I have an ultra combo editor that is setup to allow mulitple selections. I am having two problems with it that need to be resolved:
When I included the null text as part of data filter it showed up when it should as I expected.
1. I was not able to reproduce this; I set the NullText property and when all checkboxes were unchecked, that string was displayed when the control lost focus.
2. There is no intrinsic support for this; you could, however, use the Infragistics.Win.IEditorDataFilter interface to change what the editor displays.