public class NetworkChangeReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(final Context context, final Intent intent) {
        if (checkInternet(context)) {
            Toast.makeText(context, "Network Available Do operations", Toast.LENGTH_LONG).show();
        }
    }

    boolean checkInternet(Context context) {
        ServiceManager serviceManager = new ServiceManager(context);
        return serviceManager.isNetworkAvailable()
    }
}

ServiceManager.java

public class ServiceManager {

    Context context;

    public ServiceManager(Context base) {
        context = base;
    }

    public boolean isNetworkAvailable() {
        ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = cm.getActiveNetworkInfo();
        return networkInfo != null && networkInfo.isConnected();
    }
}

权限:

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

试试这个

public class ConnectionBroadcastReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {


    if (<Check internet connection available >) { 
        Toast.makeText(context, "connect to the internet", Toast.LENGTH_LONG).show();

        /*upload background upload service*/
        Intent serviceIntent = new Intent(context,<your service class>);
        context.startService(serviceIntent);


    }else{
        Toast.makeText(context, "Connection failed", Toast.LENGTH_LONG).show();

    }
    }
}

一旦互联网连接触发，这(BroadcastReciever)将被加载

CONNECTIVITY_ACTION文档:

针对Android 7.0 (API级别24)及以上的应用程序，如果它们在manifest中声明了广播接收器，则不会接收此广播。如果应用程序向context . registerreceiver()注册了BroadcastReceiver，并且该context仍然有效，那么应用程序仍然会接收广播。

到2022年，上述BroadcastReceiver方法都将失效。由于Android 7.0的限制，BroadcastReceiver方法将不再工作。检查互联网是否可用的最新和最简单的方法是使用以下代码。(Android 12测试)

val networkRequest = NetworkRequest.Builder()
        .addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET)
        .addTransportType(NetworkCapabilities.TRANSPORT_WIFI)
        .addTransportType(NetworkCapabilities.TRANSPORT_CELLULAR)
        .build()

private val networkCallback = object : ConnectivityManager.NetworkCallback() {
    // network is available for use
    override fun onAvailable(network: Network) {
        super.onAvailable(network)
    }

    // Network capabilities have changed for the network
    override fun onCapabilitiesChanged(
            network: Network,
            networkCapabilities: NetworkCapabilities
    ) {
        super.onCapabilitiesChanged(network, networkCapabilities)
        val unmetered = networkCapabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_NOT_METERED)
    }

    // lost network connection
    override fun onLost(network: Network) {
        super.onLost(network)
    }
}

val connectivityManager = getSystemService(ConnectivityManager::class.java) as ConnectivityManager
connectivityManager.requestNetwork(networkRequest, networkCallback

将这段代码放在一个函数中，并在activity/fragment的onCreate()中调用它。在onAvailable()和onLost()函数中，每当互联网连接或断开连接时，您都会收到通知。与此同时，您可以使用liveData或任何您喜欢的方式在其他活动/片段中广播这些更新。 官方文档链接:https://developer.android.com/training/monitoring-device-state/connectivity-status-type

添加权限:

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

创建Receiver以检查连接

public class NetworkChangeReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(final Context context, final Intent intent) {

        if(checkInternet(context))
        {
            Toast.makeText(context, "Network Available Do operations",Toast.LENGTH_LONG).show(); 
        }

    }

    boolean checkInternet(Context context) {
        ServiceManager serviceManager = new ServiceManager(context);
        if (serviceManager.isNetworkAvailable()) {
            return true;
        } else {
            return false;
        }
    }

}

ServiceManager.java

public class ServiceManager {

    Context context;

    public ServiceManager(Context base) {
        context = base;
    }

    public boolean isNetworkAvailable() {
        ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = cm.getActiveNetworkInfo();
        return networkInfo != null && networkInfo.isConnected();
    }
}

这里有一种适合活动、片段或上下文的方法。它也会自动注销，如果你做的活动/片段(在onDestroy)，如果你希望:

abstract class ConnectionBroadcastReceiver : BroadcastReceiver() {
    companion object {
        @JvmStatic
        fun registerWithoutAutoUnregister(context: Context, connectionBroadcastReceiver: ConnectionBroadcastReceiver) {
            context.registerReceiver(connectionBroadcastReceiver, IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION))
        }

        @JvmStatic
        fun registerToFragmentAndAutoUnregister(context: Context, fragment: Fragment, connectionBroadcastReceiver: ConnectionBroadcastReceiver) {
            val applicationContext = context.applicationContext
            registerWithoutAutoUnregister(applicationContext, connectionBroadcastReceiver)
            fragment.lifecycle.addObserver(object : LifecycleObserver {
                @OnLifecycleEvent(Lifecycle.Event.ON_DESTROY)
                fun onDestroy() {
                    applicationContext.unregisterReceiver(connectionBroadcastReceiver)
                }
            })
        }

        @JvmStatic
        fun registerToActivityAndAutoUnregister(activity: AppCompatActivity, connectionBroadcastReceiver: ConnectionBroadcastReceiver) {
            registerWithoutAutoUnregister(activity, connectionBroadcastReceiver)
            activity.lifecycle.addObserver(object : LifecycleObserver {
                @OnLifecycleEvent(Lifecycle.Event.ON_DESTROY)
                fun onDestroy() {
                    activity.unregisterReceiver(connectionBroadcastReceiver)
                }
            })
        }

        @JvmStatic
        fun hasInternetConnection(context: Context): Boolean {
            val info = (context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager).activeNetworkInfo
            return !(info == null || !info.isConnectedOrConnecting)
        }
    }

    override fun onReceive(context: Context, intent: Intent) {
        val hasConnection = !intent.getBooleanExtra(ConnectivityManager.EXTRA_NO_CONNECTIVITY, false)
//        Log.d("AppLog", "conenctivity changed. hasConnection? $hasConnection")
        onConnectionChanged(hasConnection)
    }

    abstract fun onConnectionChanged(hasConnection: Boolean)
}

在片段中的用法:

    ConnectionBroadcastReceiver.registerToFragmentAndAutoUnregister(activity!!, this, object : ConnectionBroadcastReceiver() {
        override fun onConnectionChanged(hasConnection: Boolean) {
            // Log.d("AppLog", "onConnectionChanged:" + hasConnection)
        }
    })