Android Check Internet Connection mediante Broadcast
Me gustaría implementar un receptor de difusión para mi comprobación de conexión a Internet. Si la conexión no está presente acaba de terminar (); eso. Pero todavía estoy estropeando el contexto. Compruebe por favor en mis códigos abajo.
/** * This broadcast receiver is awoken after boot and registers the service that * checks for new photos from all the known contacts. */ public class ConnectionDetector extends BroadcastReceiver { @Override public void onReceive(Context context, Intent intent) { boolean noConnectivity = intent.getBooleanExtra(ConnectivityManager.EXTRA_NO_CONNECTIVITY,false); if(noConnectivity){ ((Activity)context).finish(); //Show Warning Message //Close Application the way i suggested } } } AndroidManifest
<receiver android:name=".ConnectionDetector" android:label="NetworkConnection"> <intent-filter> <action android:name="android.net.conn.CONNECTIVITY_CHANGE"/> </intent-filter> </receiver>
LogCat:
11-01 22:40:29.179: E/AndroidRuntime(29531): FATAL EXCEPTION: main 11-01 22:40:29.179: E/AndroidRuntime(29531): java.lang.RuntimeException: Unable to start receiver in.wptrafficanalyzer.actionbarsherlocknavtab.ConnectionDetector: java.lang.ClassCastException: android.app.ReceiverRestrictedContext 11-01 22:40:29.179: E/AndroidRuntime(29531): at android.app.ActivityThread.handleReceiver(ActivityThread.java:1809) 11-01 22:40:29.179: E/AndroidRuntime(29531): at android.app.ActivityThread.access$2400(ActivityThread.java:117) 11-01 22:40:29.179: E/AndroidRuntime(29531): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:985) 11-01 22:40:29.179: E/AndroidRuntime(29531): at android.os.Handler.dispatchMessage(Handler.java:99) 11-01 22:40:29.179: E/AndroidRuntime(29531): at android.os.Looper.loop(Looper.java:130) 11-01 22:40:29.179: E/AndroidRuntime(29531): at android.app.ActivityThread.main(ActivityThread.java:3691) 11-01 22:40:29.179: E/AndroidRuntime(29531): at java.lang.reflect.Method.invokeNative(Native Method) 11-01 22:40:29.179: E/AndroidRuntime(29531): at java.lang.reflect.Method.invoke(Method.java:507) 11-01 22:40:29.179: E/AndroidRuntime(29531): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:907) 11-01 22:40:29.179: E/AndroidRuntime(29531): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:665) 11-01 22:40:29.179: E/AndroidRuntime(29531): at dalvik.system.NativeStart.main(Native Method) 11-01 22:40:29.179: E/AndroidRuntime(29531): Caused by: java.lang.ClassCastException: android.app.ReceiverRestrictedContext 11-01 22:40:29.179: E/AndroidRuntime(29531): at in.wptrafficanalyzer.actionbarsherlocknavtab.ConnectionDetector.onReceive(ConnectionDetector.java:29) 11-01 22:40:29.179: E/AndroidRuntime(29531): at android.app.ActivityThread.handleReceiver(ActivityThread.java:1798) 11-01 22:40:29.179: E/AndroidRuntime(29531): ... 10 more
El contexto que se obtiene en BroadcastReciever no es una actividad. BroadcastReciever trabaja fuera de la actividad y no está vinculado a uno, a menos que lo haga específicamente.
Dejando de lado la mala práctica de acabar la actividad en el problema de Internet sin notificar al usuario puede hacer lo siguiente:
public abstract class ConnectionAwareActivity extends Activity { protected final IntentFilter mIntentFilter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION); // A filter for a BR. We want to listen to internet changes protected final ConnectionDetector mConnectionDetector = new ConnectionDetector(); // Creating an instance of our BR for activity to use @Override protected void onResume() { super.onResume(); try { registerReceiver(mConnectionDetector, mIntentFilter); // Activity gets shown, we register a BR and it starts to receive notifications about internet changes } catch (Exception exc) { // whoops } } @Override protected void onPause() { super.onPause(); try { unregisterReceiver(mConnectionDetector); // Try to unregister BR, since when activity is not visible to user, we don't want to perform any operations on internet change } catch (Exception exc) { // whoops } } // Your BR that is encapsulated in Activity and therefore has access to it's methods, since it has access to Activity instance protected class ConnectionDetector extends BroadcastReceiver { @Override public void onReceive(Context context, Intent intent) { boolean noConnectivity = intent.getBooleanExtra(ConnectivityManager.EXTRA_NO_CONNECTIVITY, false); if (noConnectivity) { finish(); } } }
}
Utilícelo como una superclase para sus otras actividades (esto se extiende de la actividad, lo cambia a lo que), que se debe terminar en errores de la conectividad.
Es una variante muy básica y un poco equivocada, ya que es mejor preferir la composición sobre superclases