# V

`+Val`
  Takes a function that gets called each time a field's value is retrieved. The following example returns the square of the field's value:

          (gui '(+Val +NumField) '((N) (* N N)) 10)

  See also +Set, +Fmt, Formatting.

`+Var`
  Links a form field to a variable.

          "Occupation" (gui 'job '(+Var +TextField) '*PrsJob 20)

  This example links a text field to the variable *PrsJob. See also +E/R.

`+View`
  Like `+Lock`, view is a prefix class that disables a GUI component. However, `+View` can take a functional argument:

          (gui '(+Sgn +View +FixField) '(sum> (: home obj)) 2 12) ) )

  This example is a snippet from the demo app included with the PicoLisp distribution, in ord.l. The code produces a disabled text field that displays the total order sum of the current order object. See also +Lock, +Upd, +Init.