Since decorators can target distinct metadata of the element or form they decorate, it's often useful to render one individual decorator at a time. This behavior is possible via method overloading in each major form class type (forms, sub form, display group, element).
To do so, simply call render[DecoratorName](), where
"[DecoratorName]" is the "short name" of your decorator; optionally,
you can pass in content you want decorated. For example:
<?php
// render just the element label decorator:
echo $element->renderLabel();
// render just the display group fieldset, with some content:
echo $group->renderFieldset('fieldset content');
// render just the form HTML tag, with some content:
echo $form->renderHtmlTag('wrap this content');
If the decorator does not exist, an exception is raised.
This can be useful particularly when rendering a form with the ViewScript decorator; each element can use its attached decorators to generate content, but with fine-grained control.