Method _getAriaSortAttribute

src/material/sort/sort-header.ts:207–213

* Gets the aria-sort attribute that should be applied to this sort header. If this header * is not sorted, returns null so that the attribute is removed from the host element. Aria spec * says that the aria-sort property should only be present on one header at a time, so removing * ensures

()

   * ensures this is true.
   */
  _getAriaSortAttribute() {
    if (!this._isSorted()) {
      return 'none';
    }

    return this._sort.direction == 'asc' ? 'ascending' : 'descending';
  }

  /** Whether the arrow inside the sort header should be rendered. */
  _renderArrow() {