public void ApplyChanges()
        {
            DegreeAfter  = DegreeAfter.Trim();
            DegreeBefore = DegreeBefore.Trim();
            FirstName    = FirstName.Trim();
            MiddleName   = MiddleName.Trim();
            SurName      = SurName.Trim();

            if (_degreeAfter != null)
            {
                _speaker.DegreeAfter = _degreeAfter;
            }
            if (_degreeBefore != null)
            {
                _speaker.DegreeBefore = _degreeBefore;
            }
            if (_firstName != null)
            {
                _speaker.FirstName = _firstName;
            }
            if (_imgBase64 != null)
            {
                _speaker.ImgBase64 = _imgBase64;
            }
            if (_language != null)
            {
                _speaker.DefaultLang = _language;
            }
            if (_pinned != null)
            {
                _speaker.PinnedToDocument = _pinned.Value;
            }
            if (_middleName != null)
            {
                _speaker.MiddleName = _middleName;
            }
            if (_sex != null)
            {
                _speaker.Sex = _sex.Value;
            }
            if (_surName != null)
            {
                _speaker.Surname = _surName;
            }
            if (_pinned != null)
            {
                _speaker.PinnedToDocument = _pinned.Value;
            }


            foreach (var att in _RemovedAttributes)
            {
                _speaker.Attributes.Remove(att);
            }

            _speaker.Attributes.AddRange(_AddedAttributes);

            _OriginalAttributes = _speaker.Attributes.Select(a => new SpeakerAttribute(a)).ToList();;
            //changes should be discarded after applying
            DiscardChanges();

            Changed = false;
            New     = false;
        }
        private async void RegisterUser()
        {
            if (await CheckUser() == true)
            {
                Users tempUser = new Users(0, Password, int.Parse(MobileNr.Trim()), FirstName.Trim(), SurName.Trim(), Email.Trim(), null);

                if (await services.AddUser(tempUser) == true)
                {
                    IsRegisterComplete = true;
                    await navigation.PopToRootAsync();
                }
            }
        }