private void OnAddPhoneNumberExecute()
        {
            var newNumber = new ClientPhoneNumberWrapper(new ClientPhoneNumber());

            newNumber.PropertyChanged += ClientPhoneNumberWrapper_PropertyChanged;
            PhoneNumbers.Add(newNumber);
            Client.Model.PhoneNumbers.Add(newNumber.Model);
            newNumber.Number = ""; //Trigger validation;
        }
 private void InitializeClientPhoneNumbers(ICollection <ClientPhoneNumber> phoneNumbers)
 {
     foreach (var wrapper in PhoneNumbers)
     {
         wrapper.PropertyChanged -= ClientPhoneNumberWrapper_PropertyChanged;
     }
     PhoneNumbers.Clear();
     foreach (var clientPhoneNumber in phoneNumbers)
     {
         var wrapper = new ClientPhoneNumberWrapper(clientPhoneNumber);
         PhoneNumbers.Add(wrapper);
         wrapper.PropertyChanged += ClientPhoneNumberWrapper_PropertyChanged;
     }
 }