Method _handleArrowAlt

packages/compat/src/Table.ts:702–736

* Handles Alt + Up/Down. * Switches focus between column header, last focused item, and "More" button (if applicable). * @private

(e: KeyboardEvent)

	 * @private
	 */
	_handleArrowAlt(e: KeyboardEvent) {
		const shouldMoveUp: boolean = isUpAlt(e);
		const target = e.target as ITableRow;
		const focusedElementType = this.getFocusedElementType(target);

		if (shouldMoveUp) {
			switch (focusedElementType) {
			case TableFocusTargetElement.Row:
			case TableFocusTargetElement.GroupRow:
				this._prevFocusedRow = target;
				return this._onColumnHeaderClick(e);
			case TableFocusTargetElement.ColumnHeader:
				return this.morеBtn ? this.morеBtn.focus() : this._prevFocusedRow?.focus();
			case TableFocusTargetElement.MoreButton:
				return this._prevFocusedRow ? this._prevFocusedRow.focus() : this._onColumnHeaderClick(e);
			}
		} else {
			switch (focusedElementType) {
			case TableFocusTargetElement.Row:
			case TableFocusTargetElement.GroupRow:
				this._prevFocusedRow = target;
				return this.morеBtn ? this.morеBtn.focus() : this._onColumnHeaderClick(e);
			case TableFocusTargetElement.ColumnHeader:
				if (this._prevFocusedRow) {
					this._prevFocusedRow.focus();
				} else if (this.morеBtn) {
					this.morеBtn.focus();
				}

				return;
			case TableFocusTargetElement.MoreButton:
				return this._onColumnHeaderClick(e);
			}
		}
	}

	/**
	 * Determines the type of the currently focused element.