Listening to Internet changes (No Network Detection)

Question

Would registering the following listener notify your app when internet connectivity changes or only when network connectivity changes?

I need to get notified when the internet goes on or off even if the phone is still connected to the same network.

<receiver
        android:name="com.internetconnection_demo.InternetConnector_Receiver"
        android:enabled="true" >
        <intent-filter>

            <!-- Intent filters for broadcast receiver -->
            <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
            <action android:name="android.net.wifi.WIFI_STATE_CHANGED" />
            <action android:name="android.net.wifi.STATE_CHANGE" />
        </intent-filter>
    </receiver>

There's no public framework in Android that tracks internet connectivity. — TheWanderer, Dec 11 '18 at 19:53

rhpekarek · Answer 1 · 2018-12-11T20:10:07.873

0

If you are on Lollipop (API 21) or later, I wouldn't go the BroadcastReceiver route. Try something like this instead:

fun monitorWifiConnection() {
    var connectivityManager: ConnectivityManager = getSystemService(CONNECTIVITY_SERVICE) as ConnectivityManager
    val builder = NetworkRequest.Builder()
            .addTransportType(android.net.NetworkCapabilities.TRANSPORT_WIFI)
    connectivityManager.registerNetworkCallback(builder.build(), getConnectivityManagerCallback())
}

private fun getConnectivityManagerCallback(): ConnectivityManager.NetworkCallback {
    connectivityManagerCallback = object : ConnectivityManager.NetworkCallback() {
        override fun onAvailable(network: Network?) {
            //Connected to wifi
        }

        override fun onLost(network: Network?) {
            //Lost connection to wifi
        }
    }
    return connectivityManagerCallback
}

By excluding the NetworkCapabilities.TRANSPORT_CELLULAR option and including NetworkCapabilities.TRANSPORT_WIFI you should get notifications about the wifi connection exclusively.

edited Dec 11 '18 at 20:10

answered Dec 11 '18 at 20:05

rhpekarek

167
9

But would this trigger the callback on Internet on/off even if I'm still connected to the WIFI? – user1603602 Dec 11 '18 at 20:09
Do you mean the cellular network? See the last note I added below the code snippet. You can choose to monitor cellular network or wifi or both. This request only monitors the wifi. – rhpekarek Dec 11 '18 at 20:11
Let's say the following scenario happened. - I'm connected to my wifi at home. - I'm still connected to the wifi, but the wifi access point itself lost internet connectivity. Would the callback happen in this case? – user1603602 Dec 11 '18 at 20:31
Yes that's how it should function – rhpekarek Dec 11 '18 at 20:34
I think NET_CAPABILITY_VALIDATED flag might be required on top (only API 23+) cf. https://stackoverflow.com/a/41063539/93974 – nuKs Mar 05 '20 at 18:17

Listening to Internet changes (No Network Detection)

1 Answers1