jquery ui already place on page in header, but the builder is trying to add it again

[GoogleCodeExporter]

What steps will reproduce the problem?
1.Include a header that has jquery and jquery ui
2.make a form with your form builder
3.view the page

What is the expected output? What do you see instead?
The expected output is no errors, but what I get is a javascript error. Why? 
Because I already loaded jquery and jquery ui in the header included in our 
website, but the php form builder is trying to put the jquery-ui on the page 
again. By doing this, it is causing an error.

What version of the product are you using? On what operating system?
pfbc3.1-php5.zip

Please provide any additional information below.

Original issue reported on code.google.com by rjacobse...@gmail.com on 21 Jan 2013 at 5:16

[GoogleCodeExporter]

I have found that this only occurs when running any of the 4 following lines:

$form->addElement(new Element_HTML('<legend>jQuery UI</legend>'));
$form->addElement(new Element_jQueryUIDate("Date:", "jQueryUIDate"));
$form->addElement(new Element_Checksort("Checksort:", "Checksort", $options));
$form->addElement(new Element_Sort("Sort:", "Sort", $options));

Original comment by rjacobse...@gmail.com on 21 Jan 2013 at 5:21

[GoogleCodeExporter]

r611 added support for "jqueryui" as a value in the prevent array - which is 
used to prevent assets from being loaded (like jquery, bootstrap, and now 
jqueryui).

See http://code.google.com/p/php-form-builder-class/source/detail?r=611 for 
details.

Original comment by ajporterfield@gmail.com on 12 Feb 2013 at 4:44

[GoogleCodeExporter]

How is one supposed to set those values? There doesn't seem to be a 
setPrevent() method.

Original comment by gms8...@gmail.com on 13 Mar 2013 at 12:26