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private const val DEBUG_TAG = "NetworkStatusExample" ... val connMgr = getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager var isWifiConn: Boolean = false var isMobileConn: Boolean = false connMgr.allNetworks.forEach { network ->     connMgr.getNetworkInfo(network).apply {         if (type == ConnectivityManager.TYPE_WIFI) {             isWifiConn = isWifiConn or isConnected         }         if (type == ConnectivityManager.TYPE_MOBILE) {             isMobileConn = isMobileConn or isConnected         }     } } Log.d(DEBUG_TAG, "Wifi connected: $isWifiConn") Log.d(DEBUG_TAG, "Mobile connected: $isMobileConn")

private static final String DEBUG_TAG = "NetworkStatusExample"; ... ConnectivityManager connMgr =         (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); boolean isWifiConn = false; boolean isMobileConn = false; for (Network network : connMgr.getAllNetworks()) {     NetworkInfo networkInfo = connMgr.getNetworkInfo(network);     if (networkInfo.getType() == ConnectivityManager.TYPE_WIFI) {         isWifiConn |= networkInfo.isConnected();     }     if (networkInfo.getType() == ConnectivityManager.TYPE_MOBILE) {         isMobileConn |= networkInfo.isConnected();     } } Log.d(DEBUG_TAG, "Wifi connected: " + isWifiConn); Log.d(DEBUG_TAG, "Mobile connected: " + isMobileConn);

fun isOnline(): Boolean {     val connMgr = getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager     val networkInfo: NetworkInfo? = connMgr.activeNetworkInfo     return networkInfo?.isConnected == true }

public boolean isOnline() {     ConnectivityManager connMgr = (ConnectivityManager)             getSystemService(Context.CONNECTIVITY_SERVICE);     NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();     return (networkInfo != null && networkInfo.isConnected()); }

class SettingsActivity : PreferenceActivity(), OnSharedPreferenceChangeListener {      override fun onCreate(savedInstanceState: Bundle?) {         super.onCreate(savedInstanceState)          // Loads the XML preferences file         addPreferencesFromResource(R.xml.preferences)     }      override fun onResume() {         super.onResume()          // Registers a listener whenever a key changes         preferenceScreen?.sharedPreferences?.registerOnSharedPreferenceChangeListener(this)     }      override fun onPause() {         super.onPause()          // Unregisters the listener set in onResume().         // It's best practice to unregister listeners when your app isn't using them to cut down on         // unnecessary system overhead. You do this in onPause().         preferenceScreen?.sharedPreferences?.unregisterOnSharedPreferenceChangeListener(this)     }      // When the user changes the preferences selection,     // onSharedPreferenceChanged() restarts the main activity as a new     // task. Sets the refreshDisplay flag to "true" to indicate that     // the main activity should update its display.     // The main activity queries the PreferenceManager to get the latest settings.      override fun onSharedPreferenceChanged(sharedPreferences: SharedPreferences, key: String) {         // Sets refreshDisplay to true so that when the user returns to the main         // activity, the display refreshes to reflect the new settings.         NetworkActivity.refreshDisplay = true     } }

public class SettingsActivity extends PreferenceActivity implements OnSharedPreferenceChangeListener {      @Override     protected void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);          // Loads the XML preferences file         addPreferencesFromResource(R.xml.preferences);     }      @Override     protected void onResume() {         super.onResume();          // Registers a listener whenever a key changes         getPreferenceScreen().getSharedPreferences().registerOnSharedPreferenceChangeListener(this);     }      @Override     protected void onPause() {         super.onPause();         // Unregisters the listener set in onResume().        // It's best practice to unregister listeners when your app isn't using them to cut down on        // unnecessary system overhead. You do this in onPause().        getPreferenceScreen().getSharedPreferences().unregisterOnSharedPreferenceChangeListener(this);     }      // When the user changes the preferences selection,     // onSharedPreferenceChanged() restarts the main activity as a new     // task. Sets the refreshDisplay flag to "true" to indicate that     // the main activity should update its display.     // The main activity queries the PreferenceManager to get the latest settings.      @Override     public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {         // Sets refreshDisplay to true so that when the user returns to the main         // activity, the display refreshes to reflect the new settings.         NetworkActivity.refreshDisplay = true;     } }

class NetworkActivity : Activity() {      // The BroadcastReceiver that tracks network connectivity changes.     private lateinit var receiver: NetworkReceiver      public override fun onCreate(savedInstanceState: Bundle?) {         super.onCreate(savedInstanceState)          // Registers BroadcastReceiver to track network connection changes.         val filter = IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION)         receiver = NetworkReceiver()         this.registerReceiver(receiver, filter)     }      public override fun onDestroy() {         super.onDestroy()         // Unregisters BroadcastReceiver when app is destroyed.         this.unregisterReceiver(receiver)     }      // Refreshes the display if the network connection and the     // pref settings allow it.      public override fun onStart() {         super.onStart()          // Gets the user's network preference settings         val sharedPrefs = PreferenceManager.getDefaultSharedPreferences(this)          // Retrieves a string value for the preferences. The second parameter         // is the default value to use if a preference value is not found.         sPref = sharedPrefs.getString("listPref", "Wi-Fi")          updateConnectedFlags()          if (refreshDisplay) {             loadPage()         }     }      // Checks the network connection and sets the wifiConnected and mobileConnected     // variables accordingly.     fun updateConnectedFlags() {         val connMgr = getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager          val activeInfo: NetworkInfo? = connMgr.activeNetworkInfo         if (activeInfo?.isConnected == true) {             wifiConnected = activeInfo.type == ConnectivityManager.TYPE_WIFI             mobileConnected = activeInfo.type == ConnectivityManager.TYPE_MOBILE         } else {             wifiConnected = false             mobileConnected = false         }     }      // Uses AsyncTask subclass to download the XML feed from stackoverflow.com.     fun loadPage() {         if (sPref == ANY && (wifiConnected || mobileConnected) || sPref == WIFI && wifiConnected) {             // AsyncTask subclass             DownloadXmlTask().execute(URL)         } else {             showErrorPage()         }     }      companion object {          const val WIFI = "Wi-Fi"         const val ANY = "Any"         const val SO_URL = "http://stackoverflow.com/feeds/tag?tagnames=android&sort;=newest"          // Whether there is a Wi-Fi connection.         private var wifiConnected = false         // Whether there is a mobile connection.         private var mobileConnected = false         // Whether the display should be refreshed.         var refreshDisplay = true          // The user's current network preference setting.         var sPref: String? = null     } ...  }

public class NetworkActivity extends Activity {     public static final String WIFI = "Wi-Fi";     public static final String ANY = "Any";     private static final String URL = "http://stackoverflow.com/feeds/tag?tagnames=android&sort;=newest";      // Whether there is a Wi-Fi connection.     private static boolean wifiConnected = false;     // Whether there is a mobile connection.     private static boolean mobileConnected = false;     // Whether the display should be refreshed.     public static boolean refreshDisplay = true;      // The user's current network preference setting.     public static String sPref = null;      // The BroadcastReceiver that tracks network connectivity changes.     private NetworkReceiver receiver = new NetworkReceiver();      @Override     public void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);          // Registers BroadcastReceiver to track network connection changes.         IntentFilter filter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);         receiver = new NetworkReceiver();         this.registerReceiver(receiver, filter);     }      @Override     public void onDestroy() {         super.onDestroy();         // Unregisters BroadcastReceiver when app is destroyed.         if (receiver != null) {             this.unregisterReceiver(receiver);         }     }      // Refreshes the display if the network connection and the     // pref settings allow it.      @Override     public void onStart () {         super.onStart();          // Gets the user's network preference settings         SharedPreferences sharedPrefs = PreferenceManager.getDefaultSharedPreferences(this);          // Retrieves a string value for the preferences. The second parameter         // is the default value to use if a preference value is not found.         sPref = sharedPrefs.getString("listPref", "Wi-Fi");          updateConnectedFlags();          if(refreshDisplay){             loadPage();         }     }      // Checks the network connection and sets the wifiConnected and mobileConnected     // variables accordingly.     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;         }     }      // Uses AsyncTask subclass to download the XML feed from stackoverflow.com.     public void loadPage() {         if (((sPref.equals(ANY)) && (wifiConnected || mobileConnected))                 || ((sPref.equals(WIFI)) && (wifiConnected))) {             // AsyncTask subclass             new DownloadXmlTask().execute(URL);         } else {             showErrorPage();         }     } ...  }

class NetworkReceiver : BroadcastReceiver() {      override fun onReceive(context: Context, intent: Intent) {         val conn = context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager         val networkInfo: NetworkInfo? = conn.activeNetworkInfo          // Checks the user prefs and the network connection. Based on the result, decides whether         // to refresh the display or keep the current display.         // If the userpref is Wi-Fi only, checks to see if the device has a Wi-Fi connection.         if (WIFI == sPref && networkInfo?.type == ConnectivityManager.TYPE_WIFI) {             // If device has its Wi-Fi connection, sets refreshDisplay             // to true. This causes the display to be refreshed when the user             // returns to the app.             refreshDisplay = true             Toast.makeText(context, R.string.wifi_connected, Toast.LENGTH_SHORT).show()              // If the setting is ANY network and there is a network connection             // (which by process of elimination would be mobile), sets refreshDisplay to true.         } else if (ANY == sPref && networkInfo != null) {             refreshDisplay = true              // Otherwise, the app can't download content--either because there is no network             // connection (mobile or Wi-Fi), or because the pref setting is WIFI, and there             // is no Wi-Fi connection.             // Sets refreshDisplay to false.         } else {             refreshDisplay = false             Toast.makeText(context, R.string.lost_connection, Toast.LENGTH_SHORT).show()         }     } }

public class NetworkReceiver extends BroadcastReceiver {      @Override     public void onReceive(Context context, Intent intent) {         ConnectivityManager conn =  (ConnectivityManager)             context.getSystemService(Context.CONNECTIVITY_SERVICE);         NetworkInfo networkInfo = conn.getActiveNetworkInfo();          // Checks the user prefs and the network connection. Based on the result, decides whether         // to refresh the display or keep the current display.         // If the userpref is Wi-Fi only, checks to see if the device has a Wi-Fi connection.         if (WIFI.equals(sPref) && networkInfo != null             && networkInfo.getType() == ConnectivityManager.TYPE_WIFI) {             // If device has its Wi-Fi connection, sets refreshDisplay             // to true. This causes the display to be refreshed when the user             // returns to the app.             refreshDisplay = true;             Toast.makeText(context, R.string.wifi_connected, Toast.LENGTH_SHORT).show();          // If the setting is ANY network and there is a network connection         // (which by process of elimination would be mobile), sets refreshDisplay to true.         } else if (ANY.equals(sPref) && networkInfo != null) {             refreshDisplay = true;          // Otherwise, the app can't download content--either because there is no network         // connection (mobile or Wi-Fi), or because the pref setting is WIFI, and there         // is no Wi-Fi connection.         // Sets refreshDisplay to false.         } else {             refreshDisplay = false;             Toast.makeText(context, R.string.lost_connection, Toast.LENGTH_SHORT).show();         }     } }