Ios 如何使用事件通道将数据从swift传输到FLIFT？

我正在制作一个应用程序，在这个应用程序中，我将数据从本机android和iOS端流到Flatter端，然后在UI中显示数据

我已经做了安卓部分。android部分将数据发送到Flatter端，并在UI中显示它们。但问题是如何为iOS swift端实现同样的目标

适用于我的Android代码：

new EventChannel(getFlutterView(), "Eventchannelname").setStreamHandler(
            new EventChannel.StreamHandler() {
                @Override
                public void onListen(Object args, EventChannel.EventSink events) {
                    Log.w(TAG, "adding listener");
                    mEventSink = events; // I use mEventsink.success(data) to pass the data to flutter side

                @Override
                public void onCancel(Object args) {
                    Log.w(TAG, "cancelling listener");
                }
            }
    );

如何在Swift本机代码中实现同样的功能。我在谷歌上搜索了一下，没有找到任何可以帮助我的东西

---

我希望swift和android java中的一样：我希望捕获局部变量中的事件，然后在需要将数据发送到Flatter的地方使用它

只需将mEventSink作为函数调用即可

mEventSink（数据）

使用Feventstream常量来表示流结束

mEventSink（Feventstream）

如果要将错误发送到颤振侧，请使用

mEventSink(FlutterError(code: "ERROR_CODE",
                             message: "Detailed message",
                             details: nil))

提及

完整的swift示例

let eventChannel = FlutterEventChannel(name: "your.channel.id", binaryMessenger: messenger!)                                                                            
        eventChannel.setStreamHandler(SwiftStreamHandler())      

.... 

class SwiftStreamHandler: NSObject, FlutterStreamHandler {                                                                                                                                  
    public func onListen(withArguments arguments: Any?, eventSink events: @escaping FlutterEventSink) -> FlutterError? {                                                                     
        events(true) // any generic type or more compex dictionary of [String:Any]
        events(FlutterError(code: "ERROR_CODE",
                             message: "Detailed message",
                             details: nil)) // in case of errors
        events(FlutterEndOfEventStream) // when stream is over
        return nil                                                                                                                                                                           
    }                                                                                                                                                                                        

    public func onCancel(withArguments arguments: Any?) -> FlutterError? {                                                                                                                   
        return nil                                                                                                                                                                           
    }                                                                                                                                                                                        
}               

---

我在官方的颤振回购协议中也发现了一个例子：

Swift中的代码如下所示：

import UIKit
import Flutter

enum ChannelName {
  static let battery = "samples.flutter.io/battery"
  static let charging = "samples.flutter.io/charging"
}

enum BatteryState {
  static let charging = "charging"
  static let discharging = "discharging"
}

enum MyFlutterErrorCode {
  static let unavailable = "UNAVAILABLE"
}

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate, FlutterStreamHandler {
  private var eventSink: FlutterEventSink?

  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    GeneratedPluginRegistrant.register(with: self)
    guard let controller = window?.rootViewController as? FlutterViewController else {
      fatalError("rootViewController is not type FlutterViewController")
    }
    let batteryChannel = FlutterMethodChannel(name: ChannelName.battery,
                                              binaryMessenger: controller.binaryMessenger)
    batteryChannel.setMethodCallHandler({
      [weak self] (call: FlutterMethodCall, result: FlutterResult) -> Void in
      guard call.method == "getBatteryLevel" else {
        result(FlutterMethodNotImplemented)
        return
      }
      self?.receiveBatteryLevel(result: result)
    })

    let chargingChannel = FlutterEventChannel(name: ChannelName.charging,
                                              binaryMessenger: controller.binaryMessenger)
    chargingChannel.setStreamHandler(self)
    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }

  private func receiveBatteryLevel(result: FlutterResult) {
    let device = UIDevice.current
    device.isBatteryMonitoringEnabled = true
    guard device.batteryState != .unknown  else {
      result(FlutterError(code: MyFlutterErrorCode.unavailable,
                          message: "Battery info unavailable",
                          details: nil))
      return
    }
    result(Int(device.batteryLevel * 100))
  }

  public func onListen(withArguments arguments: Any?,
                       eventSink: @escaping FlutterEventSink) -> FlutterError? {
    self.eventSink = eventSink
    UIDevice.current.isBatteryMonitoringEnabled = true
    sendBatteryStateEvent()
    NotificationCenter.default.addObserver(
      self,
      selector: #selector(AppDelegate.onBatteryStateDidChange),
      name: UIDevice.batteryStateDidChangeNotification,
      object: nil)
    return nil
  }

  @objc private func onBatteryStateDidChange(notification: NSNotification) {
    sendBatteryStateEvent()
  }

  private func sendBatteryStateEvent() {
    guard let eventSink = eventSink else {
      return
    }

    switch UIDevice.current.batteryState {
    case .full:
      eventSink(BatteryState.charging)
    case .charging:
      eventSink(BatteryState.charging)
    case .unplugged:
      eventSink(BatteryState.discharging)
    default:
      eventSink(FlutterError(code: MyFlutterErrorCode.unavailable,
                             message: "Charging status unavailable",
                             details: nil))
    }
  }

  public func onCancel(withArguments arguments: Any?) -> FlutterError? {
    NotificationCenter.default.removeObserver(self)
    eventSink = nil
    return nil
  }
}

---

我知道在java方面，我想用swift语言做同样的事情。我的答案是关于swift代码检查我提到的api参考。你能添加

messenger

的声明/实例化吗？有人让它工作吗？我被卡住了，流处理程序似乎没有发送数据