Another variation of a combo box is where you want to present the user with the appearance of there being a combo box to select from, but you do not want to specify the choices in advance. One reason might be that the choices are actually all the records in a file, and rather than fetch them in advance, you want to allow the user to enter a couple of characters to limit the number of choices, then presenting them in an XTREE control (which is equipped to handle thousands of entries, unlike the combo box). To get this effect, specify SETDEF="..." (3 dots). INFLD will then return EXITCODE 29 to the application when the user clicks on the Down-Arrow button or hits a key that would normally display the list (including the Down-Arrow key)
