def is_valid_input(self) -> bool:
        is_valid = True
        if not self.ui.txt_name.text():
            self._error_message += "Student name is missing.\n"
            is_valid = False

        if not self.ui.txt_surname.text():
            self._error_message += "Student surname is missing.\n"
            is_valid = False

        if not self.ui.txt_email.text():
            self._error_message += "Student email is missing.\n"
            is_valid = False
        elif not re.match(r"[^@]+@[^@]+\.[^@]+", self.ui.txt_email.text()):
            self._error_message += "Email address is invalid.\n"
            is_valid = False

        return is_valid