Répondre aux changements de préférences

Bonjour
Voici un exemple qui permet de répondre aux changements de préférences sous Android:
public class NetworkActivity extends Activity {
public static final String WIFI = "Wi-Fi";
public static final String ANY = "Any";
private static final String URL = "http://oyant.com/feeds/tag/...";

private static boolean wifiConnected = false;

private static boolean mobileConnected = false;

public static boolean refreshDisplay = true;

public static String sPref = null;

private NetworkReceiver receiver = new NetworkReceiver();

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

IntentFilter filter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
receiver = new NetworkReceiver();
this.registerReceiver(receiver, filter);
}

@Override
public void onDestroy() {
super.onDestroy();
if (receiver != null) {
this.unregisterReceiver(receiver);
}
}


@Override
public void onStart () {
super.onStart();

SharedPreferences sharedPrefs = PreferenceManager.getDefaultSharedPreferences(this);

sPref = sharedPrefs.getString("listPref", "Wi-Fi");

updateConnectedFlags();

if(refreshDisplay){
loadPage();
}
}


public void updateConnectedFlags() {
ConnectivityManager connMgr = (ConnectivityManager)
getSystemService(Context.CONNECTIVITY_SERVICE);

NetworkInfo activeInfo = connMgr.getActiveNetworkInfo();
if (activeInfo != null && activeInfo.isConnected()) {
wifiConnected = activeInfo.getType() == ConnectivityManager.TYPE_WIFI;
mobileConnected = activeInfo.getType() == ConnectivityManager.TYPE_MOBILE;
} else {
wifiConnected = false;
mobileConnected = false;
}
}

public void loadPage() {
if (((sPref.equals(ANY)) && (wifiConnected || mobileConnected))
|| ((sPref.equals(WIFI)) && (wifiConnected))) {

new DownloadXmlTask().execute(URL);
} else {
showErrorPage();
}
}
...

}