WatchConnectivity transferFile的问题(观看-> iphone)

Question

我想使用WatchConnectivity和一个设置WCSession将在手表上创建的文件发送到iOS配套应用程序，但它无法连接到iPhone。当我使用发送包含字典的消息时，数据确实到达了iPhone。

AppDelegate和ExtensionDelegate都使用NotificationCenter与ViewController和ExtensionController通信。为了简单起见，它们被省略了，但通知工作得很好。

iOS的AppDelegate.swift

extension AppDelegate: WCSessionDelegate {
    // 1
    func sessionDidBecomeInactive(_ session: WCSession) {
        print("WC Session did become inactive")
    }

    // 2
    func sessionDidDeactivate(_ session: WCSession) {
        print("WC Session did deactivate")
        WCSession.default.activate()
    }

    // 3
    func session(_ session: WCSession, activationDidCompleteWith activationState: WCSessionActivationState, error: Error?) {
        if let error = error {
            print("WC Session activation failed with error: \(error.localizedDescription)")
            return
        }
        print("WC Session activated with state: \(activationState.rawValue)")
    }

    func setupWatchConnectivity() {
        // 1
        if WCSession.isSupported() {
            // 2
            let session = WCSession.default
            // 3
            session.delegate = self
            // 4
            session.activate()
        }
    }

    func session(_ session: WCSession, didFinish fileTransfer: WCSessionFileTransfer, error: Error?) {
        print("didFinish fileTransfer")
    }

    func session(_ session: WCSession, didReceive file: WCSessionFile) {
        print("didReceive file")
    }


    func session(_ session: WCSession, didReceiveMessage message: [String : Any], replyHandler: @escaping ([String : Any]) -> Void) { // 2
        print("didReceiveMessage reached")
    }
}

在我的手表上：

ExtensionDelegate.swift

extension ExtensionDelegate: WCSessionDelegate {

    func setupWatchConnectivity() {
        if WCSession.isSupported() {
            let session  = WCSession.default
            session.delegate = self
            session.activate()
        }
    }

    func session(_ session: WCSession, activationDidCompleteWith
        activationState: WCSessionActivationState, error: Error?) {
        if let error = error {
            print("WC Session activation failed with error: " +
                "\(error.localizedDescription)")
            return
        }
        print("WC Session activated with state: " +
            "\(activationState.rawValue)")
    }

    func sendFileToPhone(_ notification:Notification) {
        // 1
        if WCSession.isSupported() && WCSession.default.isReachable {
            // 2
            if let fileURL = notification.object as? URL {
                print("Sending file for URL: \(fileURL.absoluteURL.absoluteString)")
                WCSession.default.transferFile(fileURL, metadata: nil)  // <- if I use sendMessage here stuff works...
            }
        }
    }

    func session(_ session: WCSession, didFinish fileTransfer: WCSessionFileTransfer, error: Error?) {
        // handle filed transfer completion
        print("File transfer complete")
        print("Outstanding file transfers: \(WCSession.default.outstandingFileTransfers)")
        print("Has content pending: \(WCSession.default.hasContentPending)")
    }

    func session(_session: WCSession, didFinishFileTransfer fileTransfer: WCSessionFileTransfer, error: NSError?) {
        print("error: ", error as Any)
    }
}

在从Watch发送文件之后，如您所见，我检查了WCSession的outstandingFileTransfers和hasContentPending属性，它们表明文件应该已经被传输，但是我的AppDelegate扩展的:didReceive:方法没有被调用。同样，当我使用sendMessage时，会按预期调用AppDelegate的:didReceiveMessage:。

我遗漏了什么？

注意:我试过运行这个以不同通信方法为特色的Apple's demo project，我体验到了同样的事情: transferFile不会在对等物上触发任何东西。

Answer 1

这似乎是iOS 13/WatchOS6模拟器的一个错误。我曾尝试将Xcode模拟器更改为iOS 12和watchOS 5，这在this thread中是如何建议的，但问题消失了。