2-Way databinding with Entity Framework and WPF DataGrid

Question

I'm having trouble adding an Entity Framework entity to a ObjectContext's EntitySet automatically using the WPF 4.0 DataGrid's add functionality. Here's the setup:

DataGrid-->BoundTo-->ListCollectionView-->BoundTo-->EntitySet

When I interactively add a row to the DataGrid, the EntitySet does not have a new entity added to it. Updating the row's cell data does in fact update the bound entity's properties, however.

Any idea what I could be doing wrong?

Here is the XAML for the ListCollectionView:

<CollectionViewSource x:Key="FieldList"
    Source="{Binding DB.Fields}"
    CollectionViewType="{x:Type data:ListCollectionView}">
    <CollectionViewSource.SortDescriptions>
        <ComponentModel:SortDescription PropertyName="Name" />
    </CollectionViewSource.SortDescriptions>
</CollectionViewSource>

Answer 1

Is there any particular reason why you are using ListCollectionView? How are you creating your ListCollectionView?

Calling CollectionViewSource.GetDefaultView( ObjectQuery<> ) yields a BindingListCollectionView. I have just run some tests and calling IEditableCollectionView.AddNew() and IEditableCollectionView.CommitNew() adds new entity to entity set as expected.

I suggest you simply bind your ObjectContext's ObjectQuery<> property to ItemsSource of a DataGrid and the default collection view will be used, ultimately giving you the behavior you expect.