Flutter开发之——IOS通信MethodChannel

在Flutter中，MethodChannel是一种在宿主(iOS)和平台(Android)之间进行异步通信的方式。以下是一个使用MethodChannel的示例：

首先，在iOS端创建一个方法，并通过FlutterMethodChannel将其暴露给Flutter端。

import Flutter
import UIKit
 
@UIApplicationMain
class AppDelegate: FlutterAppDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
    GeneratedPluginRegistrant.register(with: self)
    let controller : FlutterViewController = window?.rootViewController as! FlutterViewController
    let chanel = FlutterMethodChannel(name: "samples.flutter.dev/battery", binaryMessenger: controller)
    chanel.setMethodCallHandler({ (call: FlutterMethodCall, result: @escaping FlutterResult) -> Void in
        // Handle battery level queries here
        if ("getBatteryLevel" == call.method) {
            self.getBatteries(result: result)
        } else {
            result(FlutterMethodNotImplemented)
        }
    })
    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }
  
  private func getBatteries(result: FlutterResult) {
    // Implementation of getting battery level
    let batteryLevel = "50" // Example
    result(batteryLevel)
  }
}

然后，在Flutter端，你需要创建一个MethodChannel并调用iOS端暴露的方法。

import 'package:flutter/services.dart';
 
class BatteryLevel {
  static const MethodChannel _channel =
      const MethodChannel('samples.flutter.dev/battery');
 
  static Future<String> get batteryLevel async {
    final String batteryLevel = await _channel.invokeMethod('getBatteryLevel');
    return batteryLevel;
  }
}

在这个例子中，我们创建了一个名为"getBatteryLevel"的方法，在iOS端我们通过这个方法获取电池电量信息，并返回给Flutter端。这样，Flutter端可以获取并展示电池电量信息。