网络信息和 WifiConfiguration 在 SDK 22 中已被弃用

Question

我在 PAX A920 设备（SDK 版本 22）中使用 android 棒棒糖。 我在构建时收到这样的警告消息：

NetworkInfo in android.net has been deprecated

WifiConfiguration in android.net has been deprecated

我很困惑，因为我在C:\\Users\\{YOUR_ACCOUNT}\\AppData\\Local\\Android\\Sdk\\sources\\android-22\\com\\android\\connectivitymanagertest中看到了一个使用该方法访问 wifi 的C:\\Users\\{YOUR_ACCOUNT}\\AppData\\Local\\Android\\Sdk\\sources\\android-22\\com\\android\\connectivitymanagertest ，但是为什么它似乎已被弃用？

什么方法可以替换已弃用的方法？

public boolean isWifiConnected() {
    boolean isWifiConnected = false;
    try {
        NetworkInfo networkInfo = connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
        if (networkInfo != null) {
            isWifiConnected = networkInfo.getState() == CONNECTED;
        }
        Log.i(TAG, "wifi adapter is connected? " + isWifiConnected);
    } catch (Exception ex) {
        ex.printStackTrace();
    }
    return isWifiConnected;
}

public void removeNetwork() {
    List<WifiConfiguration> wifiCfgList = wifiManager.getConfiguredNetworks();
    if (wifiCfgList.size() > 0) {
        for (WifiConfiguration item : wifiCfgList) {
            if (item != null) {
                wifiManager.removeNetwork(item.networkId);
                wifiManager.saveConfiguration();
            }
        }
    }
}

谢谢指出。

Answer 1

不推荐使用的类被重新命名为ConnectivityManager系统服务和NetworkCallbacks ： https : //developer.android.com/training/monitoring-device-state/connectivity-status-type

尽管官方代码示例显示了如何从ConnectivityManager获取NetworkInfo ，但还是有一个突出显示的注释：

以下是如何获取当前网络状态并随着时间的推移接收更新的示例代码。 这是我将在生产中使用的部分精简解决方案。 如果您将它与 RxJava 或 RxKotlin 连接，您可以创建一个可观察的对象，该对象将保存网络状态，并在调用 NetworkCallback 的重写方法时进行更新。

关于 Java 的注意事项：为了简洁起见，公共类级变量被公开。 我会为这些创建一些 getter 来访问这些变量背后的值。

随意问的问题。

爪哇

class NetworkReachabilityService {

    public NetworkType networkType;
    public NetworkState networkState = NetworkState.Unavailable;
    private ConnectivityManager connectivityManager;
    private ConnectivityManager.NetworkCallback networkCallback = new ConnectivityManager.NetworkCallback() {
        @Override
        public void onAvailable(@NonNull Network network) {
            super.onAvailable(network);
            updateAvailability(connectivityManager.getNetworkCapabilities(network));
        }

        @Override
        public void onLosing(@NonNull Network network, int maxMsToLive) {
            super.onLosing(network, maxMsToLive);
            networkState = NetworkState.Losing;
        }

        @Override
        public void onLost(@NonNull Network network) {
            super.onLost(network);
            networkState = NetworkState.Lost;
        }

        @Override
        public void onUnavailable() {
            super.onUnavailable();
            networkState = NetworkState.Unavailable;
        }

        @Override
        public void onCapabilitiesChanged(@NonNull Network network, @NonNull NetworkCapabilities networkCapabilities) {
            super.onCapabilitiesChanged(network, networkCapabilities);
            updateAvailability(networkCapabilities);
        }
    };

    public NetworkReachabilityService(Context context) {
        connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    }

    private void updateAvailability(NetworkCapabilities networkCapabilities) {
        if (networkCapabilities == null) {
            networkState = NetworkState.Unavailable;
            return;
        }

        if (networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
            networkType = NetworkType.CELL;
        } else if (networkCapabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
            networkType = NetworkType.WiFi;
        }

        networkState = NetworkState.Available;
    }

    public void resumeListeningNetworkChanges() {
        pauseListeningNetworkChanges();
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
            connectivityManager.registerDefaultNetworkCallback(networkCallback);
        } else {
            connectivityManager.registerNetworkCallback(
                    new NetworkRequest.Builder().build(),
                    networkCallback
            );
        }
    }

    public void pauseListeningNetworkChanges() {
        try {
            connectivityManager.unregisterNetworkCallback(networkCallback);
        } catch (IllegalArgumentException exception) {
            // Usually happens only once if: "NetworkCallback was not registered"
        }
    }

    private enum NetworkState {
        Available, Unavailable, Connecting, Losing, Lost
    }

    private enum NetworkType {
        WiFi, CELL, OTHER
    }
}

科特林

sealed class NetworkState {
    data class Available(val type: NetworkType) : NetworkState()
    object Unavailable : NetworkState()
    object Connecting : NetworkState()
    object Losing : NetworkState()
    object Lost : NetworkState()
}

sealed class NetworkType {
    object WiFi : NetworkType()
    object CELL : NetworkType()
    object OTHER : NetworkType()
}

class NetworkReachabilityService private constructor(context: Context) {
    
    private val connectivityManager: ConnectivityManager =
        context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
    private val networkCallback = object : ConnectivityManager.NetworkCallback() {
        // There are more functions to override!

        override fun onLost(network: Network) {
            super.onLost(network)
            networkState = NetworkState.Lost
        }

        override fun onUnavailable() {
            super.onUnavailable()
            networkState = NetworkState.Unavailable
        }

        override fun onLosing(network: Network, maxMsToLive: Int) {
            super.onLosing(network, maxMsToLive)
            networkState = NetworkState.Losing
        }

        override fun onAvailable(network: Network) {
            super.onAvailable(network)
            updateAvailability(connectivityManager.getNetworkCapabilities(network))
        }

        override fun onCapabilitiesChanged(
            network: Network,
            networkCapabilities: NetworkCapabilities
        ) {
            super.onCapabilitiesChanged(network, networkCapabilities)
            updateAvailability(networkCapabilities)
        }
    }
    
    var networkState: NetworkState = NetworkState.Unavailable
        private set

    private fun updateAvailability(networkCapabilities: NetworkCapabilities?) {
        if (networkCapabilities == null) {
            networkState = NetworkState.Unavailable
            return
        }
        var networkType: NetworkType = NetworkType.OTHER

        if (networkCapabilities.hasTransport(TRANSPORT_CELLULAR)) {
            networkType = NetworkType.CELL
        }
        if (networkCapabilities.hasTransport(TRANSPORT_WIFI)) {
            networkType = NetworkType.WiFi
        }

        networkState = NetworkState.Available(networkType)
    }

    fun pauseListeningNetworkChanges() {
        try {
            connectivityManager.unregisterNetworkCallback(networkCallback)
        } catch (e: IllegalArgumentException) {
            // Usually happens only once if: "NetworkCallback was not registered"
        }
    }

    fun resumeListeningNetworkChanges() {
        pauseListeningNetworkChanges()
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
            connectivityManager.registerDefaultNetworkCallback(networkCallback)
        } else {
            connectivityManager.registerNetworkCallback(
                NetworkRequest.Builder().build(),
                networkCallback
            )
        }
    }
}

要开始接收网络状态更新，请分别调用resumeListeningNetworkChanges和停止pauseListeningNetworkChanges 。

更新：如何在弃用和新 API 之间切换

请注意，即使您使用此解决方案，您仍然会收到一条消息，表明您使用的某些代码已被弃用！ 只要您提供可以在新 API 和旧的、已弃用的 API 之间切换的实现，它就完全没问题，不会被视为错误。

这是一个近似的解决方案。 由于新类是在 API 级别 29 中添加的，我们必须使用Build.VERSION_CODES.Q因为它是一个值为29的整数。

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {         
   // Use new API here
} else {
   // Use old API here
}