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;
// When a section of the document is contentEditable, all tables should be
// treated as data tables, otherwise users may not be able to work with rich
// text editors that allow creating and editing tables.
if (node() && node()->hasEditableStyle())
return true;
// 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);
if (!table->element() || !isHTMLTableElement(table->element()))
return false;
// if there is a caption element, summary, THEAD, or TFOOT section, it's most certainly a data table
HTMLTableElement* tableElement = toHTMLTableElement(table->element());
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;
// if there's a colgroup or col element, it's probably a data table.
for (const auto& child : childrenOfType<Element>(*tableElement)) {
if (child.hasTagName(colTag) || child.hasTagName(colgroupTag))
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
table->recalcSectionsIfNeeded();
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;
// If there are at least 20 rows, we'll call it a data table.
if (numRows >= 20)
return true;
// Store the background color of the table to check against cell's background colors.
const RenderStyle& tableStyle = table->style();
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;
unsigned cellsWithTopBorder = 0;
unsigned cellsWithBottomBorder = 0;
unsigned cellsWithLeftBorder = 0;
unsigned cellsWithRightBorder = 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;
Element* cellElement = cell->element();
if (!cellElement)
continue;
if (cell->width() < 1 || cell->height() < 1)
continue;
validCellCount++;
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->hasTagName(tdTag) || cellElement->hasTagName(thTag)) {
HTMLTableCellElement* tableCellElement = toHTMLTableCellElement(cellElement);
if (!tableCellElement->headers().isEmpty() || !tableCellElement->abbr().isEmpty()
|| !tableCellElement->axis().isEmpty() || !tableCellElement->scope().isEmpty())
return true;
}
const RenderStyle& renderStyle = cell->style();
// If the empty-cells style is set, we'll call it a data table.
if (renderStyle.emptyCells() == HIDE)
return true;
// If a cell has matching bordered sides, call it a (fully) bordered cell.
if ((cell->borderTop() > 0 && cell->borderBottom() > 0)
|| (cell->borderLeft() > 0 && cell->borderRight() > 0))
borderedCellCount++;
// Also keep track of each individual border, so we can catch tables where most
// cells have a bottom border, for example.
if (cell->borderTop() > 0)
cellsWithTopBorder++;
if (cell->borderBottom() > 0)
cellsWithBottomBorder++;
if (cell->borderLeft() > 0)
cellsWithLeftBorder++;
if (cell->borderRight() > 0)
cellsWithRightBorder++;
// If the cell has a different color from the table and there is cell spacing,
// then it is probably a data table cell (spacing and colors take the place of borders).
Color cellColor = renderStyle.visitedDependentColor(CSSPropertyBackgroundColor);
if (table->hBorderSpacing() > 0 && table->vBorderSpacing() > 0
&& tableBGColor != cellColor && cellColor.alpha() != 1)
backgroundDifferenceCellCount++;
// If we've found 10 "good" cells, we don't need to keep searching.
if (borderedCellCount >= 10 || backgroundDifferenceCellCount >= 10)
return true;
// For the first 5 rows, cache the background color so we can check if this table has zebra-striped rows.
if (row < 5 && row == alternatingRowColorCount) {
RenderObject* renderRow = cell->parent();
if (!renderRow || !renderRow->isBoxModelObject() || !toRenderBoxModelObject(renderRow)->isTableRow())
continue;
const RenderStyle& rowRenderStyle = renderRow->style();
Color rowColor = rowRenderStyle.visitedDependentColor(CSSPropertyBackgroundColor);
alternatingRowColors[alternatingRowColorCount] = rowColor;
alternatingRowColorCount++;
}
}
if (!row && headersInFirstRowCount == numCols && numCols > 1)
return true;
}
if (headersInFirstColumnCount == numRows && numRows > 1)
return true;
// if there is less than two valid cells, it's not a data table
if (validCellCount <= 1)
return false;
// half of the cells had borders, it's a data table
unsigned neededCellCount = validCellCount / 2;
if (borderedCellCount >= neededCellCount
|| cellsWithTopBorder >= neededCellCount
|| cellsWithBottomBorder >= neededCellCount
|| cellsWithLeftBorder >= neededCellCount
|| cellsWithRightBorder >= neededCellCount)
return true;
// half had different background colors, it's a data table
if (backgroundDifferenceCellCount >= neededCellCount)
return true;
// Check if there is an alternating row background color indicating a zebra striped style pattern.
if (alternatingRowColorCount > 2) {
Color firstColor = alternatingRowColors[0];
for (int k = 1; k < alternatingRowColorCount; k++) {
// If an odd row was the same color as the first row, its not alternating.
if (k % 2 == 1 && alternatingRowColors[k] == firstColor)
return false;
// If an even row is not the same as the first row, its not alternating.
if (!(k % 2) && alternatingRowColors[k] != firstColor)
return false;
}
return true;
}
return false;
}
CollapsedBorderValue RenderTableCell::collapsedAfterBorder() const
{
RenderTable* table = this->table();
// For after border, we need to check, in order of precedence:
// (1) Our after border.
int before = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderBeforeColor, table->style()->direction(), table->style()->writingMode());
int after = CSSProperty::resolveDirectionAwareProperty(CSSPropertyWebkitBorderAfterColor, table->style()->direction(), table->style()->writingMode());
CollapsedBorderValue result = CollapsedBorderValue(&style()->borderAfter(), style()->visitedDependentColor(after), BCELL);
RenderTableCell* nextCell = table->cellBelow(this);
if (nextCell) {
// (2) An after cell's before border.
result = chooseBorder(result, CollapsedBorderValue(&nextCell->style()->borderBefore(), nextCell->style()->visitedDependentColor(before), BCELL));
if (!result.exists())
return result;
}
// (3) Our row's after border. (FIXME: Deal with rowspan!)
result = chooseBorder(result, CollapsedBorderValue(&parent()->style()->borderAfter(), parent()->style()->visitedDependentColor(after), BROW));
if (!result.exists())
return result;
// (4) The next row's before border.
if (nextCell) {
result = chooseBorder(result, CollapsedBorderValue(&nextCell->parent()->style()->borderBefore(), nextCell->parent()->style()->visitedDependentColor(before), BROW));
if (!result.exists())
return result;
}
// Now check row groups.
RenderTableSection* currSection = section();
if (row() + rowSpan() >= currSection->numRows()) {
// (5) Our row group's after border.
result = chooseBorder(result, CollapsedBorderValue(&currSection->style()->borderAfter(), currSection->style()->visitedDependentColor(after), BROWGROUP));
if (!result.exists())
return result;
// (6) Following row group's before border.
currSection = table->sectionBelow(currSection);
if (currSection) {
result = chooseBorder(result, CollapsedBorderValue(&currSection->style()->borderBefore(), currSection->style()->visitedDependentColor(before), BROWGROUP));
if (!result.exists())
return result;
}
}
if (!currSection) {
// (8) Our column and column group's after borders.
RenderTableCol* colElt = table->colElement(col());
if (colElt) {
result = chooseBorder(result, CollapsedBorderValue(&colElt->style()->borderAfter(), colElt->style()->visitedDependentColor(after), BCOL));
if (!result.exists()) return result;
if (colElt->parent()->isTableCol()) {
result = chooseBorder(result, CollapsedBorderValue(&colElt->parent()->style()->borderAfter(), colElt->parent()->style()->visitedDependentColor(after), BCOLGROUP));
if (!result.exists())
return result;
}
}
// (9) The table's after border.
result = chooseBorder(result, CollapsedBorderValue(&table->style()->borderAfter(), table->style()->visitedDependentColor(after), BTABLE));
if (!result.exists())
return result;
}
return result;
}
void AccessibilityTable::addChildren()
{
if (!isDataTable()) {
AccessibilityRenderObject::addChildren();
return;
}
ASSERT(!m_haveChildren);
m_haveChildren = true;
if (!m_renderer)
return;
RenderTable* table = static_cast<RenderTable*>(m_renderer);
AXObjectCache* axCache = m_renderer->document()->axObjectCache();
// go through all the available sections to pull out the rows
// and add them as children
RenderTableSection* tableSection = table->header();
if (!tableSection)
tableSection = table->firstBody();
if (!tableSection)
return;
RenderTableSection* initialTableSection = tableSection;
while (tableSection) {
HashSet<AccessibilityObject*> appendedRows;
unsigned numRows = tableSection->numRows();
unsigned numCols = tableSection->numColumns();
for (unsigned rowIndex = 0; rowIndex < numRows; ++rowIndex) {
for (unsigned colIndex = 0; colIndex < numCols; ++colIndex) {
RenderTableCell* cell = tableSection->cellAt(rowIndex, colIndex).cell;
if (!cell)
continue;
AccessibilityObject* rowObject = axCache->get(cell->parent());
if (!rowObject->isTableRow())
continue;
AccessibilityTableRow* row = static_cast<AccessibilityTableRow*>(rowObject);
// we need to check every cell for a new row, because cell spans
// can cause us to mess rows if we just check the first column
if (appendedRows.contains(row))
continue;
row->setRowIndex((int)m_rows.size());
m_rows.append(row);
m_children.append(row);
appendedRows.add(row);
}
}
tableSection = table->sectionBelow(tableSection, true);
}
// make the columns based on the number of columns in the first body
unsigned length = initialTableSection->numColumns();
for (unsigned i = 0; i < length; ++i) {
AccessibilityTableColumn* column = static_cast<AccessibilityTableColumn*>(axCache->get(ColumnRole));
column->setColumnIndex((int)i);
column->setParentTable(this);
m_columns.append(column);
m_children.append(column);
}
AccessibilityObject* headerContainerObject = headerContainer();
if (headerContainerObject)
m_children.append(headerContainerObject);
}
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++;
// if the cell has a different color from the table and there is cell spacing,
// then it is probably a data table cell (spacing and colors take the place of borders)
Color cellColor = renderStyle->visitedDependentColor(CSSPropertyBackgroundColor);
if (table->hBorderSpacing() > 0 && table->vBorderSpacing() > 0
&& tableBGColor != cellColor && cellColor.alpha() != 1)
backgroundDifferenceCellCount++;
// if we've found 10 "good" cells, we don't need to keep searching
if (borderedCellCount >= 10 || backgroundDifferenceCellCount >= 10)
return true;
// For the first 5 rows, cache the background color so we can check if this table has zebra-striped rows.
if (row < 5 && row == alternatingRowColorCount) {
RenderObject* renderRow = cell->parent();
if (!renderRow || !renderRow->isBoxModelObject() || !toRenderBoxModelObject(renderRow)->isTableRow())
continue;
RenderStyle* rowRenderStyle = renderRow->style();
if (!rowRenderStyle)
continue;
Color rowColor = rowRenderStyle->visitedDependentColor(CSSPropertyBackgroundColor);
alternatingRowColors[alternatingRowColorCount] = rowColor;
alternatingRowColorCount++;
}
}
if (!row && headersInFirstRowCount == numCols && numCols > 1)
return true;
}
if (headersInFirstColumnCount == numRows && numRows > 1)
return true;
// if there is less than two valid cells, it's not a data table
if (validCellCount <= 1)
return false;
// half of the cells had borders, it's a data table
unsigned neededCellCount = validCellCount / 2;
if (borderedCellCount >= neededCellCount)
return true;
// half had different background colors, it's a data table
if (backgroundDifferenceCellCount >= neededCellCount)
return true;
// Check if there is an alternating row background color indicating a zebra striped style pattern.
if (alternatingRowColorCount > 2) {
Color firstColor = alternatingRowColors[0];
for (int k = 1; k < alternatingRowColorCount; k++) {
// If an odd row was the same color as the first row, its not alternating.
if (k % 2 == 1 && alternatingRowColors[k] == firstColor)
return false;
// If an even row is not the same as the first row, its not alternating.
if (!(k % 2) && alternatingRowColors[k] != firstColor)
return false;
}
return true;
}
return false;
}
void AccessibilityTable::addChildren()
{
if (!isAccessibilityTable()) {
AccessibilityRenderObject::addChildren();
return;
}
ASSERT(!m_haveChildren);
m_haveChildren = true;
if (!m_renderer || !m_renderer->isTable())
return;
RenderTable* table = toRenderTable(m_renderer);
AXObjectCache* axCache = m_renderer->document()->axObjectCache();
// go through all the available sections to pull out the rows
// and add them as children
// 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();
if (!tableSection)
return;
RenderTableSection* initialTableSection = tableSection;
while (tableSection) {
HashSet<AccessibilityObject*> appendedRows;
unsigned numRows = tableSection->numRows();
unsigned numCols = tableSection->numColumns();
for (unsigned rowIndex = 0; rowIndex < numRows; ++rowIndex) {
for (unsigned colIndex = 0; colIndex < numCols; ++colIndex) {
RenderTableCell* cell = tableSection->primaryCellAt(rowIndex, colIndex);
if (!cell)
continue;
AccessibilityObject* rowObject = axCache->getOrCreate(cell->parent());
if (!rowObject->isTableRow())
continue;
AccessibilityTableRow* row = static_cast<AccessibilityTableRow*>(rowObject);
// we need to check every cell for a new row, because cell spans
// can cause us to mess rows if we just check the first column
if (appendedRows.contains(row))
continue;
row->setRowIndex((int)m_rows.size());
m_rows.append(row);
if (!row->accessibilityIsIgnored())
m_children.append(row);
#if PLATFORM(GTK)
else
m_children.append(row->children());
#endif
appendedRows.add(row);
}
}
tableSection = table->sectionBelow(tableSection, SkipEmptySections);
}
// make the columns based on the number of columns in the first body
unsigned length = initialTableSection->numColumns();
for (unsigned i = 0; i < length; ++i) {
AccessibilityTableColumn* column = static_cast<AccessibilityTableColumn*>(axCache->getOrCreate(ColumnRole));
column->setColumnIndex((int)i);
column->setParent(this);
m_columns.append(column);
if (!column->accessibilityIsIgnored())
m_children.append(column);
}
AccessibilityObject* headerContainerObject = headerContainer();
if (headerContainerObject && !headerContainerObject->accessibilityIsIgnored())
m_children.append(headerContainerObject);
}
CollapsedBorderValue RenderTableCell::collapsedBottomBorder() const
{
// For border top, we need to check, in order of precedence:
// (1) Our bottom border.
CollapsedBorderValue result = CollapsedBorderValue(&style()->borderBottom(), BCELL);
RenderTableCell* nextCell = table()->cellBelow(this);
if (nextCell) {
// (2) A following cell's top border.
result = compareBorders(result, CollapsedBorderValue(&nextCell->style()->borderTop(), BCELL));
if (!result.exists())
return result;
}
// (3) Our row's bottom border. (FIXME: Deal with rowspan!)
result = compareBorders(result, CollapsedBorderValue(&parent()->style()->borderBottom(), BROW));
if (!result.exists())
return result;
// (4) The next row's top border.
if (nextCell) {
result = compareBorders(result, CollapsedBorderValue(&nextCell->parent()->style()->borderTop(), BROW));
if (!result.exists())
return result;
}
// Now check row groups.
RenderTableSection* currSection = section();
if (row() + rowSpan() >= currSection->numRows()) {
// (5) Our row group's bottom border.
result = compareBorders(result, CollapsedBorderValue(&currSection->style()->borderBottom(), BROWGROUP));
if (!result.exists())
return result;
// (6) Following row group's top border.
currSection = table()->sectionBelow(currSection);
if (currSection) {
result = compareBorders(result, CollapsedBorderValue(&currSection->style()->borderTop(), BROWGROUP));
if (!result.exists())
return result;
}
}
if (!currSection) {
// (8) Our column and column group's bottom borders.
RenderTableCol* colElt = table()->colElement(col());
if (colElt) {
result = compareBorders(result, CollapsedBorderValue(&colElt->style()->borderBottom(), BCOL));
if (!result.exists()) return result;
if (colElt->parent()->isTableCol()) {
result = compareBorders(result, CollapsedBorderValue(&colElt->parent()->style()->borderBottom(), BCOLGROUP));
if (!result.exists())
return result;
}
}
// (9) The table's bottom border.
result = compareBorders(result, CollapsedBorderValue(&table()->style()->borderBottom(), BTABLE));
if (!result.exists())
return result;
}
return result;
}