如何使用flutter中的布局打开特定的android活动

Intent intent = new Intent(this, SpecificActivity.class);
startActivity(intent);

import 'package:flutter/services.dart';

final platform = MethodChannel('com.example/platform_channel');

void openSpecificActivity() async {
  try {
    await platform.invokeMethod('openSpecificActivity');
  } catch (e) {
    print('Error: $e');
  }
}

MethodChannel channel = new MethodChannel(getFlutterEngine().getDartExecutor().getBinaryMessenger(), "com.example/platform_channel");
channel.setMethodCallHandler(
  (call, result) -> {
    if (call.method.equals("openSpecificActivity")) {
      Intent intent = new Intent(this, SpecificActivity.class);
      startActivity(intent);
      result.success(null);
    } else {
      result.notImplemented();
    }
  }
);