public SessionViewModel(SessionModel model ,IPersonFactory<Person> personFactory)
{
_model = model.ThrowIfNull("model");
_personFactory = personFactory.ThrowIfNull("personFactory");
AddNewPersonCommand = new ReactiveCommand();
AddNewPersonCommand.Subscribe(dontcare =>
_model.Participants.Add(_personFactory.GetNewPerson(Participants.Count)));
Participants = _model.Participants
.CreateDerivedCollection(x => new ParticipantViewModel(x));
Participants.ChangeTrackingEnabled = true;
var deleteCanExecute = Observable.Merge(Participants.ItemChanged
.Select(_ => Participants.Any(p => p.IsSelected)),
Participants.CollectionCountChanged
.Select(_ => Participants.Any(p=> p.IsSelected)));
DeleteSelectedCommand = new ReactiveCommand
(
deleteCanExecute
);
DeleteSelectedCommand.Subscribe(
x =>
{
RemoveSelected();
}
);
AddNewPersonCommand.Execute(null);
}