How to pass a Document File to UIActivityViewController i.e. Share Sheet

I have an iOS App which generates a CSV File and saves it to the working Documents directory of the device. Now when a user presses a button, the UIActivityViewController Share Sheet is displayed which allows you to open send data to other apps.

My question is how do I pass this CSV file to the Share Sheet. I know how to make this work with Text and Images, but not exactly sure how to get this to work with a CSV file. The end result is that I want this file to show up as an attachment in any email client which is selected from the Share Sheet.

This is the code I use to open a document (word, pdf, etc.). Should work for you...

@IBAction func openDocument(sender: AnyObject)
{
    let interactionController = UIDocumentInteractionController(URL: documentURL)

    // (build your document's URL from its path in the Documents directory)

    interactionController.delegate = self


    // First, attempt to show the "Open with... (app)" menu. Will fail and
    // do nothing if no app is present that can open the specified document
    // type.

    let result = interactionController.presentOpenInMenuFromRect(
        self.view.frame,
        inView: self.view,
        animated: true
    )


    if result == false {

        // Fall back to "options" view:

        interactionController.presentOptionsMenuFromRect(
            self.view.frame,
            inView: self.view,
            animated: true)
    }

    // DONE
}