Network listener Android

Question

I want to check when the network of phone in Android goes off. Can I capture that event?

I am not getting the proper API or any example which would explain the same. If anyone had done or any example links would be really helpful.

Answer 1

New java class:

public class ConnectionChangeReceiver extends BroadcastReceiver {   @Override   public void onReceive( Context context, Intent intent )   {     ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService( Context.CONNECTIVITY_SERVICE );     NetworkInfo activeNetInfo = connectivityManager.getActiveNetworkInfo();     NetworkInfo mobNetInfo = connectivityManager.getNetworkInfo(     ConnectivityManager.TYPE_MOBILE );     if ( activeNetInfo != null )     {       Toast.makeText( context, "Active Network Type : " + activeNetInfo.getTypeName(), Toast.LENGTH_SHORT ).show();     }     if( mobNetInfo != null )     {       Toast.makeText( context, "Mobile Network Type : " + mobNetInfo.getTypeName(), Toast.LENGTH_SHORT ).show();     }   } } 

New xml in your AndroidManifest.xml under the "manifest" element:

<!-- Needed to check when the network connection changes --> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/> 

New xml in your AndroidManifest.xml under the "application" element:

<receiver android:name="com.blackboard.androidtest.receiver.ConnectionChangeReceiver"           android:label="NetworkConnection">   <intent-filter>     <action android:name="android.net.conn.CONNECTIVITY_CHANGE"/>   </intent-filter> </receiver> 

Answer 2

I have been using a small setup to check the bandwidth for determining how to scale things, such as images.

Under the activity, in AndroidManifest:

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

In the activity where the checks are being performed:

boolean network; int bandwidth;  @Override public void onCreate(Bundle savedInstanceState) {     ...     network = isDataConnected();     bandwidth = isHighBandwidth();     registerReceiver(new BroadcastReceiver() {         public void onReceive(Context context, Intent intent) {             network = isDataConnected();             bandwidth = isHighBandwidth();         }     }, new IntentFilter("android.net.conn.CONNECTIVITY_CHANGE"));     ... } ... private boolean isDataConnected() {     try {         ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);         return cm.getActiveNetworkInfo().isConnectedOrConnecting();     } catch (Exception e) {         return false;     } }  private int isHighBandwidth() {     ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);     NetworkInfo info = cm.getActiveNetworkInfo();     if (info.getType() == ConnectivityManager.TYPE_WIFI) {         WifiManager wm = (WifiManager) getSystemService(Context.WIFI_SERVICE);         return wm.getConnectionInfo().getLinkSpeed();     } else if (info.getType() == ConnectivityManager.TYPE_MOBILE) {         TelephonyManager tm = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);         return tm.getNetworkType();     }     return 0; } 

An example usage would then be:

if (network) {     if (bandwidth > 16) {         // Code for large items     } else if (bandwidth <= 16 && bandwidth > 8) {         // Code for medium items     } else {         //Code for small items     } } else {     //Code for disconnected } 

It's not the prettiest, but it allows enough flexibility that I can change the bandwidth cutoff for items depending on what they are and my requirements for them.