/**
* Gets a help text by field name.
*
* @param string $name The field name (required - the default value is here because PHP do not allow signature changes with inheritance)
*
* @return string The help text or an empty string if it is not defined
*
* @throws InvalidArgumentException when you try to get a help for a none existing widget
*/
public function getHelp($name = null)
{
if (1 == func_num_args()) {
if (!isset($this->fields[$name])) {
throw new InvalidArgumentException(sprintf('Unable to get the help on an unexistant widget ("%s").', $name));
}
return $this->fields[$name]->getHelp();
} else {
// help for this widget schema
return parent::getHelp();
}
}
