Customizing the metamodel : Keywords for USRPROPS : LIST
  
LIST
The list keyword has two purposes in USRPPROPS.TXT. The default length for a LIST property is 1200.
Purpose 1: List of possible values
The LIST keyword establishes a list of possible text values. It must be defined in two places – at the top of the USRPROPS.TXT file, wherein you specify the list of possible values, and in the property that is using the list. All List specification statements must be at the top of the USRPROPS.TXT file, before any DIAGRAM, DEFINITION, or SYMBOL specification statements.
Example
List "Method Stereotypes"
{
VALUE "Get"
VALUE "Let"
VALUE "Set"
}
DEFINITION "Method" {..
PROPERTY "Stereotype" { EDIT Text LIST "Method Stereotypes"
Default "" LENGTH 30 } ...}
Radio buttons versus drop-down list
if the number of values in the LIST statement is four or less, they are displayed as radio button choices.
If the number of values is five or more, they are displayed in a drop-down list.
Users may type in their own value in a drop-down list box.
If you want a dropdown list when there are four or less LIST values, use the LISTONLYCOMBO keyword.
Purpose 2: DISPLAY FORMAT argument
The LIST keyword is also one of the allowed arguments following FORMAT in the DISPLAY command. The LIST keyword causes items to be displayed on the symbol in a list. Each whitespace character causes a new line, unless the whitespace is in double quotation mark bounds.
Example
DEFINITION "Operational Node"{ PROPERTY "Operational Activities" {EDIT LISTOF "Operational Activity" LENGTH 2000 DISPLAY {FORMAT LIST Legend "Activities"} ..}