private void  BuildDataFieldList()
        {
            int origWindowHeight        = this.Height;
            int origDataFieldListHeight = DataFieldList.Height;

            int origWindowWidth        = this.Width;
            int origDataFieldListWidth = DataFieldList.Width;

            int fieldNum = 0;

            for (fieldNum = 0; fieldNum < PicesInstrumentData.NumFields(); fieldNum++)
            {
                DataFieldList.Items.Add(PicesInstrumentData.FieldName(fieldNum));
            }
            DataFieldList.SelectedItem = selectedDataField;

            int totalHeightNeeded = PicesInstrumentData.NumFields() * DataFieldList.ItemHeight + 30;

            DataFieldList.Height = totalHeightNeeded;

            int newWindowHeight = DataFieldList.Height + (origWindowHeight - origDataFieldListHeight);
            int newWindowWidth  = DataFieldList.Width + (origWindowWidth - origDataFieldListWidth);

            this.Height = newWindowHeight;
            this.Width  = newWindowWidth;
        }