This returns the "selected" value in a widget (if applicable), or
its main property. Selection varies from widget to widget, but
should generally be what can be added to the widget by mouse click
or typing. For some widgets, the extra argument index=TRUE
will return the index of the selected value, not the value. For
some widget, the argument drop is given to either prevent
or encourage dropping of information.
Calls coerce_with when available. This value is a function
and may be set as any property if the constructor does not
explicity provide it.
This method sets the selected value of, or main property of the widget.
For gformlayout the svalue assigment method takes a
named list and calls svalue<- on the children with matching
names.
svalue(obj, index = FALSE, drop = NULL, ...)# S3 method for default
svalue(obj, index = NULL, drop = NULL, ...)
svalue(obj, index=NULL, ...) <- value
svalue(obj, index=NULL, ...) <- value
# S3 method for GFormLayout
svalue (obj, index=NULL, ...) <- value
object of method call
NULL or logical. If TRUE and widget supports it an index, instead of a value will be returned.
NULL or logical. If widget supports it, drop will work as it does in a data frame or perhaps someother means.
passed on to call
value to assign for selection or property
THe return value varies, depending if the widget is a
"selection" widget or not. For non-selection widgets, the main
property is loosely defined (the title of a window, text of a
label or button, spacing of box containers, ...). For selection
widgets the return value is the currently selected value. If no
selection is made, this will be a 0-length vector with the
expected class, if possible. For selection widgets, when
index=TRUE, the value is an integer, possible 0-length when
non selection is made.