if ([self.txtOutputTranslator baseWritingDirectionForPosition:[self.txtOutputTranslator beginningOfDocument] inDirection:UITextStorageDirectionForward] == UITextWritingDirectionLeftToRight)
{
    self.txtOutputTranslator.textAlignment=NSTextAlignmentLeft;
}
else
{
    self.txtOutputTranslator.textAlignment=NSTextAlignmentRight;

}

func textViewDidChange(_ textView: UITextView) {
    let baseWritingDirection = textView.baseWritingDirection(for: textView.beginningOfDocument, in: .forward)
    switch baseWritingDirection {
    case .leftToRight:
        textView.textAlignment = .left // for example
    case .rightToLeft:
        textView.textAlignment = .right // for example
    case .natural:
        // WARNING: use natural alignment carefully as it won't work with reusable table view cells. In common cases baseWritingDirection won't return this parameter
        textView.textAlignment = .natural
    }
}