Genie and certain 5250 emulators implement Single-Choice fields (SNGCHCFLD) using radio buttons. In user-interfaces, one button in a group of radio buttons should always be selected.
Web browsers do not allow users to uncheck radio buttons, whereas certain 5250 emulators do allow unchecking.
Instead of expecting the interface to allow radio buttons to be unchecked, developers should offer an additional button. When checked, this button's value indicates that none of the other options were selected–a value of blank, for example.
However, legacy applications may have been designed with an untold number of screens that rely on being able to deselect a group of SNGCHCFLD fields. To support these applications, Genie can be configured to allow unchecking of radio buttons.
Example Configuration Option