Maurice Wohlkönig

public class UEService extends Service {
	private static final String TAG = "UEService";
	private Timer timer;
	private static final int delay = 1000; // delay for 1 sec before first start
	private static final int period = 10000; // repeat check every 10 sec.
 
	// This is the old onStart method that will be called on the pre-2.0
	// platform. On 2.0 or later we override onStartCommand() so this
	// method will not be called.
	@Override
	public void onStart(Intent intent, int startId) {
		handleCommand(intent);
	}
 
	// To make this Service work in pre Level 5 APIs just remove this method
	@Override
	public int onStartCommand(Intent intent, int flags, int startId) {
		handleCommand(intent);
		return START_NOT_STICKY;
	}
 
	// handles a Start command
	private void handleCommand(Intent intent) {
		Log.d(TAG, "service is starting");
 
		if (timer == null) {
			timer = new Timer();
			timer.schedule(new TimerTask() {
				public void run() {
					checkActivityForeground();
				}
			}, delay, period);
		}
	}
 
	protected void checkActivityForeground() {
		Log.d(TAG, "start checking for Activity in foreground");
		Intent intent = new Intent();
		intent.setAction(UESurveillanceActivity.UE_ACTION);
		sendOrderedBroadcast(intent, null, new BroadcastReceiver() {
 
			@Override
			public void onReceive(Context context, Intent intent) {
				int result = getResultCode();
 
				if (result != Activity.RESULT_CANCELED) { // Activity caught it
					Log.d(TAG, "An activity caught the broadcast, result " + result);
					activityInForeground();
					return;
				}
				Log.d(TAG, "No activity did catch the broadcast.");
				noActivityInForeground();
			}
		}, null, Activity.RESULT_CANCELED, null, null);
	}
 
	protected void activityInForeground() {
		Log.d(TAG, "starting method which gets called when an SureveillanceActivity is in foreground");
 
		// TODO something you want to happen when an Activity is in the foreground		
	}
 
	protected void noActivityInForeground() {
		Log.d(TAG, "starting method which gets called when no SureveillanceActivity is in foreground");
 
		// TODO something you want to happen when no Activity is in the foreground
 
		stopSelf(); // quit
	}
 
	@Override
	public IBinder onBind(Intent arg0) {
		// TODO Auto-generated method stub
		return null;
	}
 
	@Override
	public void onDestroy() {
		super.onDestroy();
		timer.cancel();
		Log.d(TAG, "service is destroyed");
	}
}

public class UESurveillanceActivity extends Activity {
	public static final String UE_ACTION = "at.mannaz.surveilance.inforeground";
	private IntentFilter mIntentFilter;
 
	private BroadcastReceiver mIntentReceiver = new BroadcastReceiver() {
		@Override
		public void onReceive(Context context, Intent intent) {
			String action = intent.getAction();
			if(action.equals(UE_ACTION)) {
				Log.d("UESurveilanceActivity","i'm in the foreground");
				this.setResultCode(Activity.RESULT_OK);
			}		
		}
	};
 
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
 
		mIntentFilter = new IntentFilter();
		mIntentFilter.addAction(UE_ACTION);
 
		Intent serviceIntent = new Intent(this, UEService.class);
		startService(serviceIntent);
	}
 
	@Override
	protected void onResume() {
		registerReceiver(mIntentReceiver, mIntentFilter);
 
		super.onResume();
	}
 
	@Override
	protected void onPause() {
		unregisterReceiver(mIntentReceiver);
 
		super.onPause();
	}
}

public class Dashboard extends UESurveillanceActivity {
...