Implementing IDataSource

[Andrew]

I need my own datasource control to connect to my business objects.

Interestingly when I implemented a descendant of
System.Web.UI.DataSourceControl it would never show up on my toolbox so I
have implemented System.Web.UI.Control descendant that supports the
System.Web.UI.IDataSource interface.

This works and I can connect my data source control up to grids etc and it
works fine.

The only problem is at design time it does not allow me to pick data fields
from a drop down list. I have to type in the field names manually.

Do I have to implement another interface other than IDataSource to make it
show the available fields in a drop down list at design time?

Thanks