PostingReadTable::onAfterAdd

static function onAfterAdd(EntityEvent $event)
{
	$result = new EntityEventResult;
	$data = $event->getParameters();
	$data = $data['fields'];

	// update read flag of recipient
	ModelPostingRecipientTable::update($data['RECIPIENT_ID'], ['IS_READ' => 'Y']);

	// update read counter of posting
	$resultDb = static::getList(array('filter' => array('RECIPIENT_ID' => $data['RECIPIENT_ID'])));
	if($resultDb->getSelectedRowsCount() == 1)
	{
		ModelPostingTable::update($data['POSTING_ID'], array(
			'COUNT_READ' => new BitrixMainDBSqlExpression('?# + 1', 'COUNT_READ')
		));
	}

	return $result;
}