MFMailComposeViewController 委托未在 swift 4 上工作

MFMailComposeViewController delegate not working on swift 4

我正在尝试关闭 MFMailComposeViewController,但未触发委托。这似乎是一个常见问题,答案是相同的,但它们对我不起作用:(。我有一个按钮调用发送邮件的功能。我首先创建一个 csv 文件,然后创建 MFMailComposeViewController 并附上csv 文件发送到邮件。有时会发送邮件(之后邮件视图控制器不会关闭),取消按钮显示删除或保存草稿的选项,但之后没有任何反应。

按钮代码如下:

import UIKit
import MessageUI

class UserInfoViewController: UIViewController, MFMailComposeViewControllerDelegate {

@IBAction func uploadPressed(_ sender: Any) {

        let contentsOfFile = "Name,ID,Age,Sex,Time,\n\(name),\(id),\(age),\(sex),\(time)"

        let data = contentsOfFile.data(using: String.Encoding.utf8, allowLossyConversion: false)

        if let content = data {
            print("NSData: \(content)")
        }

        func configuredMailComposeViewController() -> MFMailComposeViewController {

            let emailController = MFMailComposeViewController()

            //emailController.mailComposeDelegate = self as? MFMailComposeViewControllerDelegate
            emailController.mailComposeDelegate = self
            emailController.setToRecipients([""])
            emailController.setSubject("CSV File")
            emailController.setMessageBody("", isHTML: false)

            emailController.addAttachmentData(data!, mimeType: "text/csv", fileName: "registro.csv")

            return emailController

        }

        let emailViewController = configuredMailComposeViewController()

        if MFMailComposeViewController.canSendMail() {

            self.present(emailViewController, animated: true, completion: nil)

        }

        func mailComposeController(_ controller: MFMailComposeViewController, didFinishWith result: MFMailComposeResult, error: Error?) {

            print("Delegate worked!")
            controller.dismiss(animated: true, completion: nil)

        }

    }
}

非常感谢您。

您的问题是由于将委托方法放在另一个方法中引起的。你不能那样做。委托函数需要位于 class 的顶层。只需将 mailComposeController(_:didFinishWith:error:) 函数移出 uploadPressed 函数即可。