private async void _saveButton_Clicked(object sender, EventArgs e)
{
Employee employee = new Employee()
{
Name = _nameEntry.Text,
Address = _address.Text,
Company = _company.Text,
Email = _email.Text,
Designation = _designation.Text
};
await _restService.CreateEmployeeAsyn(employee);
await DisplayAlert(null, employee.Name + " saved", "OK");
await Navigation.PopAsync();
}