如何使用API从flutter插件启动活动

import 'package:flutter/services.dart';

// 创建一个platform channel
final platform = MethodChannel('com.example.flutter_app/channel');

// 调用Android原生代码启动活动
void startNativeActivity() async {
  try {
    await platform.invokeMethod('startNativeActivity');
  } on PlatformException catch (e) {
    print("Failed to start native activity: ${e.message}");
  }
}

import android.content.Intent;
import android.os.Bundle;

import io.flutter.embedding.android.FlutterActivity;
import io.flutter.embedding.engine.FlutterEngine;
import io.flutter.plugin.common.MethodCall;
import io.flutter.plugin.common.MethodChannel;
import io.flutter.plugins.GeneratedPluginRegistrant;

public class MainActivity extends FlutterActivity {
    private static final String CHANNEL = "com.example.flutter_app/channel";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        GeneratedPluginRegistrant.registerWith(this);

        // 设置MethodChannel用于与Flutter通信
        new MethodChannel(getFlutterEngine().getDartExecutor().getBinaryMessenger(), CHANNEL)
                .setMethodCallHandler(
                        (call, result) -> {
                            if (call.method.equals("startNativeActivity")) {
                                startNativeActivity();
                            } else {
                                result.notImplemented();
                            }
                        }
                );
    }

    private void startNativeActivity() {
        Intent intent = new Intent(this, NativeActivity.class);
        startActivity(intent);
    }
}