Question

使用compileSdkVersion 23，但是尝试支持9。

getNetworkInfo（int）在23中已弃用。建议改为使用getAllNetworks和getNetworkInfo（Network）。但是，这两者都需要最低限度的API 21。

我们可以在支持包中使用哪个类可以帮助解决这个问题吗？

我知道提出了一个解决方案before，但是我对9的最低api要求的挑战造成了问题。

Answer 1

您可以使用：

getActiveNetworkInfo（）;

        ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
        if (activeNetwork != null) { 
            // connected to the internet
            if (activeNetwork.getType() == ConnectivityManager.TYPE_WIFI) {
                // connected to wifi
            } else if (activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE) {
                // connected to mobile data
            }
        } else {
            // not connected to the internet
        }

或在开关案例中

        ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
        if (activeNetwork != null) { 
            // connected to the internet
            switch (activeNetwork.getType()) {
                case ConnectivityManager.TYPE_WIFI:
                    // connected to wifi
                    break;
                case ConnectivityManager.TYPE_MOBILE:
                    // connected to mobile data
                    break;
                default:
                    break;
            }
        } else {
            // not connected to the internet
        }

Answer 2

更新回答（19：07：2018）：

此方法可帮助您检查互联网连接是否可用。

public static boolean isNetworkAvailable(Context context) {
    ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);

    if (connectivityManager != null) {
        NetworkInfo activeNetwork = connectivityManager.getActiveNetworkInfo();
        return (activeNetwork != null && activeNetwork.isConnectedOrConnecting());
    } else {
        return false;
    }
}

旧回答：

为了最好的代码重用实践，即兴创作奶酪面包回答。

public static boolean isNetworkAvailable(Context context) {
    int[] networkTypes = {ConnectivityManager.TYPE_MOBILE,
            ConnectivityManager.TYPE_WIFI};
    try {
        ConnectivityManager connectivityManager =
                (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        for (int networkType : networkTypes) {
            NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
            if (activeNetworkInfo != null &&
                    activeNetworkInfo.getType() == networkType)
                return true;
        }
    } catch (Exception e) {
        return false;
    }
    return false;
}

代码可以放在Util类中，可用于检查手机是否通过Wifi或移动互联网从应用程序的任何部分连接到Internet。

Answer 3

至2018年10月，已接受的答案已弃用。

getType()及其类型本身现已在API级别28中弃用。来自Javadoc：

呼叫者应改用使用NetworkCapabilities＃TRANSPORT *常量之一来检查NetworkCapabilities＃hasTransport

要使用NetworkCapabilities，您需要将Network实例传递给getNetworkCapabilities()方法。要获取该实例，您需要调用API级别23中添加的getActiveNetwork()。

因此，我认为目前安全检查您是否已连接到Wi-Fi或蜂窝网络的正确方法是：

public static boolean isNetworkConnected() {
    final ConnectivityManager cm = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);

    if (cm != null) {
        if (Build.VERSION.SDK_INT < 23) {
            final NetworkInfo ni = cm.getActiveNetworkInfo();

            if (ni != null) {
                return (ni.isConnected() && (ni.getType() == ConnectivityManager.TYPE_WIFI || ni.getType() == ConnectivityManager.TYPE_MOBILE));
            }
        } else {
            final Network n = cm.getActiveNetwork();

            if (n != null) {
                final NetworkCapabilities nc = cm.getNetworkCapabilities(n);

                return (nc.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR) || nc.hasTransport(NetworkCapabilities.TRANSPORT_WIFI));
            }
        } 
    }

    return false; 
}

您还可以检查其他类型的TRANSPORT，您可以找到here。

重要说明：：如果您已连接到Wi-Fi 和到VPN，则当前状态可能是TRANSPORT_VPN，因此您可能想要也检查一下。

请不要忘记为您的AndroidManifest文件添加以下权限：

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Answer 4

在28 (Android P)中不再推荐使用的答案，但是其替换方法仅适用于23 (Android M)。为了支持较旧的设备，我编写了一个辅助函数。

使用方法：

int type = getConnectionType(getApplicationContext());

它返回一个int，您可以在代码中将其更改为enum：

0：没有可用的互联网（可能是在飞行模式下，或者正在加入wi-fi）。

1：蜂窝（移动数据，3G / 4G / LTE等等）。

2：Wi-fi。

您可以复制辅助功能的Kotlin或Java版本。

科特琳：

@IntRange(from = 0, to = 2)
fun getConnectionType(context: Context): Int {
    var result = 0 // Returns connection type. 0: none; 1: mobile data; 2: wifi
    val cm = context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager?
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        cm?.run {
            cm.getNetworkCapabilities(cm.activeNetwork)?.run {
                if (hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
                    result = 2
                } else if (hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
                    result = 1
                }
            }
        }
    } else {
        cm?.run {
            cm.activeNetworkInfo?.run {
                if (type == ConnectivityManager.TYPE_WIFI) {
                    result = 2
                } else if (type == ConnectivityManager.TYPE_MOBILE) {
                    result = 1
                }
            }
        }
    }
    return result
}

Java：

@IntRange(from = 0, to = 2)
public static int getConnectionType(Context context) {
    int result = 0; // Returns connection type. 0: none; 1: mobile data; 2: wifi
    ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        if (cm != null) {
            NetworkCapabilities capabilities = cm.getNetworkCapabilities(cm.getActiveNetwork());
            if (capabilities != null) {
                if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
                    result = 2;
                } else if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
                    result = 1;
                }
            }
        }
    } else {
        if (cm != null) {
            NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
            if (activeNetwork != null) {
                // connected to the internet
                if (activeNetwork.getType() == ConnectivityManager.TYPE_WIFI) {
                    result = 2;
                } else if (activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE) {
                    result = 1;
                }
            }
        }
    }
    return result;
}

Answer 5

许多答案仍然使用23以下的 getNetworkType （已弃用）；使用下面的代码检查设备是否可以连接互联网。

public static boolean isNetworkConnected(Context context) {

    ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);

    if (cm != null) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            NetworkCapabilities capabilities = cm.getNetworkCapabilities(cm.getActiveNetwork());
            return capabilities != null && (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI) || capabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR));
        } else {
            NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
            return activeNetwork != null && activeNetwork.isConnected();
        }
    }

    return false;
}

..

而且，不要忘记在清单中添加此行

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Answer 6

如芝士面包所示，请使用 getActiveNetworkInfo（）

getActiveNetworkInfo

在API级别1中添加

NetworkInfo getActiveNetworkInfo（）

返回有关当前活动的默认数据网络的详细信息。连接时，此网络是传出连接的默认路由。在启动网络流量之前，您应该始终检查isConnected（）。当没有默认网络时，这可能返回null。   此方法要求调用者持有权限ACCESS_NETWORK_STATE。   返回   的NetworkInfo   当前默认网络的NetworkInfo对象;如果当前没有默认网络，则为null。

参考：Android Studio

 public final boolean isInternetOn() {

    // get Connectivity Manager object to check connection
    ConnectivityManager connec =
            (ConnectivityManager)getSystemService(getBaseContext().CONNECTIVITY_SERVICE);

    // Check for network connections
    if ( connec.getActiveNetworkInfo().getState() == android.net.NetworkInfo.State.CONNECTED ||
            connec.getActiveNetworkInfo().getState() == android.net.NetworkInfo.State.CONNECTING ) {

        // if connected with internet

        Toast.makeText(this, connec.getActiveNetworkInfo().getTypeName(), Toast.LENGTH_LONG).show();
        return true;

    } else if (
            connec.getActiveNetworkInfo().getState() == android.net.NetworkInfo.State.DISCONNECTED ||
                    connec.getActiveNetworkInfo().getState() == android.net.NetworkInfo.State.DISCONNECTED  ) {

        Toast.makeText(this, " Not Connected ", Toast.LENGTH_LONG).show();
        return false;
    }
    return false;
}

现在调用方法，为了安全使用try catch

     try {
     if(isInternetOn()){ //connected actions }
    else{
    //not connected actions }

        }catch (Exception e){
            Toast.makeText(this, e.getMessage(), Toast.LENGTH_SHORT).show();
        }

不要忘记添加：

    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Answer 7

这可以帮助某人 科特林

fun isNetworkConnected(context: Context) : Boolean {
        val connectivityManager = context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
        val capabilities =  connectivityManager.getNetworkCapabilities(connectivityManager.activeNetwork)
        capabilities.also {
            if (it != null){
                if (it.hasTransport(NetworkCapabilities.TRANSPORT_WIFI))
                    return true
                else if (it.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)){
                    return true
                }
            }
        }
        return false
    }

Answer 8

要检查您是否在线：

boolean isOnline() {
    // Checking internet connectivity
    ConnectivityManager connectivityMgr = (ConnectivityManager) this.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo activeNetwork = null;
    if (connectivityMgr != null) {
        activeNetwork = connectivityMgr.getActiveNetworkInfo();
    }
    return activeNetwork != null;
}

获取android M之前/之后的Internet连接类型

void internetType() {
    // Checking internet connectivity
    ConnectivityManager connectivityMgr = (ConnectivityManager) this.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo activeNetwork = null;
    if (connectivityMgr != null) {
        activeNetwork = connectivityMgr.getActiveNetworkInfo();
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            NetworkCapabilities nc = connectivityMgr.getNetworkCapabilities(connectivityMgr.getActiveNetwork());
            if (nc.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
                // connected to mobile data
            } else if (nc.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
                // connected to wifi
            }
        } else {
            if (activeNetwork.getType() == ConnectivityManager.TYPE_WIFI) {
                // connected to wifi
            } else if (activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE) {
                // connected to mobile data
            }
        }
    }
}

所有情况下都需要访问网络状态的权限

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Answer 9

为了安全起见，我建议也使用方法

NetworkInfo.isConnected（）

整个方法如下：

/**
 * Checking whether network is connected
 * @param context Context to get {@link ConnectivityManager}
 * @return true if Network is connected, else false
 */
public static boolean isConnected(Context context){
    ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
    if (activeNetwork != null && activeNetwork.isConnected()) {
        int networkType = activeNetwork.getType();
        return networkType == ConnectivityManager.TYPE_WIFI || networkType == ConnectivityManager.TYPE_MOBILE;
    } else {
        return false;
    }
}

Answer 10

科特林版本：

fun isInternetOn(context: Context): Boolean {
   val cm = context.getSystemService(Context.CONNECTIVITY_SERVICE) as? ConnectivityManager
   val activeNetwork = cm?.activeNetworkInfo
   return activeNetwork != null && activeNetwork.isConnected
}

Answer 11

以下代码适用于所有API。（科特琳）

但是，仅在API 29中弃用了getActiveNetworkInfo（），并且只能在所有API上使用，因此我们可以在29以下的所有Api中使用它

fun isInternetAvailable(context: Context): Boolean {
            var result = false
            val connectivityManager =
                context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                val networkCapabilities = connectivityManager.activeNetwork ?: return false
                val actNw =
                    connectivityManager.getNetworkCapabilities(networkCapabilities) ?: return false
                result = when {
                    actNw.hasTransport(NetworkCapabilities.TRANSPORT_WIFI) -> true
                    actNw.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR) -> true
                    actNw.hasTransport(NetworkCapabilities.TRANSPORT_ETHERNET) -> true
                    else -> false
                }
            } else {
                connectivityManager.run {
                    connectivityManager.activeNetworkInfo?.run {
                        result = when (type) {
                            ConnectivityManager.TYPE_WIFI -> true
                            ConnectivityManager.TYPE_MOBILE -> true
                            ConnectivityManager.TYPE_ETHERNET -> true
                            else -> false
                        }

                    }
                }
            }

            return result
        }

Answer 12

NetManager ，您可以使用它在 Kotlin

上检查Android上的互联网连接

如果您使用 minSdkVersion> = 23

class NetManager @Inject constructor(var applicationContext: Context) {
    val isConnectedToInternet: Boolean?
        get() = with(
            applicationContext.getSystemService(Context.CONNECTIVITY_SERVICE)
                    as ConnectivityManager
        ) {
            isConnectedToInternet()
        }
}

fun ConnectivityManager.isConnectedToInternet() = isConnected(getNetworkCapabilities(activeNetwork))

fun isConnected(networkCapabilities: NetworkCapabilities?): Boolean {
    return when (networkCapabilities) {
        null -> false
        else -> with(networkCapabilities) { hasTransport(TRANSPORT_CELLULAR) || hasTransport(TRANSPORT_WIFI) }
    }
}

如果您使用 minSdkVersion <23

class NetManager @Inject constructor(var applicationContext: Context) {
    val isConnectedToInternet: Boolean?
        get() = with(
            applicationContext.getSystemService(Context.CONNECTIVITY_SERVICE)
                    as ConnectivityManager
        ) {
            isConnectedToInternet()
        }
}

fun ConnectivityManager.isConnectedToInternet(): Boolean = if (Build.VERSION.SDK_INT < 23) {
    isConnected(activeNetworkInfo)
} else {
    isConnected(getNetworkCapabilities(activeNetwork))
}


fun isConnected(network: NetworkInfo?): Boolean {
    return when (network) {
        null -> false
        else -> with(network) { isConnected && (type == TYPE_WIFI || type == TYPE_MOBILE) }
    }
}

fun isConnected(networkCapabilities: NetworkCapabilities?): Boolean {
    return when (networkCapabilities) {
        null -> false
        else -> with(networkCapabilities) { hasTransport(TRANSPORT_CELLULAR) || hasTransport(TRANSPORT_WIFI) }
    }
}

Answer 13

检查可用的互联网

    @RequiresPermission(allOf = [Manifest.permission.ACCESS_NETWORK_STATE, Manifest.permission.INTERNET])
    fun isInternetAvailable(context: Context): Boolean {
    val connectivityManager = context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager?
    val activeNetworkInfo = connectivityManager!!.activeNetworkInfo
    return activeNetworkInfo != null && activeNetworkInfo.isConnected
}

Answer 14

我们可能需要多次检查互联网连接。因此，如果我们以Context的扩展方法编写代码块，对我们来说将更加容易。以下是我对Context和Fragment的帮助扩展。

检查Internet连接

fun Context.hasInternet(): Boolean {
    val connectivityManager = getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
    return if (Build.VERSION.SDK_INT < 23) {
        val activeNetworkInfo = connectivityManager.activeNetworkInfo
        activeNetworkInfo != null && activeNetworkInfo.isConnected
    } else {
        val nc = connectivityManager.getNetworkCapabilities(connectivityManager.activeNetwork)
        if (nc == null) {
            false
        } else {
            nc.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR) ||
                    nc.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)
        }
    }
}

其他扩展名

fun Context.hasInternet(notifyNoInternet: Boolean = true, trueFunc: (internet: Boolean) -> Unit) {
    if (hasInternet()) {
        trueFunc(true)
    } else if (notifyNoInternet) {
        Toast.makeText(this, "No Internet Connection!", Toast.LENGTH_SHORT).show()
    }
}

fun Context.hasInternet(
    trueFunc: (internet: Boolean) -> Unit,
    falseFunc: (internet: Boolean) -> Unit
) {
    if (hasInternet()) {
        trueFunc(true)
    } else {
        falseFunc(true)
    }
}

fun Fragment.hasInternet(): Boolean = context!!.hasInternet()

fun Fragment.hasInternet(notifyNoInternet: Boolean = true, trueFunc: (internet: Boolean) -> Unit) =
    context!!.hasInternet(notifyNoInternet, trueFunc)

fun Fragment.hasInternet(
    trueFunc: (internet: Boolean) -> Unit, falseFunc: (internet: Boolean) -> Unit
) = context!!.hasInternet(trueFunc, falseFunc)

Answer 15

https://www.agnosticdev.com/content/how-detect-network-connectivity-android

请遵循本教程，它应该可以帮助任何寻求答案的人。

注意networkInfo已被弃用，因此将其替换为isNetworkReacheable（）以下是@vidha答案将getApplicationContext（）作为参数传递

  public static boolean isNetworkReacheable(Context context) {
    boolean result = false;
    ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        if (cm != null) {
            NetworkCapabilities capabilities = cm.getNetworkCapabilities(cm.getActiveNetwork());
            if (capabilities != null) {
                if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
                    result = true;
                } else if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
                    result = true;
                }
            }
        }
    } else {
        if (cm != null) {
            NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
            if (activeNetwork != null) {
                // connected to the internet
                if (activeNetwork.getType() == ConnectivityManager.TYPE_WIFI) {
                    result = true;
                } else if (activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE) {
                    result = true;
                }
            }
        }
    }
    return result;
}

Answer 16

类似这样的东西：

public boolean hasConnection(final Context context){
    ConnectivityManager cm = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo activeNW = cm.getActiveNetworkInfo();
    if (activeNW != null && activeNW.isConnected())
    {
        return true;
    }
    return false;
}

在程序主体中：

if(hasConnection(this)) {
    Toast.makeText(this, "Active networks OK ", Toast.LENGTH_LONG).show();
    getAccountData(token, tel);
}
else  Toast.makeText(this, "No active networks... ", Toast.LENGTH_LONG).show();

Answer 17

这也将在Android 10中运行。如果连接到互联网，它将返回true，否则返回false。

private fun isOnline(): Boolean {
        val connectivityManager =
                getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
        val capabilities =
                connectivityManager.getNetworkCapabilities(connectivityManager.activeNetwork)
        if (capabilities != null) {
            when {
                capabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR) -> {
                    Log.i("Internet", "NetworkCapabilities.TRANSPORT_CELLULAR")
                    return true
                }
                capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI) -> {
                    Log.i("Internet", "NetworkCapabilities.TRANSPORT_WIFI")
                    return true
                }
                capabilities.hasTransport(NetworkCapabilities.TRANSPORT_ETHERNET) -> {
                    Log.i("Internet", "NetworkCapabilities.TRANSPORT_ETHERNET")
                    return true
                }
            }
        }
        return false
    }

Answer 18

版本28中弃用了可接受的答案，因此这是我在项目中使用的解决方案。

返回连接类型。 false：没有Internet连接；真实：移动数据|| wifi

public static boolean isNetworkConnected(Context context) { 
            boolean result = false; 
            ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                if (cm != null) {
                    NetworkCapabilities capabilities = cm.getNetworkCapabilities(cm.getActiveNetwork());
                    if (capabilities != null) {
                        if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
                            result = true;
                        } else if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
                            result = true;
                        }
                    }
                }
            } else {
                if (cm != null) {
                    NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
                    if (activeNetwork != null) {
                        // connected to the internet
                        if (activeNetwork.getType() == ConnectivityManager.TYPE_WIFI) {
                            result = true;
                        } else if (activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE) {
                            result = true;
                        }
                    }
                }
            }
            return result;
        }

Answer 19

使用 目标sdk 29 检查网络状态：

process_event_b

Answer 20

这在Kotlin对我有用。 Network Manager类中不推荐使用许多API，因此下面的答案涵盖了所有API支持。

fun isNetworkAvailable(context: Context): Boolean {
    var result = false
    (context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager).apply {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                result = isCapableNetwork(this,this.activeNetwork)
            } else {
                val networkInfos = this.allNetworks
                for (tempNetworkInfo in networkInfos) {
                    if(isCapableNetwork(this,tempNetworkInfo))
                        result =  true
                }
            }
        }

    return result
}

fun isCapableNetwork(cm: ConnectivityManager,network: Network?): Boolean{
     cm.getNetworkCapabilities(network)?.also {
        if (it.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)) {
            return true
        } else if (it.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)) {
            return true
        }
    }
    return false
}

您还将在下面添加

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Answer 21

在Android M（API 28）以下找不到

connectivityManager.getActiveNetwork（）。在Android L上方不推荐使用networkInfo.getState（）。

所以，最后的答案是：

public static boolean isConnectingToInternet(Context mContext) {
    if (mContext == null) return false;

    ConnectivityManager connectivityManager = (ConnectivityManager) mContext.getSystemService(Context.CONNECTIVITY_SERVICE);
    if (connectivityManager != null) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            final Network network = connectivityManager.getActiveNetwork();
            if (network != null) {
                final NetworkCapabilities nc = connectivityManager.getNetworkCapabilities(network);

                return (nc.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR) ||
                        nc.hasTransport(NetworkCapabilities.TRANSPORT_WIFI));
            }
        } else {
            NetworkInfo[] networkInfos = connectivityManager.getAllNetworkInfo();
            for (NetworkInfo tempNetworkInfo : networkInfos) {
                if (tempNetworkInfo.isConnected()) {
                    return true;
                }
            }
        }
    }
    return false;
}

Answer 22

public boolean isConnectedToWifi(Context context) {
    ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
    if (connectivityManager == null) {
        return false;
    }

    if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {
        Network network = connectivityManager.getActiveNetwork();
        NetworkCapabilities capabilities = connectivityManager.getNetworkCapabilities(network);
        if (capabilities == null) {
            return false;
        }
        return capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI);
    } else {
        NetworkInfo networkInfo = connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
        if (networkInfo == null) {
            return false;
        }
        return networkInfo.isConnected();
    }
}

Answer 23

最好检查您的网络是否连接到Internet：

@Suppress("DEPRECATION")
fun isNetworkAvailable(context: Context): Boolean {
    try {
        val cm = context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
        return if (Build.VERSION.SDK_INT > 22) {
            val an = cm.activeNetwork ?: return false
            val capabilities = cm.getNetworkCapabilities(an) ?: return false
            capabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)
        } else {
            val a = cm.activeNetworkInfo ?: return false
            a.isConnected && (a.type == ConnectivityManager.TYPE_WIFI || a.type == ConnectivityManager.TYPE_MOBILE)
        }
    } catch (e: Exception) {
        e.printStackTrace()
    }
    return false
}

Answer 24

（几乎）所有答案均已在Android P中弃用，因此这里是C#解决方案（对于Java开发人员来说，易于理解）

public bool IsOnline(Context context)
{
    var cm = (ConnectivityManager)context.GetSystemService(Context.ConnectivityService);

    if (cm == null) return false;

    if (Build.VERSION.SdkInt < BuildVersionCodes.M)
    {
        var ni = cm.ActiveNetworkInfo;

        if (ni == null) return false;

        return ni.IsConnected && (ni.Type == ConnectivityType.Wifi || ni.Type == ConnectivityType.Mobile);
    }

    return cm.GetNetworkCapabilities(cm.ActiveNetwork).HasTransport(Android.Net.TransportType.Wifi)
        || cm.GetNetworkCapabilities(cm.ActiveNetwork).HasTransport(Android.Net.TransportType.Cellular);
}

此处的密钥为Android.Net.TransportType

Answer 25

这是我检查当前网络是否在最新的Android版本上使用蜂窝网络的方法：

val isCellular: Boolean get() {
    val cm = getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager
    return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
        cm.getNetworkCapabilities(cm.activeNetwork).hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR)
    } else {
        cm.activeNetworkInfo?.type == ConnectivityManager.TYPE_MOBILE
    }
}

Answer 26

由于发布的答案仅允许您查询活动的网络，因此以下说明如何获取NetworkInfo的任何网络，而不仅是活动的网络（例如Wifi网络）（抱歉，前面的Kotlin代码）

(getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager).run {
    allNetworks.find { getNetworkInfo(it).type == ConnectivityManager.TYPE_WIFI }?.let { network -> getNetworkInfo(network) }
//    getNetworkInfo(ConnectivityManager.TYPE_WIFI).isAvailable // This is the deprecated API pre-21
}

这需要API 21或更高版本以及权限android.permission.ACCESS_NETWORK_STATE

不推荐使用ConnectivityManager getNetworkInfo（int）

26 个答案:

整个方法如下：