You can mark fields as valid or invalid in the generated application.
Variable
ctrl
the current field, a Control object.
Functions
ctrl.setInvalid( message )
Marks the control invalid.
ctrl.setValid()
Marks the control valid.
Note: setValid() only removes the status set by setInvalid(), it has no effect on other validations.
Note: the page can not be saved when there are invalid fields on it.
Example
if( ctrl.getValue() > 100 )
ctrl.setInvalid( 'Price can not exceed 100' );
else
ctrl.setValid();
See also:
•JavaScript API: Control object > getValue()
•JavaScript API: RunnerPage object > hideField()
•JavaScript API: RunnerPage object > showField()