Flutter开发之——IOS通信BasicMessageChannel

在Flutter中，BasicMessageChannel是一个用于跨平台通信的类。它可以在平台（如iOS）和Dart代码之间发送字符串或者JSON消息。

以下是一个在iOS（Swift）和Flutter（Dart）之间使用BasicMessageChannel的例子：

首先，在iOS（Swift）中，你需要这样设置一个BasicMessageChannel并添加一个处理方法：

import Flutter
import UIKit
 
@UIApplicationMain
class AppDelegate: FlutterAppDelegate {
  lazy var basicMessageChannel: FlutterBasicMessageChannel = {
    return FlutterBasicMessageChannel(name: "samples.flutter.dev/battery",
                                      binaryMessenger: self.binaryMessenger,
                                      codec: FlutterJSONMessageCodec.sharedInstance())
  }()
 
  override func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
    basicMessageChannel.setMessageHandler({(message: Any?, reply: FlutterReply?) -> Void in
      if let message = message as? Dictionary<String, Any>,
        let status = message["status"] as? String {
        if status == "getBatteryLevel" {
          self.getBatteryLevel(reply: reply)
        }
      }
    })
    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }
 
  private func getBatteryLevel(reply: FlutterReply?) {
    // 假设获取电池电量的逻辑
    let batteryLevel = 80
    reply?(["status": "OK", "batteryLevel": batteryLevel])
  }
}

然后，在Flutter（Dart）中，你需要这样设置一个BasicMessageChannel并发送消息：

import 'package:flutter/services.dart';
 
class BatteryLevel {
  static const MethodChannel _channel =
      const MethodChannel('samples.flutter.dev/battery');
 
  static Future<String> get batteryLevel async {
    final Map<String, String> batteryLevel =
        await _channel.invokeMapMethod<String, String>('getBatteryLevel');
    return batteryLevel?['status'];
  }
}
 
void main() {
  runApp(MyApp());
}
 
class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('Battery Level'),
        ),
        body: Center(
          child: FutureBuilder<String>(
            future: BatteryLevel.batteryLevel,
            builder: (context, snapshot) {