v4.0
Returns or sets a String value
representing the label of the item. For many controls this text
appears to the left of the control. When not specified the name of
the parameter (see SIObject.Name)
or Parameter.ScriptName
will be displayed.
This attribute is optional for Groups and Buttons and mandatory for
Tabs. See PPGLayout.AddGroup,
PPGLayout.AddButton and
PPGLayout.AddTab.
To draw a control without any label use the siUINoLabel or
siUIValueOnly flags (see siPPGItemAttribute).