ios - 在 Swift 中发送应用程序电子邮件

Question

在 Swift 中执行此操作时遇到问题。在 Objective C 中非常容易。我在日志中得到的错误是这样的:

2015-01-31 22:16:58.734 fun facts[15208:623304] Unknown class Settings in Interface Builder file.
2015-01-31 22:17:10.783 fun facts[15208:623304] -[UIViewController sendEmail:]: unrecognized selector sent to instance 0x7f9b7bc2fa30
2015-01-31 22:17:10.794 fun facts[15208:623304] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIViewController sendEmail:]: unrecognized selector sent to instance 0x7f9b7bc2fa30'

请参阅下面的代码。知道我做错了什么吗？

//////////////////////SEND EMAIL


    @IBAction func sendEmail(sender: AnyObject) {

        var emailTitle = "Test Email"
        var messageBody = "This is a test email body"
        var toRecipents = ["yolo@mail.com"]
        var mc: MFMailComposeViewController = MFMailComposeViewController()
        mc.mailComposeDelegate = self
        mc.setSubject(emailTitle)
        mc.setMessageBody(messageBody, isHTML: false)
        mc.setToRecipients(toRecipents)

        self.presentViewController(mc, animated: true, completion: nil)
    }



    func mailComposeController(controller:MFMailComposeViewController, didFinishWithResult result:MFMailComposeResult, error:NSError) {
        switch result.value {
        case MFMailComposeResultCancelled.value:
            println("Mail cancelled")
        case MFMailComposeResultSaved.value:
            println("Mail saved")
        case MFMailComposeResultSent.value:
            println("Mail sent")
        case MFMailComposeResultFailed.value:
            println("Mail sent failure: \(error.localizedDescription)")
        default:
            break
        }
        self.dismissViewControllerAnimated(false, completion: nil)
}

}

Answer 1

如果您不小心将 View 的类设置为不兼容的自定义类，就会发生这种错误；例如，不小心将 UIButton 的自定义类设置为“Settings”，即本例中的 UIViewController 类，可能会导致您的特定错误。