MvxPickerViewModel Bind to Property of an Object - xamarin.ios

Question

I have following code:
var pickerViewModel = new MvxPickerViewModel(this.mandantenPicker);
this.mandantenPicker.Model = pickerViewModel;
this.mandantenPicker.ShowSelectionIndicator = true;
mandantenAuswahlTextfield.InputView = this.mandantenPicker;
var set = this.CreateBindingSet<LoginView, LoginViewModel>();
set.Bind(pickerViewModel).For(p => p.SelectedItem).To(vm => vm.SelectedMandant);
set.Bind(pickerViewModel).For(p => p.ItemsSource).To(vm => vm.Mandanten);
set.Apply();
In the PickerView I don't have the expected values. Its showing the namespace of the object.
I'm binding to a list of "Mandants", a Mandant has FirstName/LastName. How can I set the "to be showed" value?
So something like:
set.Bind(pickerViewModel).For(p => p.ItemsSource).To(vm => vm.Mandanten)["FirstName"]; //stupid example but to show better what I mean/want

Answer 1

The MvxPickerViewModel currently uses GetTitle() to work out what to display:
public override string GetTitle(UIPickerView picker, int row, int component)
{
return _itemsSource == null ? "-" : RowTitle(row, _itemsSource.ElementAt(row));
}
protected virtual string RowTitle(int row, object item)
{
return item.ToString();
}
from https://github.com/slodge/MvvmCross/blob/v3/Cirrious/Cirrious.MvvmCross.Binding.Touch/Views/MvxPickerViewModel.cs
If you wanted to customise the strings displayed, you could:
inherit from MvxPickerViewModel and provide an override for RowTitle:
protected override string RowTitle(int row, object item)
{
return ((Mandant)item).FirstName;
}
or override the ToString in your Mandant object
or provide and use some ValueConverters from IEnumerable<Mandant> to IEnumerable<WrappedMandant> and Mandant to WrappedMandant where WrappedMandant provides the ToString() implementation you want to use:
public class WrappedMandant
{
public Mandant Mandant { get;set;}
public override string ToString()
{
return Mandant.FirstName;
}
}
If you wanted to customise the picker cells displayed further, then you could also override GetView and them provide a custom cell for each Mandant