length += it.length();
        } else {
            // locate the node and starting offset for this replaced range
            int exception = 0;
            Node* node = it.range()->startContainer(exception);
            ASSERT(node == it.range()->endContainer(exception));
            int offset = it.range()->startOffset(exception);

            if (replacedNodeNeedsCharacter(node->childNode(offset)))
                length++;
        }
    }
    
    return length;
}

String AccessibilityObject::stringForVisiblePositionRange(const VisiblePositionRange& visiblePositionRange) const
{
    if (visiblePositionRange.isNull())
        return String();

    Vector<UChar> resultVector;
    RefPtr<Range> range = makeRange(visiblePositionRange.start, visiblePositionRange.end);
    for (TextIterator it(range.get()); !it.atEnd(); it.advance()) {
        // non-zero length means textual node, zero length means replaced node (AKA "attachments" in AX)
        if (it.length() != 0) {
            resultVector.append(it.characters(), it.length());
        } else {
            // locate the node and starting offset for this replaced range
            int exception = 0;
            Node* node = it.range()->startContainer(exception);
            ASSERT(node == it.range()->endContainer(exception));
            int offset = it.range()->startOffset(exception);

            if (replacedNodeNeedsCharacter(node->childNode(offset))) {
                resultVector.append(objectReplacementCharacter);
            }
        }
    }

    return String::adopt(resultVector);
}

String AccessibilityObject::stringForVisiblePositionRange(const VisiblePositionRange& visiblePositionRange) const
{
    if (visiblePositionRange.isNull())
        return String();

    StringBuilder builder;
    RefPtr<Range> range = makeRange(visiblePositionRange.start, visiblePositionRange.end);
    for (TextIterator it(range.get()); !it.atEnd(); it.advance()) {
        // non-zero length means textual node, zero length means replaced node (AKA "attachments" in AX)
        if (it.length()) {
            // Add a textual representation for list marker text
            String listMarkerText = listMarkerTextForNodeAndPosition(it.node(), visiblePositionRange.start);
            if (!listMarkerText.isEmpty())
                builder.append(listMarkerText);

            builder.append(it.characters(), it.length());
        } else {
            // locate the node and starting offset for this replaced range
            int exception = 0;
            Node* node = it.range()->startContainer(exception);
            ASSERT(node == it.range()->endContainer(exception));
            int offset = it.range()->startOffset(exception);

            if (replacedNodeNeedsCharacter(node->childNode(offset)))
                builder.append(objectReplacementCharacter);
        }
    }

    return builder.toString();
}

static gboolean webkitAccessibleTextSetSelection(AtkText* text, gint selectionNum, gint startOffset, gint endOffset)
{
    // WebCore does not support multiple selection, so anything but 0 does not make sense for now.
    if (selectionNum)
        return FALSE;

    AccessibilityObject* coreObject = core(text);
    if (!coreObject->isAccessibilityRenderObject())
        return FALSE;

    // Consider -1 and out-of-bound values and correct them to length
    gint textCount = webkitAccessibleTextGetCharacterCount(text);
    if (startOffset < 0 || startOffset > textCount)
        startOffset = textCount;
    if (endOffset < 0 || endOffset > textCount)
        endOffset = textCount;

    // We need to adjust the offsets for the list item marker.
    RenderObject* renderer = coreObject->renderer();
    if (renderer && renderer->isListItem()) {
        String markerText = toRenderListItem(renderer)->markerTextWithSuffix();
        int markerLength = markerText.length();
        if (startOffset < markerLength || endOffset < markerLength)
            return FALSE;

        startOffset -= markerLength;
        endOffset -= markerLength;
    }

    PlainTextRange textRange(startOffset, endOffset - startOffset);
    VisiblePositionRange range = coreObject->visiblePositionRangeForRange(textRange);
    if (range.isNull())
        return FALSE;

    coreObject->setSelectedVisiblePositionRange(range);
    return TRUE;
}