ios - MFMailComposeViewController 不发送电子邮件或调用委托(delegate) (MFMailComposeViewControllerDelegate)

Question

我有一个 MFMailComposeViewController 设置并显示如下:

class MyViewController: UIViewController {

    // MARK: - Properties
    let composeViewController = MFMailComposeViewController()

    // MARK: - Actions
    @IBAction func didTapSendInEmailButton() {
        composeViewController.mailComposeDelegate = self
        composeViewController.setToRecipients([Constants.contactRecipientEmail])
        composeViewController.setSubject(Constants.contactSubject)
        composeViewController.setMessageBody(Constans.body, isHTML: false)
        present(composeViewController, animated: true, completion: nil)
    }
}

// MARK: - MFMailComposeViewControllerDelegate
extension MyViewController: MFMailComposeViewControllerDelegate {
    private func mailComposeController(_ controller: MFMailComposeViewController,
                                       didFinishWith result: MFMailComposeResult,
                                       error: Error?) {
        switch result {
        case .sent:
            print("Email sent")
        case .saved:
            print("Draft saved")
        case .cancelled:
            print("Email cancelled")
        case  .failed:
            print("Email failed")
        }
        controller.dismiss(animated: true, completion: nil)
    }
}

我遇到了这个问题:

1. 在编写器上按下“发送”后，不会调用 MFMailComposeViewControllerDelegate。

我可能遗漏了什么？

我无法将 mailComposeController 声明为公共(public):

Answer 1

我将在评论中强调一些小的变化:

import UIKit
import MessageUI

class MyViewController: UIViewController {

    // MARK: - Properties
    let composeViewController = MFMailComposeViewController()

    // MARK: - Actions
    @IBAction func didTapSendInEmailButton() {
        composeViewController.mailComposeDelegate = self
        // Entered a generic email in place of your constant value
        composeViewController.setToRecipients(["someone@example.com"])
        // Entered a generic subject in place of your constant value
        composeViewController.setSubject("subject")
        // You have a typo on "Constants" here
        composeViewController.setMessageBody("body", isHTML: false)
        present(composeViewController, animated: true, completion: nil)
    }
}

// MARK: - MFMailComposeViewControllerDelegate
extension MyViewController: MFMailComposeViewControllerDelegate {
    // Removed the private
    func mailComposeController(_ controller: MFMailComposeViewController,
                               didFinishWith result: MFMailComposeResult,
                               error: Error?) {
        switch result {
        case .sent:
            print("Email sent")
        case .saved:
            print("Draft saved")
        case .cancelled:
            print("Email cancelled")
        case  .failed:
            print("Email failed")
        }
        controller.dismiss(animated: true, completion: nil)
    }
}

我的控制台日志显示已发送电子邮件。

您是否确认您的 Constants 对象包含有效数据？也许你应该打印出来或者在它到达这里时在断点处查看它以确保它的内容没有问题。

此外，请确保您首先在设备上设置了有效的电子邮件帐户，以便为您发送电子邮件。如果它是一个开发设备，那么它可能已经被重置并在某个时候丢失了。

比较你的错误类型:

我的:

请注意 Error 的颜色发生了变化。这意味着它正在使用您定义的错误，该错误的范围是私有(private)的。您需要通过将错误重命名为其他名称来打破这一点。完成后，它应该可以解决您的错误。