C++ RenderTableSection类代码示例

void AccessibilityTableCell::rowIndexRange(std::pair<unsigned, unsigned>& rowRange)
{
    if (!m_renderer || !m_renderer->isTableCell())
        return;
    
    RenderTableCell* renderCell = toRenderTableCell(m_renderer);
    rowRange.first = renderCell->rowIndex();
    rowRange.second = renderCell->rowSpan();
    
    // since our table might have multiple sections, we have to offset our row appropriately
    RenderTableSection* section = renderCell->section();
    RenderTable* table = renderCell->table();
    if (!table || !section)
        return;

    RenderTableSection* footerSection = table->footer();
    unsigned rowOffset = 0;
    for (RenderTableSection* tableSection = table->topSection(); tableSection; tableSection = table->sectionBelow(tableSection, SkipEmptySections)) {
        // Don't add row offsets for bottom sections that are placed in before the body section.
        if (tableSection == footerSection)
            continue;
        if (tableSection == section)
            break;
        rowOffset += tableSection->numRows();
    }

    rowRange.first += rowOffset;
}

void AccessibilityTableCell::rowIndexRange(pair<int, int>& rowRange)
{
    if (!m_renderer)
        return;
    
    RenderTableCell* renderCell = static_cast<RenderTableCell*>(m_renderer);
    rowRange.first = renderCell->row();
    rowRange.second = renderCell->rowSpan();
    
    // since our table might have multiple sections, we have to offset our row appropriately
    RenderTableSection* section = renderCell->section();
    RenderTable* table = renderCell->table();
    if (!table || !section)
        return;
    
    RenderTableSection* tableSection = table->header();
    if (!tableSection)
        tableSection = table->firstBody();
    
    unsigned rowOffset = 0;
    while (tableSection) {
        if (tableSection == section)
            break;
        rowOffset += tableSection->numRows();
        tableSection = table->sectionBelow(tableSection, true); 
    }

    rowRange.first += rowOffset;
}

AccessibilityObject* AccessibilityTableCell::titleUIElement() const
{
    // Try to find if the first cell in this row is a <th>. If it is,
    // then it can act as the title ui element. (This is only in the
    // case when the table is not appearing as an AXTable.)
    if (!m_renderer || isTableCell())
        return 0;
    
    RenderTableCell* renderCell = static_cast<RenderTableCell*>(m_renderer);

    // If this cell is in the first column, there is no need to continue.
    int col = renderCell->col();
    if (!col)
        return 0;

    int row = renderCell->row();

    RenderTableSection* section = renderCell->section();
    if (!section)
        return 0;
    
    RenderTableCell* headerCell = section->cellAt(row, 0).cell;
    if (!headerCell || headerCell == renderCell)
        return 0;

    Node* cellElement = headerCell->element();
    if (!cellElement || !cellElement->hasTagName(thTag))
        return 0;
    
    return axObjectCache()->get(headerCell);
}

void AccessibilityTableCell::rowIndexRange(pair<int, int>& rowRange)
{
    if (!m_renderer || !m_renderer->isTableCell())
        return;
    
    RenderTableCell* renderCell = toRenderTableCell(m_renderer);
    rowRange.first = renderCell->rowIndex();
    rowRange.second = renderCell->rowSpan();
    
    // since our table might have multiple sections, we have to offset our row appropriately
    RenderTableSection* section = renderCell->section();
    RenderTable* table = renderCell->table();
    if (!table || !section)
        return;

    // FIXME: This will skip a table with just a tfoot. Should fix by using RenderTable::topSection.
    RenderTableSection* tableSection = table->header();
    if (!tableSection)
        tableSection = table->firstBody();
    
    unsigned rowOffset = 0;
    while (tableSection) {
        if (tableSection == section)
            break;
        rowOffset += tableSection->numRows();
        tableSection = table->sectionBelow(tableSection, SkipEmptySections);
    }

    rowRange.first += rowOffset;
}

void AccessibilityTableCell::rowIndexRange(std::pair<unsigned, unsigned>& rowRange)
{
    if (!m_renderer || !m_renderer->isTableCell())
        return;
    
    RenderTableCell* renderCell = toRenderTableCell(m_renderer);
    rowRange.first = renderCell->rowIndex();
    rowRange.second = renderCell->rowSpan();
    
    // since our table might have multiple sections, we have to offset our row appropriately
    RenderTableSection* section = renderCell->section();
    RenderTable* table = renderCell->table();
    if (!table || !section)
        return;

    RenderTableSection* tableSection = table->topSection();    
    unsigned rowOffset = 0;
    while (tableSection) {
        if (tableSection == section)
            break;
        rowOffset += tableSection->numRows();
        tableSection = table->sectionBelow(tableSection, SkipEmptySections);
    }

    rowRange.first += rowOffset;
}

void RenderTableRow::destroy()
{
    RenderTableSection *s = section();
    if (s)
        s->setNeedCellRecalc();
    
    RenderContainer::destroy();
}

void RenderTableCell::willBeDestroyed()
{
    RenderTableSection* recalcSection = parent() ? section() : 0;

    RenderBlock::willBeDestroyed();

    if (recalcSection)
        recalcSection->setNeedsCellRecalc();
}

void RenderTableRow::destroy()
{
    RenderTableSection* recalcSection = section();
    
    RenderContainer::destroy();
    
    if (recalcSection)
        recalcSection->setNeedsCellRecalc();
}

HTMLTableElement* AccessibilityTable::tableElement() const
{
    if (!m_renderer->isTable())
        return nullptr;
    
    RenderTable* table = toRenderTable(m_renderer);
    if (table->element() && isHTMLTableElement(table->element()))
        return toHTMLTableElement(table->element());
    
    // If the table has a display:table-row-group, then the RenderTable does not have a pointer to it's HTMLTableElement.
    // We can instead find it by asking the firstSection for its parent.
    RenderTableSection* firstBody = table->firstBody();
    if (!firstBody || !firstBody->element())
        return nullptr;
    
    Element* actualTable = firstBody->element()->parentElement();
    if (!actualTable || !isHTMLTableElement(actualTable))
        return nullptr;
    
    return toHTMLTableElement(actualTable);
}

HTMLTableElement* AccessibilityTable::tableElement() const
{
    if (!is<RenderTable>(*m_renderer))
        return nullptr;
    
    RenderTable& table = downcast<RenderTable>(*m_renderer);
    if (is<HTMLTableElement>(table.element()))
        return downcast<HTMLTableElement>(table.element());
    
    // If the table has a display:table-row-group, then the RenderTable does not have a pointer to it's HTMLTableElement.
    // We can instead find it by asking the firstSection for its parent.
    RenderTableSection* firstBody = table.firstBody();
    if (!firstBody || !firstBody->element())
        return nullptr;
    
    Element* actualTable = firstBody->element()->parentElement();
    if (!is<HTMLTableElement>(actualTable))
        return nullptr;
    
    return downcast<HTMLTableElement>(actualTable);
}

AccessibilityObject* AccessibilityTableColumn::headerObject()
{
    if (!m_parent)
        return nullptr;
    
    RenderObject* renderer = m_parent->renderer();
    if (!renderer)
        return nullptr;
    if (!is<AccessibilityTable>(*m_parent))
        return nullptr;

    auto& parentTable = downcast<AccessibilityTable>(*m_parent);
    if (!parentTable.isExposableThroughAccessibility())
        return nullptr;
    
    if (parentTable.isAriaTable()) {
        for (const auto& cell : children()) {
            if (cell->ariaRoleAttribute() == ColumnHeaderRole)
                return cell.get();
        }
        
        return nullptr;
    }

    if (!is<RenderTable>(*renderer))
        return nullptr;
    
    RenderTable& table = downcast<RenderTable>(*renderer);

    // try the <thead> section first. this doesn't require th tags
    if (auto* headerObject = headerObjectForSection(table.header(), false))
        return headerObject;
    
    RenderTableSection* bodySection = table.firstBody();
    while (bodySection && bodySection->isAnonymous())
        bodySection = table.sectionBelow(bodySection, SkipEmptySections);
    
    // now try for <th> tags in the first body. If the first body is 
    return headerObjectForSection(bodySection, true);
}

AccessibilityObject* AccessibilityTableCell::titleUIElement() const
{
    // Try to find if the first cell in this row is a <th>. If it is,
    // then it can act as the title ui element. (This is only in the
    // case when the table is not appearing as an AXTable.)
    if (isTableCell() || !m_renderer || !m_renderer->isTableCell())
        return 0;

    // Table cells that are th cannot have title ui elements, since by definition
    // they are title ui elements
    Node* node = m_renderer->node();
    if (node && node->hasTagName(thTag))
        return 0;
    
    RenderTableCell* renderCell = toRenderTableCell(m_renderer);

    // If this cell is in the first column, there is no need to continue.
    int col = renderCell->col();
    if (!col)
        return 0;

    int row = renderCell->rowIndex();

    RenderTableSection* section = renderCell->section();
    if (!section)
        return 0;
    
    RenderTableCell* headerCell = section->primaryCellAt(row, 0);
    if (!headerCell || headerCell == renderCell)
        return 0;

    Node* cellElement = headerCell->node();
    if (!cellElement || !cellElement->hasTagName(thTag))
        return 0;
    
    return axObjectCache()->getOrCreate(headerCell);
}

bool AccessibilityTable::isDataTable() const
{
    if (!m_renderer)
        return false;

    // Do not consider it a data table is it has an ARIA role.
    if (hasARIARole())
        return false;

    // This employs a heuristic to determine if this table should appear.
    // Only "data" tables should be exposed as tables.
    // Unfortunately, there is no good way to determine the difference
    // between a "layout" table and a "data" table.
    
    RenderTable* table = toRenderTable(m_renderer);
    Node* tableNode = table->node();
    if (!tableNode || !tableNode->hasTagName(tableTag))
        return false;

    // if there is a caption element, summary, THEAD, or TFOOT section, it's most certainly a data table
    HTMLTableElement* tableElement = static_cast<HTMLTableElement*>(tableNode);
    if (!tableElement->summary().isEmpty() || tableElement->tHead() || tableElement->tFoot() || tableElement->caption())
        return true;
    
    // if someone used "rules" attribute than the table should appear
    if (!tableElement->rules().isEmpty())
        return true;    
    
    // go through the cell's and check for tell-tale signs of "data" table status
    // cells have borders, or use attributes like headers, abbr, scope or axis
    RenderTableSection* firstBody = table->firstBody();
    if (!firstBody)
        return false;
    
    int numCols = firstBody->numColumns();
    int numRows = firstBody->numRows();
    
    // if there's only one cell, it's not a good AXTable candidate
    if (numRows == 1 && numCols == 1)
        return false;
    
    // store the background color of the table to check against cell's background colors
    RenderStyle* tableStyle = table->style();
    if (!tableStyle)
        return false;
    Color tableBGColor = tableStyle->visitedDependentColor(CSSPropertyBackgroundColor);
    
    // check enough of the cells to find if the table matches our criteria
    // Criteria: 
    //   1) must have at least one valid cell (and)
    //   2) at least half of cells have borders (or)
    //   3) at least half of cells have different bg colors than the table, and there is cell spacing
    unsigned validCellCount = 0;
    unsigned borderedCellCount = 0;
    unsigned backgroundDifferenceCellCount = 0;
    
    Color alternatingRowColors[5];
    int alternatingRowColorCount = 0;
    
    int headersInFirstColumnCount = 0;
    for (int row = 0; row < numRows; ++row) {
    
        int headersInFirstRowCount = 0;
        for (int col = 0; col < numCols; ++col) {    
            RenderTableCell* cell = firstBody->primaryCellAt(row, col);
            if (!cell)
                continue;
            Node* cellNode = cell->node();
            if (!cellNode)
                continue;
            
            if (cell->width() < 1 || cell->height() < 1)
                continue;
            
            validCellCount++;
            
            HTMLTableCellElement* cellElement = static_cast<HTMLTableCellElement*>(cellNode);
            
            bool isTHCell = cellElement->hasTagName(thTag);
            // If the first row is comprised of all <th> tags, assume it is a data table.
            if (!row && isTHCell)
                headersInFirstRowCount++;

            // If the first column is comprised of all <th> tags, assume it is a data table.
            if (!col && isTHCell)
                headersInFirstColumnCount++;
            
            // in this case, the developer explicitly assigned a "data" table attribute
            if (!cellElement->headers().isEmpty() || !cellElement->abbr().isEmpty()
                || !cellElement->axis().isEmpty() || !cellElement->scope().isEmpty())
                return true;
            
            RenderStyle* renderStyle = cell->style();
            if (!renderStyle)
                continue;

            // a cell needs to have matching bordered sides, before it can be considered a bordered cell.
            if ((cell->borderTop() > 0 && cell->borderBottom() > 0)
                || (cell->borderLeft() > 0 && cell->borderRight() > 0))
                borderedCellCount++;
//.........这里部分代码省略.........

int FixedTableLayout::calcWidthArray(int tableWidth)
{
    int usedWidth = 0;

    // iterate over all <col> elements
    RenderObject* child = m_table->firstChild();
    int cCol = 0;
    int nEffCols = m_table->numEffCols();
    m_width.resize(nEffCols);
    m_width.fill(Length(Auto));

    Length grpWidth;
    while (child) {
        if (child->isTableCol()) {
            RenderTableCol *col = static_cast<RenderTableCol *>(child);
            int span = col->span();
            if (col->firstChild())
                grpWidth = col->style()->width();
            else {
                Length w = col->style()->width();
                if (w.isAuto())
                    w = grpWidth;
                int effWidth = 0;
                if (w.isFixed() && w.value() > 0)
                    effWidth = w.value();
                
                int usedSpan = 0;
                int i = 0;
                while (usedSpan < span) {
                    if(cCol + i >= nEffCols) {
                        m_table->appendColumn(span - usedSpan);
                        nEffCols++;
                        m_width.resize(nEffCols);
                        m_width[nEffCols-1] = Length();
                    }
                    int eSpan = m_table->spanOfEffCol(cCol+i);
                    if ((w.isFixed() || w.isPercent()) && w.isPositive()) {
                        m_width[cCol + i].setRawValue(w.type(), w.rawValue() * eSpan);
                        usedWidth += effWidth * eSpan;
                    }
                    usedSpan += eSpan;
                    i++;
                }
                cCol += i;
            }
        } else
            break;

        RenderObject *next = child->firstChild();
        if (!next)
            next = child->nextSibling();
        if (!next && child->parent()->isTableCol()) {
            next = child->parent()->nextSibling();
            grpWidth = Length();
        }
        child = next;
    }

    // Iterate over the first row in case some are unspecified.
    RenderTableSection* section = m_table->header();
    if (!section)
        section = m_table->firstBody();
    if (!section)
        section = m_table->footer();
    if (section && !section->numRows())
        section = m_table->sectionBelow(section, true);
    if (section) {
        cCol = 0;
        RenderObject* firstRow = section->firstChild();
        child = firstRow->firstChild();
        while (child) {
            if (child->isTableCell()) {
                RenderTableCell* cell = static_cast<RenderTableCell*>(child);
                if (cell->prefWidthsDirty())
                    cell->calcPrefWidths();

                Length w = cell->styleOrColWidth();
                int span = cell->colSpan();
                int effWidth = 0;
                if (w.isFixed() && w.isPositive())
                    effWidth = w.value();
                
                int usedSpan = 0;
                int i = 0;
                while (usedSpan < span) {
                    ASSERT(cCol + i < nEffCols);
                    int eSpan = m_table->spanOfEffCol(cCol + i);
                    // Only set if no col element has already set it.
                    if (m_width[cCol + i].isAuto() && w.type() != Auto) {
                        m_width[cCol + i].setRawValue(w.type(), w.rawValue() * eSpan / span);
                        usedWidth += effWidth * eSpan / span;
                    }
                    usedSpan += eSpan;
                    i++;
                }
                cCol += i;
            }
            child = child->nextSibling();
        }
    }
//.........这里部分代码省略.........

int FixedTableLayout::calcWidthArray(int)
{
    int usedWidth = 0;

    // iterate over all <col> elements
    RenderObject* child = m_table->firstChild();
    int nEffCols = m_table->numEffCols();
    m_width.resize(nEffCols);
    m_width.fill(Length(Auto));

    int currentEffectiveColumn = 0;
    Length grpWidth;
    while (child && child->isTableCol()) {
        RenderTableCol* col = toRenderTableCol(child);
        if (col->firstChild())
            grpWidth = col->style()->logicalWidth();
        else {
            Length w = col->style()->logicalWidth();
            if (w.isAuto())
                w = grpWidth;
            int effWidth = 0;
            if (w.isFixed() && w.value() > 0)
                effWidth = w.value();

            int span = col->span();
            while (span) {
                int spanInCurrentEffectiveColumn;
                if (currentEffectiveColumn >= nEffCols) {
                    m_table->appendColumn(span);
                    nEffCols++;
                    m_width.append(Length());
                    spanInCurrentEffectiveColumn = span;
                } else {
                    if (span < m_table->spanOfEffCol(currentEffectiveColumn)) {
                        m_table->splitColumn(currentEffectiveColumn, span);
                        nEffCols++;
                        m_width.append(Length());
                    }
                    spanInCurrentEffectiveColumn = m_table->spanOfEffCol(currentEffectiveColumn);
                }
                if ((w.isFixed() || w.isPercent()) && w.isPositive()) {
                    m_width[currentEffectiveColumn] = w;
                    m_width[currentEffectiveColumn] *= spanInCurrentEffectiveColumn;
                    usedWidth += effWidth * spanInCurrentEffectiveColumn;
                }
                span -= spanInCurrentEffectiveColumn;
                currentEffectiveColumn++;
            }
        }
        col->computePreferredLogicalWidths();

        RenderObject* next = child->firstChild();
        if (!next)
            next = child->nextSibling();
        if (!next && child->parent()->isTableCol()) {
            next = child->parent()->nextSibling();
            grpWidth = Length();
        }
        child = next;
    }

    // Iterate over the first row in case some are unspecified.
    RenderTableSection* section = m_table->topNonEmptySection();
    if (section) {
        int cCol = 0;
        RenderObject* firstRow = section->firstChild();
        child = firstRow->firstChild();
        while (child) {
            if (child->isTableCell()) {
                RenderTableCell* cell = toRenderTableCell(child);
                if (cell->preferredLogicalWidthsDirty())
                    cell->computePreferredLogicalWidths();

                Length w = cell->styleOrColLogicalWidth();
                int span = cell->colSpan();
                int effWidth = 0;
                if (w.isFixed() && w.isPositive())
                    effWidth = w.value();

                int usedSpan = 0;
                int i = 0;
                while (usedSpan < span && cCol + i < nEffCols) {
                    float eSpan = m_table->spanOfEffCol(cCol + i);
                    // Only set if no col element has already set it.
                    if (m_width[cCol + i].isAuto() && w.type() != Auto) {
                        m_width[cCol + i] = w;
                        m_width[cCol + i] *= eSpan / span;
                        usedWidth += effWidth * eSpan / span;
                    }
                    usedSpan += eSpan;
                    i++;
                }
                cCol += i;
            }
            child = child->nextSibling();
        }
    }

    return usedWidth;
}