I have an UltraGrid that uses a generic list for a DataSource.  I update the list in a separate form and then re-attach the list to the UltraGrid's DataSource.  The DataSource reflects the changes, but the grid isn't showing them.  Here is my code:

List<SubtypeColorCode> subtypeColorCodes;
 
            if (this.subtypeColorCodesUltraGrid.DataSource is List<SubtypeColorCode>)
                subtypeColorCodes =
                   (List<SubtypeColorCode>)this.subtypeColorCodesUltraGrid.DataSource;
            else
                //If the data source hasn't been initialized.
                subtypeColorCodes = new List<SubtypeColorCode>();
 
            SubtypeColorCodeForm.ShowForm(this, new ImageServerProxy(this.tbImagingUri.Text),
                subtypeColorCodes);
 
            //Assign the updated subtype list back to the data source.
            this.subtypeColorCodesUltraGrid.DataSource = subtypeColorCodes;