problem_check_system/lib/data/providers/network_status_service.dart

// lib/data/providers/connectivity_provider.dart
import 'dart:async';
import 'package:connectivity_plus/connectivity_plus.dart';
import 'package:get/get.dart';

class NetworkStatusService extends GetxService {
  final Connectivity _connectivity = Connectivity();
  final RxBool isOnline = false.obs;
  StreamSubscription<List<ConnectivityResult>>? _connectivitySubscription;

  @override
  void onInit() {
    super.onInit();
    _initConnectivityListener();
    _checkInitialConnectivity();
  }

  @override
  void onClose() {
    _connectivitySubscription?.cancel();
    super.onClose();
  }

  void _initConnectivityListener() {
    _connectivitySubscription = _connectivity.onConnectivityChanged.listen((
      results,
    ) {
      isOnline.value = _isConnected(results);
      // UI 层监听 isOnline.value 变化后自行处理提示
    });
  }

  Future<void> _checkInitialConnectivity() async {
    final initialResults = await _connectivity.checkConnectivity();
    isOnline.value = _isConnected(initialResults);
  }

  bool _isConnected(List<ConnectivityResult> results) {
    return results.any(
      (result) =>
          result == ConnectivityResult.mobile ||
          result == ConnectivityResult.wifi ||
          result == ConnectivityResult.ethernet,
    );
  }
}