android how to get indicate when the internet connection is lost?

Question

I'm developing an android application and I want to get a notification when the internet (wifi or packet data connection) connection is lost. On my approach I can get the status of the connection as:

private boolean isNetworkAvailable() {
ConnectivityManager connectivityManager 
      = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
return activeNetworkInfo != null && activeNetworkInfo.isConnected();
}

while having this in the Manifest:

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

How could I be notified automatically when the connection is lost?

The above code is the standard way to check whether there is internet or not, so what is your question? — Scary Wombat, Jan 20 '14 at 05:28
see here http://stackoverflow.com/questions/3119607/how-to-be-notified-on-wifi-network-status-change — Gopal Gopi, Jan 20 '14 at 05:29
@user2310289 : its need to call the `isNetworkAvailable();` method to get to know the connection status. its ok when app starting. but while app running its not much good way to handle the requirement — Dinithe Pieris, Jan 20 '14 at 05:34

gunar · Accepted Answer · 2014-01-20T05:43:48.243

10

For WIFI you could register a broadcast receiver as:

IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(WifiManager.SUPPLICANT_CONNECTION_CHANGE_ACTION);
registerReceiver(broadcastReceiver, intentFilter);

You can also register the receiver in the Manifest.

Then in your receiver:

@Override
public void onReceive(Context context, Intent intent) {
    final String action = intent.getAction();
    if (action.equals(WifiManager.SUPPLICANT_CONNECTION_CHANGE_ACTION)) {
        if (intent.getBooleanExtra(WifiManager.EXTRA_SUPPLICANT_CONNECTED, false)){
            //do stuff
        } else {
            // wifi connection was lost
        }
    }
}

For any type of data connection listeners you could use the following receiver registered as:

<receiver android:name=".receiver.ConnectivityReceiver">
    <intent-filter>
        <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
        <action android:name="android.net.wifi.WIFI_STATE_CHANGED" />
    </intent-filter>
</receiver>

and the in your ConnectivityReceiver:

public class ConnectivityReceiver extends BroadcastReceiver {

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

In the onReceive method you could check if you have internet connectivity or not using this developer article.

edited Jan 20 '14 at 05:43

answered Jan 20 '14 at 05:27

gunar

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could you please explain `registerReceiver(broadcastReceiver, intentFilter);` – Dinithe Pieris Jan 20 '14 at 06:04
You can use `registerReceiver` if you're interested to be notified on the life-time of an `Activity`/`Service`. Otherwise you're registering a `BroadcastReceiver` directly in the manifest and so you're getting the updates all the time, no matter if the application is running or not. [`registerReceiver`](http://developer.android.com/reference/android/content/Context.html#registerReceiver(android.content.BroadcastReceiver, android.content.IntentFilter)) is available in the `Context` class. Just don't forget to call unregisterReceiver if you registered in a `Context` class. – gunar Jan 20 '14 at 06:18
does this also work when mobile data connection is lost? – emilpmp Dec 13 '17 at 05:42
This intent action/constant was deprecated in API level 28. – Sundeep1501 Oct 02 '18 at 07:44

Shayan Pourvatan · Answer 2 · 2014-01-20T05:44:50.703

use following code:

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import classes.NetworkUtil;

public class NetworkChangeReceiver extends BroadcastReceiver {

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

            boolean IsConnected = NetworkUtil.getConnectivityStatusString(context);
           // Toast in here, you can retrieve other value like String from NetworkUtil
           // but you need some change in NetworkUtil Class
        }
    }

and NetworkUtil is:

package classes;

import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;

public class NetworkUtil {

    public static int TYPE_WIFI = 1;
    public static int TYPE_MOBILE = 2;
    public static int TYPE_NOT_CONNECTED = 0;


    public static int getConnectivityStatus(Context context) {
        ConnectivityManager cm = (ConnectivityManager) context
                .getSystemService(Context.CONNECTIVITY_SERVICE);

        NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
        if (null != activeNetwork) {
            if(activeNetwork.getType() == ConnectivityManager.TYPE_WIFI)
                return TYPE_WIFI;

            if(activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE)
                return TYPE_MOBILE;
        } 
        return TYPE_NOT_CONNECTED;
    }

    public static boolean getConnectivityStatusString(Context context) {
        int conn = NetworkUtil.getConnectivityStatus(context);
        boolean status = false ;
        if (conn == NetworkUtil.TYPE_WIFI) {
            status = true;
        } else if (conn == NetworkUtil.TYPE_MOBILE) {
            status = true; 
        } else if (conn == NetworkUtil.TYPE_NOT_CONNECTED) {
            status = false;
        }
        return status;
    }
}

and in manifest file:

 <receiver
            android:name="receiver.NetworkChangeReceiver" >
            <intent-filter>
                <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
            </intent-filter>
        </receiver>

and this permission:

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

This is deprecated for apps targeting N and higher. In general, apps should not rely on this broadcast and instead use JobScheduler. — c-an, Jun 21 '19 at 08:30
Yes you right, you must use JobScheduler, WorkManager, or register broadcast programmatically @c-an, I wrote this answer in 2014 — Shayan Pourvatan, Jun 22 '19 at 07:31

score 0 · Answer 3 · answered Jan 20 '14 at 05:28

You need to set up a broadcast receiver.

Add these as intent filters.

            <intent-filter>
                <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
                <action android:name="android.net.wifi.WIFI_STATE_CHANGED" />
            </intent-filter>

score -3 · Answer 4 · edited Jun 20 '20 at 09:12

-3

You should use BroadcastReceivers for your requirement. Create a BroadcastReceiver which listen for network changes.

Incase of any change in the network it will automatically fire the event and you can perform your operations regarding it.

edited Jun 20 '20 at 09:12

Community

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answered Jan 20 '14 at 05:27

Kitkat

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android how to get indicate when the internet connection is lost?

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