I have created a custom filelist form field. 
Field is used in a repeatable subform.
The purpose of this custom form field is to display list of files in folder based on 'name' field in main form.
The problem I've encountered is how to get the 'name' field from the custom form field to redirect to specific folder.
The form object ($this->form) is the subform object.
How to access the main form / parent form fields to get the required 'name' field value?