如何以编程方式连接到 Android 中的特定 Wi-Fi 网络？

Question

我想设计一个显示可用 Wi-Fi 网络列表并连接到用户选择的任何网络的应用程序。

我已经实现了显示扫描结果的部分。现在我想连接到用户从扫描结果列表中选择的特定网络。

我该怎么做呢？

原文由 Vikram Gupta 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

您需要创建 WifiConfiguration 这样的实例：

 String networkSSID = "test";
String networkPass = "pass";

WifiConfiguration conf = new WifiConfiguration();
conf.SSID = "\"" + networkSSID + "\"";   // Please note the quotes. String should contain ssid in quotes

然后，对于 WEP 网络，您需要执行以下操作：

 conf.wepKeys[0] = "\"" + networkPass + "\"";
conf.wepTxKeyIndex = 0;
conf.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE);
conf.allowedGroupCiphers.set(WifiConfiguration.GroupCipher.WEP40);

对于 WPA 网络，您需要像这样添加密码：

 conf.preSharedKey = "\""+ networkPass +"\"";

对于开放网络，您需要这样做：

 conf.allowedKeyManagement.set(WifiConfiguration.KeyMgmt.NONE);

然后，您需要将其添加到 Android wifi 管理器设置：

 WifiManager wifiManager = (WifiManager)context.getSystemService(Context.WIFI_SERVICE);
wifiManager.addNetwork(conf);

最后，您可能需要启用它，以便 Android 连接到它：

 List<WifiConfiguration> list = wifiManager.getConfiguredNetworks();
for( WifiConfiguration i : list ) {
    if(i.SSID != null && i.SSID.equals("\"" + networkSSID + "\"")) {
         wifiManager.disconnect();
         wifiManager.enableNetwork(i.networkId, true);
         wifiManager.reconnect();

         break;
    }
 }

UPD：在 WEP 的情况下，如果您的密码是十六进制的，则不需要用引号括起来。

原文由 kenota 发布，翻译遵循 CC BY-SA 3.0 许可协议

Answer 2

获取 Wifi 列表，连接到 Wifi（Android <=9 和 Android >=10）

 [assembly: Xamarin.Forms.Dependency(typeof(WifiService))]
namespace configurator.Droid.Services
{
   public class WifiService : IWifiService
 {
    private bool _requested;
    private bool _statusConnect;

    private NetworkCallback _callback;
    private Context _context = null;
    private Version _version;
    private WifiManager _wifiManager = null;
    private ConnectivityManager _connectivityManager;
    private WifiConfiguration _config;
    private int _temp = -1;

    public WifiService()
    {
        this._context = Android.App.Application.Context;
        _version = DeviceInfo.Version;
        _wifiManager = _context.GetSystemService(Context.WifiService) as WifiManager;
    }

    [Obsolete]
    public async Task<bool> ConnectToWifiAsync(string ssid, string password, Action<bool> animation = null)
    {
        if (!_wifiManager.IsWifiEnabled)
        {
            if (_version.Major >= 9)
            {
                bool result =  await Device.InvokeOnMainThreadAsync(async () => await Application.Current.MainPage.DisplayAlert("", "The program requires accesss to Wi-Fi. Turn on Wi-fi?", "Ok", "Cancel")) ;

                if (!result)
                {
                    return false;
                }

                Intent intent;

                if (_version.Major == 9)
                {
                    intent = new Intent(Android.Provider.Settings.ActionWifiSettings);
                }
                else
                {
                    intent = new Intent(Android.Provider.Settings.Panel.ActionInternetConnectivity);
                }

                intent.AddFlags(ActivityFlags.NewTask);
                Android.App.Application.Context.StartActivity(intent);
            }
            else
            {
                _wifiManager.SetWifiEnabled(true);
            }
        }
        else
        {

            if (_version.Major <= 9 && _version.Major >= 8)
            {
                await Device.InvokeOnMainThreadAsync(async () => await Geolocation.GetLastKnownLocationAsync());
                JoinToWifiLessAndroidQAsync(ssid, password, animation);
            }
            else if(_version.Major < 8)
            {
                JoinToWifiLessAndroidQAsync(ssid, password, animation);
            }
            else
            {
                await Device.InvokeOnMainThreadAsync(async () => await Geolocation.GetLastKnownLocationAsync());
                await JoinToWifiMoreAndroidPie(ssid, password);
            }
        }

        return await Task.FromResult(_statusConnect);
    }

    [Obsolete]
    public async Task<IEnumerable<string>> GetAvailableNetworksAsync()
    {

        IEnumerable<string> availableNetworks = null;

        // Get a handle to the Wifi
        if (!_wifiManager.IsWifiEnabled)
            _wifiManager.SetWifiEnabled(true);
        var wifiReceiver = new WifiReceiver(_wifiManager);

        await Task.Run(() =>
        {
            // Start a scan and register the Broadcast receiver to get the list of Wifi Networks
            _context.RegisterReceiver(wifiReceiver, new IntentFilter(WifiManager.ScanResultsAvailableAction));
            availableNetworks = wifiReceiver.Scan();
        });

        return availableNetworks;
    }

    private class NetworkCallback : ConnectivityManager.NetworkCallback
    {
        private ConnectivityManager _connectivityManager;

        public NetworkCallback(ConnectivityManager connectivityManager)
        {
            _connectivityManager = connectivityManager;
        }
        public Action<Network> NetworkAvailable { get; set; }
        public Action NetworkUnavailable { get; set; }

        public override void OnAvailable(Network network)
        {
            _connectivityManager.BindProcessToNetwork(network);
            base.OnAvailable(network);
            NetworkAvailable?.Invoke(network);
        }

        public override void OnUnavailable()
        {
            base.OnUnavailable();
            NetworkUnavailable?.Invoke();
        }
    }

    [BroadcastReceiver(Enabled = true, Exported = false)]
    class WifiReceiver : BroadcastReceiver
    {
        private WifiManager _wifi;
        private List<string> _wifiNetworks;
        private AutoResetEvent _receiverARE;
        private Timer _tmr;
        private const int TIMEOUT_MILLIS = 20000; // 20 seconds timeout

        public WifiReceiver()
        {

        }

        public WifiReceiver(WifiManager wifi)
        {
            this._wifi = wifi;
            _wifiNetworks = new List<string>();
            _receiverARE = new AutoResetEvent(false);
        }

        [Obsolete]
        public IEnumerable<string> Scan()
        {
            _tmr = new Timer(Timeout, null, TIMEOUT_MILLIS, System.Threading.Timeout.Infinite);
            _wifi.StartScan();
            _receiverARE.WaitOne();
            return _wifiNetworks;
        }

        public override void OnReceive(Context context, Intent intent)
        {
            IList<ScanResult> scanwifinetworks = _wifi.ScanResults;
            foreach (ScanResult wifinetwork in scanwifinetworks)
            {
                _wifiNetworks.Add(wifinetwork.Ssid);
            }

            _receiverARE.Set();
        }

        private void Timeout(object sender)
        {
            // NOTE release scan, which we are using now, or we throw an error?
            _receiverARE.Set();
        }
    }

    [Obsolete]
    private void JoinToWifiLessAndroidQAsync(string ssid, string password, Action<bool> animation)
    {
        animation?.Invoke(true);

        _config = new WifiConfiguration
        {
            Ssid = "\"" + ssid + "\"",
            PreSharedKey = "\"" + password + "\""
        };

        try
        {
            _temp = _wifiManager.AddNetwork(_config);
            _wifiManager.Disconnect();
            var result = _wifiManager.EnableNetwork(_temp, true);
            _wifiManager.Reconnect();

            int i = 0;

            do
            {
                Thread.Sleep(2000);
                //wait connection
                i++;
                if (i == 7)
                    break;

            } while (GetCurrentConnectName() != ssid);

            Thread.Sleep(6000);

            if (i == 7)
            {
                throw new Exception("Connect to PC failed. Long time connect(14000ms)");
            }
            else
            {
                _statusConnect = true;
            }
        }
        catch (Exception ex)
        {
            Helpers.Logger.Error($"{nameof(WifiService)}||JoinToWifiLessAndroidQ||{ex.Message}");
            _statusConnect = false;
        }
    }

    [Obsolete]
    private async Task<bool> JoinToWifiMoreAndroidPie(string ssid, string password)
    {
        var specifier = new WifiNetworkSpecifier.Builder()
                       .SetSsid(ssid)
                       .SetWpa2Passphrase(password)
                       .Build();

        var request = new NetworkRequest.Builder()
                       .AddTransportType(TransportType.Wifi)
                       .RemoveCapability(NetCapability.Internet)
                       .SetNetworkSpecifier(specifier)
                       .Build();

        _connectivityManager = _context.GetSystemService(Context.ConnectivityService) as ConnectivityManager;

        if (_requested)
        {
            _connectivityManager.UnregisterNetworkCallback(_callback);
        }

        bool confirmConnect = false;

        _callback = new NetworkCallback(_connectivityManager)
        {
            NetworkAvailable = network =>
            {
                // we are connected!
                _statusConnect = true;
                confirmConnect = true;
            },
            NetworkUnavailable = () =>
            {
                _statusConnect = false;
                confirmConnect = true;
            }
        };

        _connectivityManager.RequestNetwork(request, _callback);
        _requested = true;

        do
        {
            //wait callback
            await Task.Delay(TimeSpan.FromSeconds(5));
            Helpers.Logger.Info($"{nameof(WifiService)}||JoinToWifiMoreAndroidPie||Waiting callback....");

        } while (!confirmConnect);

        return await Task.FromResult(true);
    }

    public string GetCurrentConnectName()
    {
        WifiInfo wifiInfo = _wifiManager.ConnectionInfo;
        if (wifiInfo.SupplicantState == SupplicantState.Completed)
        {
            char[] chars = {'\"'};
            var masChar = wifiInfo.SSID.Trim(chars);
            return masChar;
        }
        else
        {
            return null;
        }
    }

    [Obsolete]
    public async Task ReconnectToWifi()
    {
        if (_version.Major > 9)
        {
            _connectivityManager.UnregisterNetworkCallback(_callback);
            await Task.Delay(10000);
            var network = _connectivityManager.ActiveNetwork;

            if(network == null)
            {
                var dataNetwork = await ManagerSecureStorage.GetConnectedNetworkInfo();
                await JoinToWifiMoreAndroidPie(dataNetwork["NetName"], dataNetwork["Password"]);
            }
            else
            {
                _connectivityManager.BindProcessToNetwork(network);
            }
        }
        else
        {
            if(_temp == -1)
            {
                var temp = _wifiManager.ConfiguredNetworks;
                _temp = temp.Last().NetworkId;
            }

            _wifiManager.RemoveNetwork(_temp);
            _wifiManager.Reconnect();
            await Task.Delay(10000);
        }
    }
  }
}

原文由 Denys Tsurkanovski 发布，翻译遵循 CC BY-SA 4.0 许可协议