How to get network state change on android?

Question

I have broadcast receiver for "CONNECTIVITY_CHANGE". When I print the extra using this:

intent.getExtras().toString() 

I can see that if I disable WIFI, I receive 2 network change.

1. WIFI DISCONNECTED
2. MOBILE CONNECTED

However, when I try to use

NetworkInfo networkInfo = intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);

It said, this API has been deprecated. After that, I tried to use this

int networkType = intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_TYPE);
NetworkInfo networkInfo = connectivityManager.getNetworkInfo(networkType);

However, getNetworkInfo also has been deprecated.

The only option they give me was using getActiveNetworkInfo or getActiveNetwork.

If I use that, I will get 2 broadcast which will give me same network info.

Is there a better way to handle network state in Android ?

EXTRA NOTE:

Thanks for quick reply, but I am not looking for a way to check if I have internet connection or not.

I need to know which network has been disconnected and connected. The network state change is what I am looking for.

Answer 1

Here is a simple code snippet that will help you identify what kind of internet connection a user has on her device.

First we need following permission in order to access network state. Add following permission to your AndroidManifest.xml file.

Permissions required to access network state:

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

Now check following utility class NetworkUtil. It has method getConnectivityStatus which returns an int constant depending on current network connection. If wifi is enabled, this method will return TYPE_WIFI. Similarly for mobile data network is returns TYPE_MOBILE. You got the idea!!

There is also method getConnectivityStatusString which returns current network state as a more readable string.

Create a class NetworkUtil.java and paste the following code:

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 String getConnectivityStatusString(Context context) {
        int conn = NetworkUtil.getConnectivityStatus(context);
        String status = null;
        if (conn == NetworkUtil.TYPE_WIFI) {
            status = "Wifi enabled";
        } else if (conn == NetworkUtil.TYPE_MOBILE) {
            status = "Mobile data enabled";
        } else if (conn == NetworkUtil.TYPE_NOT_CONNECTED) {
            status = "Not connected to Internet";
        }
        return status;
    }
}

You can use this utility class in your android app to check the network state of the device at any moment.

Broadcast Receiver to handle changes in Network state

You can easily handle the changes in network state by creating your own Broadcast Receiver. Following is a broadcast receiver class where we handle the changes in network.

Check onReceive() method. This method will be called when state of network changes. Here we are just creating a Toast message and displaying current network state. You can write your custom code in here to handle changes in connection state.

Create a class NetworkChangeReceiver.java and paste the following code:

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;

public class NetworkChangeReceiver extends BroadcastReceiver {

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

        String status = NetworkUtil.getConnectivityStatusString(context);

        Toast.makeText(context, status, Toast.LENGTH_LONG).show();
    }
}

Once we define our BroadcastReceiver, we need to define the same in AndroidMenifest.xml file. Add following to your manifest file.

<application  ...>
     ...
        <receiver
            android:name="YOUR PACKAGE NAME"
            android:label="NetworkChangeReceiver" >
            <intent-filter>
                <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
                <action android:name="android.net.wifi.WIFI_STATE_CHANGED" />
            </intent-filter>
        </receiver>
      ...
</application>

We defined our broadcast receiver class in manifest file. Also we defined two intent CONNECTIVITY_CHANGE and WIFI_STATE_CHANGED. Thus this will register our receiver for given intents. Whenever there is change in network state, android will fire these intents and our broadcast receiver will be called.

That's it Run Your Code.Hope this serves your purpose !!