SwiftUI：发送电子邮件

Question

在正常的UIViewController中Swift，我用这个代码发邮件。[=13=]

let mailComposeViewController = configuredMailComposeViewController()

mailComposeViewController.navigationItem.leftBarButtonItem?.style = .plain
mailComposeViewController.navigationItem.rightBarButtonItem?.style = .plain
mailComposeViewController.navigationBar.tintColor = UIColor.white

if MFMailComposeViewController.canSendMail() {
    self.present(mailComposeViewController, animated: true, completion: nil)
} else {
    self.showSendMailErrorAlert()
}

如何在 SwiftUI 中实现同样的效果？

我需要使用 UIViewControllerRepresentable 吗？

Answer 1

如您所述，您需要通过 UIViewControllerRepresentable.

将组件移植到 SwiftUI

这是一个简单的实现：

struct MailView: UIViewControllerRepresentable {

    @Binding var isShowing: Bool
    @Binding var result: Result<MFMailComposeResult, Error>?

    class Coordinator: NSObject, MFMailComposeViewControllerDelegate {

        @Binding var isShowing: Bool
        @Binding var result: Result<MFMailComposeResult, Error>?

        init(isShowing: Binding<Bool>,
             result: Binding<Result<MFMailComposeResult, Error>?>) {
            _isShowing = isShowing
            _result = result
        }

        func mailComposeController(_ controller: MFMailComposeViewController,
                                   didFinishWith result: MFMailComposeResult,
                                   error: Error?) {
            defer {
                isShowing = false
            }
            guard error == nil else {
                self.result = .failure(error!)
                return
            }
            self.result = .success(result)
        }
    }

    func makeCoordinator() -> Coordinator {
        return Coordinator(isShowing: $isShowing,
                           result: $result)
    }

    func makeUIViewController(context: UIViewControllerRepresentableContext<MailView>) -> MFMailComposeViewController {
        let vc = MFMailComposeViewController()
        vc.mailComposeDelegate = context.coordinator
        return vc
    }

    func updateUIViewController(_ uiViewController: MFMailComposeViewController,
                                context: UIViewControllerRepresentableContext<MailView>) {

    }
}

用法:

struct ContentView: View {

    @State var result: Result<MFMailComposeResult, Error>? = nil
    @State var isShowingMailView = false

    var body: some View {

        VStack {
            if MFMailComposeViewController.canSendMail() {
                Button("Show mail view") {
                    self.isShowingMailView.toggle()
                }
            } else {
                Text("Can't send emails from this device")
            }
            if result != nil {
                Text("Result: \(String(describing: result))")
                    .lineLimit(nil)
            }
        }
        .sheet(isPresented: $isShowingMailView) {
            MailView(isShowing: self.$isShowingMailView, result: self.$result)
        }

    }

}

（在 iPhone 7 Plus 运行 iOS 13 上测试 - 非常有效）

更新为 Xcode11.4

Answer 2

@Matteo 的回答很好但是需要使用presentation 环境变量。我在这里更新了它，它解决了评论中的所有问题。

import SwiftUI
import UIKit
import MessageUI

struct MailView: UIViewControllerRepresentable {

    @Environment(\.presentationMode) var presentation
    @Binding var result: Result<MFMailComposeResult, Error>?

    class Coordinator: NSObject, MFMailComposeViewControllerDelegate {

        @Binding var presentation: PresentationMode
        @Binding var result: Result<MFMailComposeResult, Error>?

        init(presentation: Binding<PresentationMode>,
             result: Binding<Result<MFMailComposeResult, Error>?>) {
            _presentation = presentation
            _result = result
        }

        func mailComposeController(_ controller: MFMailComposeViewController,
                                   didFinishWith result: MFMailComposeResult,
                                   error: Error?) {
            defer {
                $presentation.wrappedValue.dismiss()
            }
            guard error == nil else {
                self.result = .failure(error!)
                return
            }
            self.result = .success(result)
        }
    }

    func makeCoordinator() -> Coordinator {
        return Coordinator(presentation: presentation,
                           result: $result)
    }

    func makeUIViewController(context: UIViewControllerRepresentableContext<MailView>) -> MFMailComposeViewController {
        let vc = MFMailComposeViewController()
        vc.mailComposeDelegate = context.coordinator
        return vc
    }

    func updateUIViewController(_ uiViewController: MFMailComposeViewController,
                                context: UIViewControllerRepresentableContext<MailView>) {

    }
}

用法：

import SwiftUI
import MessageUI

struct ContentView: View {

   @State var result: Result<MFMailComposeResult, Error>? = nil
   @State var isShowingMailView = false

    var body: some View {
        Button(action: {
            self.isShowingMailView.toggle()
        }) {
            Text("Tap Me")
        }
        .disabled(!MFMailComposeViewController.canSendMail())
        .sheet(isPresented: $isShowingMailView) {
            MailView(result: self.$result)
        }
    }
}

struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

Answer 3

答案正确 Hobbes the Tige & Matteo

根据评论，如果您需要在按钮或点击手势上未设置电子邮件时显示警报

@State var isShowingMailView = false
@State var alertNoMail = false
@State var result: Result<MFMailComposeResult, Error>? = nil

HStack {
                Image(systemName: "envelope.circle").imageScale(.large)
                Text("Contact")
            }.onTapGesture {
                MFMailComposeViewController.canSendMail() ? self.isShowingMailView.toggle() : self.alertNoMail.toggle()
            }
                //            .disabled(!MFMailComposeViewController.canSendMail())
                .sheet(isPresented: $isShowingMailView) {
                    MailView(result: self.$result)
            }
            .alert(isPresented: self.$alertNoMail) {
                Alert(title: Text("NO MAIL SETUP"))
            }

预填充收件人，正文...我还添加了系统声音，与苹果电子邮件发送声音相同

参数：recipients & messageBody 可以在初始化时注入。邮件查看器

import AVFoundation
import Foundation
import MessageUI
import SwiftUI
import UIKit

struct MailView: UIViewControllerRepresentable {
    @Environment(\.presentationMode) var presentation
    @Binding var result: Result<MFMailComposeResult, Error>?
    var recipients = [String]()
    var messageBody = ""

    class Coordinator: NSObject, MFMailComposeViewControllerDelegate {
        @Binding var presentation: PresentationMode
        @Binding var result: Result<MFMailComposeResult, Error>?

        init(presentation: Binding<PresentationMode>,
             result: Binding<Result<MFMailComposeResult, Error>?>)
        {
            _presentation = presentation
            _result = result
        }

        func mailComposeController(_: MFMailComposeViewController,
                                   didFinishWith result: MFMailComposeResult,
                                   error: Error?)
        {
            defer {
                $presentation.wrappedValue.dismiss()
            }
            guard error == nil else {
                self.result = .failure(error!)
                return
            }
            self.result = .success(result)
            
            if result == .sent {
            AudioServicesPlayAlertSound(SystemSoundID(1001))
            }
        }
    }

    func makeCoordinator() -> Coordinator {
        return Coordinator(presentation: presentation,
                           result: $result)
    }

    func makeUIViewController(context: UIViewControllerRepresentableContext<MailView>) -> MFMailComposeViewController {
        let vc = MFMailComposeViewController()
        vc.setToRecipients(recipients)
        vc.setMessageBody(messageBody, isHTML: true)
        vc.mailComposeDelegate = context.coordinator
        return vc
    }

    func updateUIViewController(_: MFMailComposeViewController,
                                context _: UIViewControllerRepresentableContext<MailView>) {}
}

Answer 4

我已经为它创建了一个 github repository。只需将它添加到您的项目中并像这样使用它：

struct ContentView: View {

@State var showMailSheet = false

var body: some View {
    NavigationView {
        Button(action: {
            self.showMailSheet.toggle()
        }) {
            Text("compose")
        }
    }
    .sheet(isPresented: self.$showMailSheet) {
        MailView(isShowing: self.$showMailSheet,
                 resultHandler: {
                    value in
                    switch value {
                    case .success(let result):
                        switch result {
                        case .cancelled:
                            print("cancelled")
                        case .failed:
                            print("failed")
                        case .saved:
                            print("saved")
                        default:
                            print("sent")
                        }
                    case .failure(let error):
                        print("error: \(error.localizedDescription)")
                    }
        },
                 subject: "test Subjet",
                 toRecipients: ["recipient@test.com"],
                 ccRecipients: ["cc@test.com"],
                 bccRecipients: ["bcc@test.com"],
                 messageBody: "works like a charm!",
                 isHtml: false)
        .safe()
        
    }

  }
}

safe() 修饰符检查 MFMailComposeViewController.canSendMail() 是否为 false，它会自动消除模态并尝试打开 mailto link.

Answer 5

好吧，我有一个旧代码，我用这种方式在 SwiftUI 中使用。属于这个class的静态函数基本都在我的Utilities.swift文件里。但出于演示目的，我将其移至此处。

同时为了保留委托并正常工作，我将其用作单例模式。

第 1 步：创建电子邮件助手class

import Foundation
import MessageUI

class EmailHelper: NSObject, MFMailComposeViewControllerDelegate {
    public static let shared = EmailHelper()
    private override init() {
        //
    }
    
    func sendEmail(subject:String, body:String, to:String){
        if !MFMailComposeViewController.canSendMail() {
            // Utilities.showErrorBanner(title: "No mail account found", subtitle: "Please setup a mail account")
            return //EXIT
        }
        
        let picker = MFMailComposeViewController()
        
        picker.setSubject(subject)
        picker.setMessageBody(body, isHTML: true)
        picker.setToRecipients([to])
        picker.mailComposeDelegate = self
        
        EmailHelper.getRootViewController()?.present(picker, animated: true, completion: nil)
    }
    
    func mailComposeController(_ controller: MFMailComposeViewController, didFinishWith result: MFMailComposeResult, error: Error?) {
        EmailHelper.getRootViewController()?.dismiss(animated: true, completion: nil)
    }
    
    static func getRootViewController() -> UIViewController? {
        (UIApplication.shared.connectedScenes.first?.delegate as? SceneDelegate)?.window?.rootViewController

         // OR If you use SwiftUI 2.0 based WindowGroup try this one
         // UIApplication.shared.windows.first?.rootViewController
    }
}

第二步：在SwiftUI中这样调用即可class

Button(action: {
   EmailHelper.shared.sendEmail(subject: "Anything...", body: "", to: "")
 }) {
     Text("Send Email")
 }

我在基于 SwiftUI 的项目中使用它。

Answer 6

Yeeee @Hobbes Tige 的回答很好但是...

让我们做得更好！如果用户没有 邮件应用程序 怎么办（就像我没有）。您可以通过尝试其他邮件应用来处理它。

if MFMailComposeViewController.canSendMail() {
   self.showMailView.toggle()
} else if let emailUrl = Utils.createEmailUrl(subject: "Yo, sup?", body: "hot dog") {
   UIApplication.shared.open(emailUrl)
} else {
   self.alertNoMail.toggle()
}

createEmailUrl

static func createEmailUrl(subject: String, body: String) -> URL? {
        let to = YOUR_EMAIL
        let subjectEncoded = subject.addingPercentEncoding(withAllowedCharacters: .urlHostAllowed)!
        let bodyEncoded = body.addingPercentEncoding(withAllowedCharacters: .urlHostAllowed)!

        let gmailUrl = URL(string: "googlegmail://co?to=\(to)&subject=\(subjectEncoded)&body=\(bodyEncoded)")
        let outlookUrl = URL(string: "ms-outlook://compose?to=\(to)&subject=\(subjectEncoded)")
        let yahooMail = URL(string: "ymail://mail/compose?to=\(to)&subject=\(subjectEncoded)&body=\(bodyEncoded)")
        let sparkUrl = URL(string: "readdle-spark://compose?recipient=\(to)&subject=\(subjectEncoded)&body=\(bodyEncoded)")
        let defaultUrl = URL(string: "mailto:\(to)?subject=\(subjectEncoded)&body=\(bodyEncoded)")

        if let gmailUrl = gmailUrl, UIApplication.shared.canOpenURL(gmailUrl) {
            return gmailUrl
        } else if let outlookUrl = outlookUrl, UIApplication.shared.canOpenURL(outlookUrl) {
            return outlookUrl
        } else if let yahooMail = yahooMail, UIApplication.shared.canOpenURL(yahooMail) {
            return yahooMail
        } else if let sparkUrl = sparkUrl, UIApplication.shared.canOpenURL(sparkUrl) {
            return sparkUrl
        }

        return defaultUrl
    }

Info.plist

<key>LSApplicationQueriesSchemes</key>
<array>
    <string>googlegmail</string>
    <string>ms-outlook</string>
    <string>readdle-spark</string>
    <string>ymail</string>
</array>

Answer 7

我还改进了@Hobbes 的回答，以便轻松配置主题、收件人等参数。

Checkout this gist

连要点都懒得看，那SPM呢？

您现在可以在不同的项目中轻松复制粘贴此礼物。

用法；

import SwiftUI
import MessagesUI
// import SwiftUIEKtensions // via SPM

@State private var result: Result<MFMailComposeResult, Error>? = nil
@State private var isShowingMailView = false

var body: some View {
    Form {
        Button(action: {
            if MFMailComposeViewController.canSendMail() {
                self.isShowingMailView.toggle()
            } else {
                print("Can't send emails from this device")
            }
            if result != nil {
                print("Result: \(String(describing: result))")
            }
        }) {
            HStack {
                Image(systemName: "envelope")
                Text("Contact Us")
            }
        }
        // .disabled(!MFMailComposeViewController.canSendMail())
    }
    .sheet(isPresented: $isShowingMailView) {
        MailView(result: $result) { composer in
            composer.setSubject("Secret")
            composer.setToRecipients(["fancy@mail.com"])
        }
    }
}

Answer 8

我升级并简化了@Mahmud Assan 对新 SwiftUI 生命周期 的回答。

import Foundation
import MessageUI

class EmailService: NSObject, MFMailComposeViewControllerDelegate {
public static let shared = EmailService()

func sendEmail(subject:String, body:String, to:String, completion: @escaping (Bool) -> Void){
 if MFMailComposeViewController.canSendMail(){
    let picker = MFMailComposeViewController()
    picker.setSubject(subject)
    picker.setMessageBody(body, isHTML: true)
    picker.setToRecipients([to])
    picker.mailComposeDelegate = self
    
   UIApplication.shared.windows.first?.rootViewController?.present(picker,  animated: true, completion: nil)
}
  completion(MFMailComposeViewController.canSendMail())
}

func mailComposeController(_ controller: MFMailComposeViewController, didFinishWith result: MFMailComposeResult, error: Error?) {
    controller.dismiss(animated: true, completion: nil)
     }
}

用法：

Button(action: {
            EmailService.shared.sendEmail(subject: "hello", body: "this is body", to: "asd@gmail.com") { (isWorked) in
                if !isWorked{ //if mail couldn't be presented
                    // do action
                }
            }
        }, label: {
            Text("Send Email")
        })

Answer 9

不幸的是，@Matteo 的解决方案对我来说并不完美。它看起来有问题:(

备选方案

struct MailComposeSheet<T: View>: UIViewControllerRepresentable {
    let view: T

    @Binding var isPresented: Bool

    func makeUIViewController(context: Context) -> UIHostingController<T> {
        UIHostingController(rootView: view)
    }

    func updateUIViewController(_ uiViewController: UIHostingController<T>, context: Context) {
        uiViewController.rootView = view

        if isPresented, uiViewController.presentedViewController == nil {
            let picker = MFMailComposeViewController()

            picker.mailComposeDelegate = context.coordinator
            picker.presentationController?.delegate = context.coordinator

            uiViewController.present(picker, animated: true)
        }
    }

    func makeCoordinator() -> Coordinator {
        Coordinator(self)
    }

    class Coordinator: NSObject, MFMailComposeViewControllerDelegate, UIAdaptivePresentationControllerDelegate {
        var parent: MailComposeSheet

        init(_ mailComposeSheet: MailComposeSheet) {
            self.parent = mailComposeSheet
        }

        func mailComposeController(_ controller: MFMailComposeViewController, didFinishWith result: MFMailComposeResult, error: Error?) {
            controller.dismiss(animated: true) { [weak self] in
                self?.parent.isPresented = false
            }
        }

        func presentationControllerDidDismiss(_ presentationController: UIPresentationController) {
            parent.isPresented = false
        }
    }
}

extension View {
    func mailComposeSheet(isPresented: Binding<Bool>) -> some View {
        MailComposeSheet(
            view: self,
            isPresented: isPresented
        )
    }
}

用法：

struct ContentView: View {
    @State var showEmailComposer = false

    var body: some View {
        Button("Tap me") {
            showEmailComposer = true
        }
        .mailComposeSheet(isPresented: $showEmailComposer)
    }
}

我是 Swift 的新手，如果我做错了什么请告诉我。

Answer 10

在 iOS 14 之前，iOS 上的默认电子邮件应用程序是 Mail。当然，您可以安装其他电子邮件应用程序

   if MFMailComposeViewController.canSendMail() {
    let mailController = MFMailComposeViewController(rootViewController: self)
    mailController.setSubject("Test")
    mailController.setToRecipients(["mail@test.com"])
    mailController.mailComposeDelegate = self
    present(mailController, animated: true, completion: nil)
}

今天作为开发人员，我想尊重用户对电子邮件应用程序的选择，无论是 Mail、Edison、Gmail、Outlook 还是 Hey。为此，我无法使用 MFMailComposeViewController。相反，我必须将 mailto 添加到 LSApplicationQueriesSchemes Info.plist 中的键，然后，当用户想要发送电子邮件时，使用此代码：

if UIApplication.shared.canOpenURL(url) {
    UIApplication.shared.open(url, options: [.universalLinksOnly : false]) { (success) in
        // Handle success/failure
    }
}

与 MFMailComposeViewController 不同，此方法将用户发送到他们选择的电子邮件应用程序，同时关闭源应用程序。不理想。

Answer 11

我认为不需要绑定 isPresented 或结果，因此我建议的解决方案是在调用 MFMailComposeViewControllerDelegate 时使用回调。这也使得结果不可为空。

import Foundation
import MessageUI
import SwiftUI
import UIKit

public struct MailView: UIViewControllerRepresentable {
    public struct Attachment {
        public let data: Data
        public let mimeType: String
        public let filename: String

        public init(data: Data, mimeType: String, filename: String) {
            self.data = data
            self.mimeType = mimeType
            self.filename = filename
        }
    }

    public let onResult: ((Result<MFMailComposeResult, Error>) -> Void)

    public let subject: String?
    public let message: String?
    public let attachment: Attachment?

    public class Coordinator: NSObject, MFMailComposeViewControllerDelegate {
        public var onResult: ((Result<MFMailComposeResult, Error>) -> Void)

        init(onResult: @escaping ((Result<MFMailComposeResult, Error>) -> Void)) {
            self.onResult = onResult
        }

        public func mailComposeController(
            _ controller: MFMailComposeViewController,
            didFinishWith result: MFMailComposeResult,
            error: Error?
        ) {
            if let error = error {
                self.onResult(.failure(error))
            } else {
                self.onResult(.success(result))
            }
        }
    }

    public init(
        subject: String? = nil,
        message: String? = nil,
        attachment: MailView.Attachment? = nil,
        onResult: @escaping ((Result<MFMailComposeResult, Error>) -> Void)
    ) {
        self.subject = subject
        self.message = message
        self.attachment = attachment
        self.onResult = onResult
    }

    public func makeCoordinator() -> Coordinator {
        Coordinator(onResult: onResult)
    }

    public func makeUIViewController(
        context: UIViewControllerRepresentableContext<MailView>
    ) -> MFMailComposeViewController {
        let controller = MFMailComposeViewController()
        controller.mailComposeDelegate = context.coordinator
        if let subject = subject {
            controller.setSubject(subject)
        }
        if let message = message {
            controller.setMessageBody(message, isHTML: false)
        }
        if let attachment = attachment {
            controller.addAttachmentData(
                attachment.data,
                mimeType: attachment.mimeType,
                fileName: attachment.filename
            )
        }
        return controller
    }

    public func updateUIViewController(
        _ uiViewController: MFMailComposeViewController,
        context: UIViewControllerRepresentableContext<MailView>
    ) {
        // nothing to do here
    }
}

用法

struct ContentView: View {
    @State var showEmailComposer = false

    var body: some View {
        Button("Tap me") {
            showEmailComposer = true
        }
        .sheet(isPresented: $showEmailComposer) {
            MailView(
                subject: "Email subject",
                message: "Message",
                attachment: nil,
                onResult: { _ in
                     // Handle the result if needed.
                     self.showEmailComposer = false
                }
            )
        }
    }
}

Answer 12

对于像我这样的人来说，想要一个更好的解决方案而不会使用户的屏幕出现故障，我在这个来自 Medium 的 post 中找到了一个非常好的解决方案。该解决方案类似于@Mahmud Assan 的回答，但有更多的电子邮件应用程序选项和错误的应用程序警报。

我替换了一些方法代码以允许打开更多电子邮件应用程序，而不仅仅是 Mail 或 gmail。

首先，记得在Info.plist中添加相应的信息，在我的例子中：

<key>LSApplicationQueriesSchemes</key>
<array>
    <string>googlegmail</string>
    <string>ms-outlook</string>
    <string>readdle-spark</string>
    <string>ymail</string>
</array>

之后您需要使用以下代码创建一个新的 swift 文件：

import SwiftUI
import MessageUI

class EmailHelper: NSObject {
    /// singleton
    static let shared = EmailHelper()
    private override init() {}
}

extension EmailHelper {
    
    func send(subject: String, body: String, to: [String]) {
        
        let scenes = UIApplication.shared.connectedScenes
        let windowScene = scenes.first as? UIWindowScene
        
        guard let viewController = windowScene?.windows.first?.rootViewController else {
            return
        }
        
        if !MFMailComposeViewController.canSendMail() {
            let subjectEncoded = subject.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)!
            let bodyEncoded = body.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)!
            let mails = to.joined(separator: ",")
            
            let alert = UIAlertController(title: "Cannot open Mail!", message: "", preferredStyle: .actionSheet)
            
            var haveExternalMailbox = false
            
            if let url = createEmailUrl(to: mails, subject: subjectEncoded, body: bodyEncoded), UIApplication.shared.canOpenURL(url) {
                haveExternalMailbox = true
                alert.addAction(UIAlertAction(title: "Gmail", style: .default, handler: { (action) in
                    UIApplication.shared.open(url)
                }))
            }
            
            if haveExternalMailbox {
                alert.message = "Would you like to open an external mailbox?"
            } else {
                alert.message = "Please add your mail to Settings before using the mail service."
                
                if let settingsUrl = URL(string: UIApplication.openSettingsURLString),
                   UIApplication.shared.canOpenURL(settingsUrl) {
                    alert.addAction(UIAlertAction(title: "Open Settings App", style: .default, handler: { (action) in
                        UIApplication.shared.open(settingsUrl)
                    }))
                }
            }
            
            alert.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: nil))
            viewController.present(alert, animated: true, completion: nil)
            return
        }
        
        let mailCompose = MFMailComposeViewController()
        mailCompose.setSubject(subject)
        mailCompose.setMessageBody(body, isHTML: false)
        mailCompose.setToRecipients(to)
        mailCompose.mailComposeDelegate = self
        
        viewController.present(mailCompose, animated: true, completion: nil)
    }
    
    private func createEmailUrl(to: String, subject: String, body: String) -> URL? {
        let subjectEncoded = subject.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)!
        let bodyEncoded = body.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)!
        
        let gmailUrl = URL(string: "googlegmail://co?to=\(to)&subject=\(subjectEncoded)&body=\(bodyEncoded)")
        let outlookUrl = URL(string: "ms-outlook://compose?to=\(to)&subject=\(subjectEncoded)")
        let yahooMail = URL(string: "ymail://mail/compose?to=\(to)&subject=\(subjectEncoded)&body=\(bodyEncoded)")
        let sparkUrl = URL(string: "readdle-spark://compose?recipient=\(to)&subject=\(subjectEncoded)&body=\(bodyEncoded)")
        let defaultUrl = URL(string: "mailto:\(to)?subject=\(subjectEncoded)&body=\(bodyEncoded)")
        
        if let gmailUrl = gmailUrl, UIApplication.shared.canOpenURL(gmailUrl) {
            return gmailUrl
        } else if let outlookUrl = outlookUrl, UIApplication.shared.canOpenURL(outlookUrl) {
            return outlookUrl
        } else if let yahooMail = yahooMail, UIApplication.shared.canOpenURL(yahooMail) {
            return yahooMail
        } else if let sparkUrl = sparkUrl, UIApplication.shared.canOpenURL(sparkUrl) {
            return sparkUrl
        }
        
        return defaultUrl
    }
    
}

// MARK: - MFMailComposeViewControllerDelegate
extension EmailHelper: MFMailComposeViewControllerDelegate {
    
    func mailComposeController(_ controller: MFMailComposeViewController, didFinishWith result: MFMailComposeResult, error: Error?) {
        controller.dismiss(animated: true, completion: nil)
    }
}

现在，转到您要实现此功能的视图：

  struct OpenMailView: View {
    var body: some View {
        Button("Send email") {
            EmailHelper.shared.send(subject: "Help", body: "", to: ["email@gmail.com"])
        }
    }
}

SwiftUI：发送电子邮件

SwiftUI: Send email

messageui

swift

mfmailcomposeviewcontroller

swiftui