Question

I am using ListViewCollection class with my dataGrid. The underlying collection is an observable collection.

Whenever i call Move methods in the collection ( which is in ViewModel), the CurrentChanged Event doesnt fire.

However when UI calls the same method on it ( i can see it in the call stack), the event does fire.

  this.EmailTemplates = new ListCollectionView(templateVmList);
  this.EmailTemplates.CurrentChanging += (o, e) => EmailTemplates_CurrentChanging(o, e);
  this.EmailTemplates.CurrentChanged += (o, e) => { this.SelectedEmailTemplate = (EmailTemplateViewModel)this.EmailTemplates.CurrentItem; };
  if (this.EmailTemplates.Count > 0)
  {
       if (!this.EmailTemplates.MoveCurrentToFirst())
            throw new ArgumentException("Element not found in collection");             
  }

What should i do in code to make sure the events fire no matter who is changing the collection.

Answer 1

Try using CollectionViewSource.GetDefaultView instead of creating a new ListCollectionView.

This test code worked fine for me

public class LcViewModel : BaseItemsViewModel
{
    public LcViewModel()
    {
        MoveCommand = new RelayCommand(Move);

        var view = CollectionViewSource.GetDefaultView(Items);
        view.CurrentChanged += (sender, args) => Debug.WriteLine("CurrentChanged");
        view.CurrentChanging += (sender, args) => Debug.WriteLine("CurrentChanging");
    }

    public ICommand MoveCommand { get; private set; }

    private void Move()
    {
        var view = CollectionViewSource.GetDefaultView(Items);
        view.MoveCurrentToFirst();
    }
}