SwiftUI : envoyer un e-mail

Question

Dans un UIViewController normal dans Swift, j'utilise ce code pour envoyer un mail.

 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()
}

Comment puis-je obtenir la même chose dans SwiftUI ?

Dois-je utiliser UIViewControllerRepresentable ?

Answer 1

La réponse de @Matteo est bonne mais elle doit utiliser la variable d'environnement de présentation. Je l'ai mis à jour ici et il répond à toutes les préoccupations dans les commentaires.

 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>) {

    }
}

Usage:

 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 2

Comme vous l'avez mentionné, vous devez porter le composant sur SwiftUI via UIViewControllerRepresentable .

Voici une implémentation simple :

 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>) {

    }
}

---

Utilisation :

 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)
        }

    }

}

---

(Testé sur iPhone 7 Plus sous iOS 13 - fonctionne comme un charme)

Mise à jour pour Xcode 11.4

Answer 3

Les réponses sont correctes Hobbes le Tige & Matteo

À partir des commentaires, si vous devez afficher une alerte si aucun e-mail n'est configuré sur le bouton ou appuyez sur le geste

 @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"))
            }

Pour pré-remplir To, Body ... j'ajoute également le son du système comme le son d'envoi d'e-mails Apple

Paramètres : les destinataires et le messageBody peuvent être injectés lors de l'initialisation. CourrierVoir

 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>) {}
}