Crio um arquivo csv e tento enviá-lo por email. Exibe uma janela para enviar email, mas não é preenchida com o corpo do email e sem arquivo anexado. O aplicativo trava com esta tela:

botão "Cancelar" não funciona. Após alguns segundos, o console aparece:

viewServiceDidTerminateWithError: Error Domain=_UIViewServiceInterfaceErrorDomain Code=3 "The operation couldn’t be completed. (_UIViewServiceInterfaceErrorDomain error 3.)" UserInfo=0x7f8409f29b50 {Message=Service Connection Interrupted}

<MFMailComposeRemoteViewController: 0x7f8409c89470> timed out waiting for fence barrier from com.apple.MailCompositionService

Aqui está o meu código:

func actionSheet(actionSheet: UIActionSheet!, clickedButtonAtIndex buttonIndex: Int) {
    if buttonIndex == 0 {
        println("Export!")

        var csvString = NSMutableString()
        csvString.appendString("Date;Time;Systolic;Diastolic;Pulse")

        for tempValue in results {     //result define outside this function

            var tempDateTime = NSDate()
            tempDateTime = tempValue.datePress
            var dateFormatter = NSDateFormatter()
            dateFormatter.dateFormat = "dd-MM-yyyy"
            var tempDate = dateFormatter.stringFromDate(tempDateTime)
            dateFormatter.dateFormat = "HH:mm:ss"
            var tempTime = dateFormatter.stringFromDate(tempDateTime)

            csvString.appendString("\n\(tempDate);\(tempTime);\(tempValue.sisPress);\(tempValue.diaPress);\(tempValue.hbPress)")
        }

        let fileManager = (NSFileManager.defaultManager())
        let directorys : [String]? = NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory.DocumentDirectory,NSSearchPathDomainMask.AllDomainsMask, true) as? [String]

        if ((directorys) != nil) {

            let directories:[String] = directorys!;
            let dictionary = directories[0];
            let plistfile = "bpmonitor.csv"
            let plistpath = dictionary.stringByAppendingPathComponent(plistfile);

            println("\(plistpath)")

            csvString.writeToFile(plistpath, atomically: true, encoding: NSUTF8StringEncoding, error: nil)

            var testData: NSData = NSData(contentsOfFile: plistpath)

            var myMail: MFMailComposeViewController = MFMailComposeViewController()

            if(MFMailComposeViewController.canSendMail()){

                myMail = MFMailComposeViewController()
                myMail.mailComposeDelegate = self

                // set the subject
                myMail.setSubject("My report")

                //Add some text to the message body
                var sentfrom = "Mail sent from BPMonitor"
                myMail.setMessageBody(sentfrom, isHTML: true)

                myMail.addAttachmentData(testData, mimeType: "text/csv", fileName: "bpmonitor.csv")

                //Display the view controller
                self.presentViewController(myMail, animated: true, completion: nil)
            }
            else {
                var alert = UIAlertController(title: "Alert", message: "Your device cannot send emails", preferredStyle: UIAlertControllerStyle.Alert)
                alert.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.Default, handler: nil))
                self.presentViewController(alert, animated: true, completion: nil)


            }
        }
        else {
            println("File system error!")
        }
    }
}

Tentando enviar e-mail usandoUIActivityViewController:

let fileURL: NSURL = NSURL(fileURLWithPath: plistpath)
let actViewController = UIActivityViewController(activityItems: [fileURL], applicationActivities: nil)
self.presentViewController(actViewController, animated: true, completion: nil)

Veja aproximadamente a mesma tela para enviar e-mail, que depois de um tempo retornando à tela anterior. No console, agora outro erro:

viewServiceDidTerminateWithError: Error Domain=_UIViewServiceInterfaceErrorDomain Code=3 "The operation couldn’t be completed. (_UIViewServiceInterfaceErrorDomain error 3.)" UserInfo=0x7faab3296ad0 {Message=Service Connection Interrupted}
Errors encountered while discovering extensions: Error Domain=PlugInKit Code=13 "query cancelled" UserInfo=0x7faab3005890 {NSLocalizedDescription=query cancelled}
<MFMailComposeRemoteViewController: 0x7faab3147dc0> timed out waiting for fence barrier from com.apple.MailCompositionService

Havia algo sobrePlugInKit.

TentandoUIActivityViewController usandoUIDocumentInteractionController:

let docController = UIDocumentInteractionController(URL: fileURL)
docController.delegate = self
docController.presentPreviewAnimated(true)
...

func documentInteractionControllerViewControllerForPreview(controller: UIDocumentInteractionController!) -> UIViewController! {
    return self
}

Eu vejo essa tela com o conteúdo de um arquivo CSV:http://prntscr.com/4ilgax Pressiono o botão Exportar no canto superior direito e vejo esta telahttp://prntscr.com/4ilguk onde eu escolho MAIL e e por alguns segundos eu vejohttp://prntscr.com/4ilh2h Em seguida, volta a exibir o conteúdo do arquivo! No console, as mesmas mensagens que ao usarUIActivityViewController.