FieldType's element attribute is null
Found a solution by how Entry Form handles it.

Assuming you've posted fields with names such as jobData[reference]:

$fieldsLocation = craft()-&gt;request-&gt;getParam('fieldsLocation', 'jobData');

$this-&gt;entry-&gt;setContentFromPost($fieldsLocation);


The setContentFromPost() method of the EntriesController class sets the ElementType.