dependencies:
  flutter:
    sdk: flutter
  # The following adds the Cupertino Icons font to your application.
  # Use with the CupertinoIcons class for iOS style icons.
  cupertino_icons: ^1.0.2
  connectivity_plus: ^4.0.1

android {
    ...
    defaultConfig {
        applicationId "com.example.flutter_application_connectivity"
        minSdkVersion 19 //flutter.minSdkVersion
          targetSdkVersion flutter.targetSdkVersion
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
    }

class _ConnectivityPageState extends State<ConnectivityPage> {
  // Connectivity 對(duì)象
  final Connectivity _connectivity = Connectivity();

// 消息訂閱
  late StreamSubscription<ConnectivityResult> _subscription;

// 初始返回的網(wǎng)絡(luò)狀態(tài)
  ConnectivityResult? _connectivityStatus;

// 初始化
  Future<void> _init() async {
    try {
      // 方式1：?jiǎn)未握?qǐng)求檢查
      final connectivityResult = await _connectivity.checkConnectivity();
      _updateConnectionStatus(connectivityResult);
    } on PlatformException catch (e) {
      print(e);
      print('連接網(wǎng)絡(luò)出現(xiàn)了異常');
    }
  }

// 初始化
  Future<void> _init() async {
    try {
      // 方式1：?jiǎn)未握?qǐng)求檢查
      // final connectivityResult = await _connectivity.checkConnectivity();
      // _updateConnectionStatus(connectivityResult);
      // 方式2：狀態(tài)訂閱
      _subscription =
          _connectivity.onConnectivityChanged.listen(_updateConnectionStatus);
    } on PlatformException catch (e) {
      print(e);
      print('連接網(wǎng)絡(luò)出現(xiàn)了異常');
    }
  }

Future<void> _updateConnectionStatus(ConnectivityResult result) async {
    setState(() {
      _connectivityStatus = result;
    });
    if (result == ConnectivityResult.mobile) {
      print('成功連接移動(dòng)網(wǎng)絡(luò)');
    } else if (result == ConnectivityResult.wifi) {
      print('成功連接WIFI');
    } else if (result == ConnectivityResult.ethernet) {
      print('成功連接到以太網(wǎng)');
    } else if (result == ConnectivityResult.vpn) {
      print('成功連接vpn網(wǎng)絡(luò)');
    } else if (result == ConnectivityResult.bluetooth) {
      print('成功連接藍(lán)牙');
    } else if (result == ConnectivityResult.other) {
      print('成功連接除以上以外的網(wǎng)絡(luò)');
    } else if (result == ConnectivityResult.none) {
      print('沒(méi)有連接到任何網(wǎng)絡(luò)');
    }
  }

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

@override
  void dispose() {
    _subscription.cancel();
    super.dispose();
  }

@override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('網(wǎng)路連接檢查'),
      ),
      body: Center(
        child: Column(
          children: [
            const Text('狀態(tài)'),
            Text(_connectivityStatus?.toString() ?? "未知"),
          ],
        ),
      ),
    );
  }