I need to add a upload button in a custom create-form template. This form is used for create a new data-list item, and I need to upload one or more files that are associated with this item. I know that I can config a custom control template for each property (or association), for example, the association control template (association.ftl) allows you to choose a file from the repository, but I need to UPLOAD a new file from my pc and then these files will be associated with the item (for example, by a custom form processor, when the item is persisted). In conclusion, my problem is that I don't know how to create a button with the upload function in my create form. Any help?