platform channels主要用來客戶端和宿主app之間消息的傳遞薪捍，異步的形式進(jìn)行傳遞
調(diào)用過程

1. Flutter客戶端發(fā)送消息
2. 原生平臺(tái)接受并返回結(jié)果（iOS響應(yīng)方法:FlutterMethodChannel）(android響應(yīng)方法:MethodChannel)

具體操作

第一步：Flutter中配置代碼觸發(fā)和接受消息

• MethodChannel配置的參數(shù)是唯一的，一般命名規(guī)范如下：域名/功能名稱
• 使用invokeMethod("方法名稱")觸發(fā)方法

class _TestNativeConnectState extends State<TestNativeConnect> {
  // 命名規(guī)則：域名/功能（要唯一 ）
  static const platform1 = const MethodChannel("cy.com/getMessate");
  String _nativeMessate = "null";
  @override
  Widget build(BuildContext context) {
    return Center(
      child: Column(
        children: [
          Text("獲取原生傳遞數(shù)據(jù):${_nativeMessate}"),
          RaisedButton(
            child: Text("向原生獲取數(shù)據(jù)"),
            onPressed: getDataFromNative,
          )
        ],
      ),
    );
  }
  Future<void> getDataFromNative() async {
    final result = await platform1.invokeMethod("getDataFromNative");//挑起方法
    setState(() {
      _nativeMessate = result;
    });
  }
}

OC代碼：

FlutterViewController *controller = (FlutterViewController*)self.window.rootViewController;
FlutterMethodChannel *channel = [FlutterMethodChannel methodChannelWithName:@"cy.come/getMessate" binaryMessenger:controller.binaryMessenger];

__weak typeof(self) weakSelf = self;
[channel setMethodCallHandler:^(FlutterMethodCall *call,FlutterResult result){
    if([@"getDataFromNative" isequalToString:call.method]){
        //result([FlutterError errorWithCode:@"5000",message:"錯(cuò)誤信息",details:nil]);
        result(@"iOS - OC");
    }
    else{
        result(FlutterMethodNotImplemented);
    }
}];

第二步：iOS中響應(yīng)并傳遞消息

// 獲取Flutter ViewController
    let controller : FlutterViewController = window.rootViewController! as! FlutterViewController
    // 創(chuàng)建FlutterMethodChannel
    // 參數(shù)一：與flutter中設(shè)置的MethodChannel標(biāo)識(shí)對(duì)齊  參數(shù)二：二進(jìn)制消息
    let channel = FlutterMethodChannel(name: "cy.com/getMessate", binaryMessenger: controller.binaryMessenger)
    // 監(jiān)聽channel調(diào)用方法
    channel.setMethodCallHandler { (call:FlutterMethodCall, result:@escaping FlutterResult) in
        guard call.method == "getDataFromNative" else{//判斷方法是否實(shí)現(xiàn)
            result(FlutterMethodNotImplemented);//返回當(dāng)前方法未實(shí)現(xiàn)
            return
        }
        // 返回錯(cuò)誤信息
//        result(FlutterError(code: "5000", message: "消息不存在", details: nil))
        result("iOS")
    }

第三步：Android中響應(yīng)并傳遞消息

    override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
        super.configureFlutterEngine(flutterEngine)
        // 創(chuàng)建methodchannel
        val methodChannel = MethodChannel(flutterEngine.dartExecutor.binaryMessenger,"cy.com/getMessate");
        // 添加回調(diào)
        methodChannel.setMethodCallHandler{
            call, result ->
            if (call.method == "getDataFromNative"){
                result.success("android")
                result.error("5000","拋出異常",null)
            }else{
                result.notImplemented()
            }
        }
    }