Hi,

I've been attempting to bind a heterogeneous collection (it's a class hierarchy with only two levels) to the XamDataGrid using an ObjectDataProvider instance.

While this works fine, the grid generates a column header for each row, as the types differ. What I would like to do is generate a single header that contains required columns for all data types within the collection and have empty or greyed out cells for the columns that don't apply to the type in question.

For example:

interface IVehicle
{
  string Manufacturer { get; }
  string Model { get; }
}

interface ICar : IVehicle
{
  int Doors { get; }
}

interface IBoat : IVehicle
{
  int NumEngines { get; }
}

Displayed as:

Handling the AssigningFieldLayoutToItem event and specifying the same FieldLayout would be ideal, if it were not for the fact that all fields must exist on every object (the docs mention an exception is thrown if this isn't the case).

While I could provide a view model which wraps around every IVehicle derived type and exposes all properties, this is rather time consuming and makes maintenance difficult. Unlike the vehicle example above, my model contains 7 dervived types all of which have between 5 and 10 unique properties. That, and the properties will (and are) changing during development.

Is there a way to attempt to assign a single FieldLayout and prevent exceptions from being thrown?

Alternative suggestions welcome.

Thanks in advance,

Andrew