public LoginPage(IUserRepository userRepository = null, INotifyPage notifyPage = null, IValuesRepository valuesRepository = null)
{
_userRepository = userRepository ?? DependencyService.Get<IUserRepository>();
_notifyPage = notifyPage ?? new NotifyPage(this);
_valuesRepository = valuesRepository ?? DependencyService.Get<IValuesRepository>();
_userLoginModel = _userRepository.GetUserLoginModel();
BindingContext = _userLoginModel;
InitializeComponent();
}