Flutter平台对象通信插件platform_object_channel的使用

Flutter平台对象通信插件platform_object_channel的使用

platform_object_channel 是一个用于在平台对象实例和 Dart 对象实例之间创建通道的 Flutter 插件。

支持情况

使用方法

要使用此插件，你需要在 pubspec.yaml 文件中添加 platform_object_channel 作为依赖项：

dependencies:
  platform_object_channel: ^版本号

示例

Dart 示例

import 'dart:async';

import 'package:flutter/material.dart';
import 'package:platform_object_channel/platform_object_channel.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  dynamic _methodResult = 'Unknown';
  dynamic _streamMethodResult = 'Unknown';

  @override
  void initState() {
    super.initState();

    // 创建平台对象通道
    final platformObjectInstance = PlatformObjectChannel(
      Platform.isAndroid ? "com.example.example.TestObject" : "TestObject",
      "arguments"
    );

    // 设置方法调用处理器
    platformObjectInstance.setPlatformObjectMethodCallHandler(
      (method, arguments) async {
        if (method == "sayHi") {
          return "reply from flutter";
        }
      },
    );

    // 调用方法并获取结果
    Future(() async {
      _methodResult = await platformObjectInstance.invokeMethod("sayHi", "im flutter");
      setState(() {});
    });

    // 订阅流方法并处理结果
    Future(() async {
      await for (var element in platformObjectInstance.invokeMethodStream("sayHi_10", "im flutter, 10")) {
        setState(() {
          _streamMethodResult = element;
        });
      }
    });
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Plugin example app'),
        ),
        body: Column(
          children: [
            Text("method result: $_methodResult"),
            Text("stream method result: $_streamMethodResult"),
          ],
        ),
      ),
    );
  }
}

iOS 和 macOS 示例

@objc(TestObject)
class TestObject : NSObject, FoundationPlatformObject {
    required init(_ flutterArgs: Any?, _ messager: FoundationPlatformObjectMessenger) {
        self.messager = messager
    }

    let messager: FoundationPlatformObjectMessenger

    // 处理方法调用
    func handleFlutterMethodCall(_ method: String, _ arguments: Any?) async -> Any? {
        Task {
            var result = await messager.invokeMethod("sayHi", "hi")
            print("flutter return \(result ?? "")")
        }
        return "Hi"
    }

    // 处理流方法调用
    func handleFlutterStreamMethodCall(_ method: String, _ arguments: Any?, _ sink: platform_object_channel_foundation.FoundationPlatformStreamMethodSink) {
        var count = 10
        Timer.scheduledTimer(withTimeInterval: 1, repeats: true) { timer in
            count -= 1
            if count <= 0 {
                timer.invalidate()
                sink.done()
            } else {
                sink.add("Hi \(count)")
            }
        }
    }

    // 释放资源
    func dispose() {
        // 释放资源
    }
}

Android 示例

class TestObject : AndroidPlatformObject {
    private lateinit var messager: AndroidPlatformObjectMessenger

    // 初始化
    override fun setUp(flutterArgs: Any?, messager: AndroidPlatformObjectMessenger) {
        this.messager = messager
    }

    // 处理方法调用
    override suspend fun handleFlutterMethodCall(method: String, arguments: Any?): Any? {
        GlobalScope.launch(Dispatchers.Default) {
            var result = messager.invokeMethod("sayHi", "hi")
            print("flutter return $result")
        }
        return "Hi"
    }

    // 处理流方法调用
    override fun handleFlutterStreamMethodCall(
        method: String,
        arguments: Any?,
        sink: AndroidPlatformStreamMethodSink
    ) {
        var count = 0
        GlobalScope.launch {
            while (true) {
                count++
                if (count > 10) {
                    sink.done()
                } else {
                    sink.add(count)
                }
                delay(1000)
            }
        }
    }

    // 释放资源
    override fun dispose() {
        // 释放资源
    }
}