对于每一个阅读这一点，问题不是从我的Flutter代码，它是从我的nginx配置，我必须添加以下行到/etc/nginx/conf.d/sysmon.conf文件：

location / {
        proxy_set_header   X-Forwarded-For $remote_addr;
        proxy_http_version  1.1;
        proxy_set_header    Upgrade $http_upgrade;
        proxy_set_header    Connection "upgrade";
        proxy_set_header    Host $http_host;
        proxy_set_header    X-Real-IP $remote_addr;
        proxy_set_header   Host $http_host;
        proxy_pass         http://<SERVER_IP>:<PORT>;
    }

您可以扩展HttpOverides类并重写HttpClient方法来更改securityContext。这主要发生在Android 7及以下的用户身上。

class MyHttpOverrides extends HttpOverrides {
  @override
  HttpClient createHttpClient(SecurityContext? context) {
    return super.createHttpClient(context)
      ..badCertificateCallback =
          (X509Certificate cert, String host, int port) => true;
   }
  }

并在主目录中声明

Future<void> main() async {
  HttpOverrides.global = MyHttpOverrides();
 runApp(const MyApp());
}

如果你在后台服务中运行WebSocket通道，当WebSocket断开连接时，你需要定期重新连接到服务器，确保你在你的start方法中添加HttpOverrides.global = MyHttpOverrides();，如果你像这样使用flutter_background_service包，

@pragma('vm:entry-point')
Future<void> onStart(ServiceInstance service) async {
  HttpOverrides.global = MyHttpOverrides();
// Your Websocket connection code goes here
}