问题

所以，当我尝试为我的Flutter项目实现平台方法通道时，我遇到了一个问题。当我尝试从Flutter调用iOS端的方法时，它被触发并一切都运行完美，但是当我尝试从iOS端（AppDelegate文件）调用一个方法以执行特定任务时，它不起作用。

AppDelegate.swift 代码:

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate {
    
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
    FirebaseApp.configure()
    application.registerForRemoteNotifications()
    GeneratedPluginRegistrant.register(with: self)

    let controller = (window?.rootViewController as! FlutterViewController)
    let methodChannle = FlutterMethodChannel(name: "channelMethodTest", binaryMessenger: controller.binaryMessenger)
    methodChannle.invokeMethod("taskName", arguments: [:])
    
    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }

Flutter main.dart:

const methodChannel = MethodChannel('channelMethodTest');

Future<void> methodHandler(MethodCall call) async {
  final String idea = call.arguments;

  switch (call.method) {
    case "taskName":
      print("从iOS到Flutter接收任务");
      break;
    default:
      print('对于方法 ${call.method} 没有方法处理程序');
  }
}

Future<void> main() async {
  WidgetsFlutterBinding.ensureInitialized();
  methodChannel.setMethodCallHandler(methodHandler);
}

我尝试搜索了一些教程，但是没有找到适合的解决方法。

<details>
<summary>英文:</summary>

so i have an issue when trying to implement the platform method channel for my flutter project, When i try to invoke a method from flutter to ios side, it gets triggered and everything is working perfectly but when i try to invoke a method from ios side (appDelegate file) to flutter in order to perform a sepecific task, it&#39;s not working.

AppDelegate.swift Code:

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate {

override func application(
_ application: UIApplication,
didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
) -> Bool {
FirebaseApp.configure()
application.registerForRemoteNotifications()
GeneratedPluginRegistrant.register(with: self)

let controller = (window?.rootViewController as! FlutterViewController)
    let methodChannle = FlutterMethodChannel(name: "channelMethodTest", binaryMessenger: controller.binaryMessenger)
    methodChannle.invokeMethod("taskName", arguments: [:])
  

return super.application(application, didFinishLaunchingWithOptions: launchOptions)

}

Flutter main.dart:

const methodChannel = MethodChannel('channelMethodTest');

Future<void> methodHandler(MethodCall call) async {
final String idea = call.arguments;

switch (call.method) {
case "taskName":
print(
"receiving task from ios to flutter");
break;
default:
print('no method handler for method ${call.method}');
}
}

Future<void> main() async {
WidgetsFlutterBinding.ensureInitialized();
methodChannel.setMethodCallHandler(methodHandler);
}

I tried searching for tutos on how to do it but i cannot find any

</details>


# 答案1
**得分**: 0

让渠道名称在Flutter和iOS端保持相同。现在它们似乎是不同的：

```Dart
let methodChannle = FlutterMethodChannel(name: "channelMethodTest", binaryMessenger: controller.binaryMessenger)

const methodChannel = MethodChannel('beyang.com-channelMethodTest');

let methodChannle = FlutterMethodChannel(name: "channelMethodTest", binaryMessenger: controller.binaryMessenger)

const methodChannel = MethodChannel('beyang.com-channelMethodTest');

答案2

得分: 0

需要将channelmethod变量设为全局变量，然后需要在didFinishLaunchingWithOptions函数中实例化方法通道(method channel)，如果你要使用方法通道(method channel)来调用应用程序代理(app delegate)或与之相关的任何扩展(extension)中的方法。