gecko-dev/accessible/generic/TableAccessible.h

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* 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 TABLE_ACCESSIBLE_H
#define TABLE_ACCESSIBLE_H

#include "nsString.h"
#include "nsTArray.h"

namespace mozilla {
namespace a11y {

class Accessible;

/**
 * Accessible table interface.
 */
class TableAccessible {
 public:
  /**
   * Return the caption accessible if any for this table.
   */
  virtual Accessible* Caption() const { return nullptr; }

  /**
   * Get the summary for this table.
   */
  virtual void Summary(nsString& aSummary) { aSummary.Truncate(); }

  /**
   * Return the number of columns in the table.
   */
  virtual uint32_t ColCount() const { return 0; }

  /**
   * Return the number of rows in the table.
   */
  virtual uint32_t RowCount() { return 0; }

  /**
   * Return the accessible for the cell at the given row and column indices.
   */
  virtual Accessible* CellAt(uint32_t aRowIdx, uint32_t aColIdx) {
    return nullptr;
  }

  /**
   * Return the index of the cell at the given row and column.
   */
  virtual int32_t CellIndexAt(uint32_t aRowIdx, uint32_t aColIdx) {
    return ColCount() * aRowIdx + aColIdx;
  }

  /**
   * Return the column index of the cell with the given index.
   * This returns -1 if the column count is 0 or an invalid index is being
   * passed in.
   */
  virtual int32_t ColIndexAt(uint32_t aCellIdx);

  /**
   * Return the row index of the cell with the given index.
   * This returns -1 if the column count is 0 or an invalid index is being
   * passed in.
   */
  virtual int32_t RowIndexAt(uint32_t aCellIdx);

  /**
   * Get the row and column indices for the cell at the given index.
   * This returns -1 for both output parameters if the column count is 0 or an
   * invalid index is being passed in.
   */
  virtual void RowAndColIndicesAt(uint32_t aCellIdx, int32_t* aRowIdx,
                                  int32_t* aColIdx);

  /**
   * Return the number of columns occupied by the cell at the given row and
   * column indices.
   */
  virtual uint32_t ColExtentAt(uint32_t aRowIdx, uint32_t aColIdx) { return 1; }

  /**
   * Return the number of rows occupied by the cell at the given row and column
   * indices.
   */
  virtual uint32_t RowExtentAt(uint32_t aRowIdx, uint32_t aColIdx) { return 1; }

  /**
   * Get the description of the given column.
   */
  virtual void ColDescription(uint32_t aColIdx, nsString& aDescription) {
    aDescription.Truncate();
  }

  /**
   * Get the description for the given row.
   */
  virtual void RowDescription(uint32_t aRowIdx, nsString& aDescription) {
    aDescription.Truncate();
  }

  /**
   * Return true if the given column is selected.
   */
  virtual bool IsColSelected(uint32_t aColIdx) { return false; }

  /**
   * Return true if the given row is selected.
   */
  virtual bool IsRowSelected(uint32_t aRowIdx) { return false; }

  /**
   * Return true if the given cell is selected.
   */
  virtual bool IsCellSelected(uint32_t aRowIdx, uint32_t aColIdx) {
    return false;
  }

  /**
   * Return the number of selected cells.
   */
  virtual uint32_t SelectedCellCount() { return 0; }

  /**
   * Return the number of selected columns.
   */
  virtual uint32_t SelectedColCount() { return 0; }

  /**
   * Return the number of selected rows.
   */
  virtual uint32_t SelectedRowCount() { return 0; }

  /**
   * Get the set of selected cells.
   */
  virtual void SelectedCells(nsTArray<Accessible*>* aCells) = 0;

  /**
   * Get the set of selected cell indices.
   */
  virtual void SelectedCellIndices(nsTArray<uint32_t>* aCells) = 0;

  /**
   * Get the set of selected column indices.
   */
  virtual void SelectedColIndices(nsTArray<uint32_t>* aCols) = 0;

  /**
   * Get the set of selected row indices.
   */
  virtual void SelectedRowIndices(nsTArray<uint32_t>* aRows) = 0;

  /**
   * Select the given column unselecting any other selected columns.
   */
  virtual void SelectCol(uint32_t aColIdx) {}

  /**
   * Select the given row unselecting all other previously selected rows.
   */
  virtual void SelectRow(uint32_t aRowIdx) {}

  /**
   * Unselect the given column leaving other selected columns selected.
   */
  virtual void UnselectCol(uint32_t aColIdx) {}

  /**
   * Unselect the given row leaving other selected rows selected.
   */
  virtual void UnselectRow(uint32_t aRowIdx) {}

  /**
   * Return true if the table is probably for layout.
   */
  virtual bool IsProbablyLayoutTable();

  /**
   * Convert the table to an Accessible*.
   */
  virtual Accessible* AsAccessible() = 0;

  typedef nsRefPtrHashtable<nsPtrHashKey<const TableCellAccessible>, Accessible>
      HeaderCache;

  /**
   * Get the header cache, which maps a TableCellAccessible to its previous
   * header.
   * Although this data is only used in TableCellAccessible, it is stored on
   * TableAccessible so the cache can be easily invalidated when the table
   * is mutated.
   */
  HeaderCache& GetHeaderCache() { return mHeaderCache; }

 protected:
  /**
   * Return row accessible at the given row index.
   */
  Accessible* RowAt(int32_t aRow);

  /**
   * Return cell accessible at the given column index in the row.
   */
  Accessible* CellInRowAt(Accessible* aRow, int32_t aColumn);

 private:
  HeaderCache mHeaderCache;
};

}  // namespace a11y
}  // namespace mozilla

#endif