Develop Reference

Unable to clear mock location?

This is how I set a mock location in my app:
public void startMockLocation(String latitude, String longitude){
FusedLocationProviderClient locationProvider = new FusedLocationProviderClient(getApplicationContext());
locationProvider.setMockMode(true);
Location loc = new Location("gps");
mockLocation = new Location("gps");
mockLocation.setLatitude(Double.valueOf(latitude));
mockLocation.setLongitude(Double.valueOf(longitude));
mockLocation.setAltitude(loc.getAltitude());
mockLocation.setTime(System.currentTimeMillis());
mockLocation.setAccuracy(1f);
mockLocation.setElapsedRealtimeNanos(SystemClock.elapsedRealtimeNanos());
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
mockLocation.setBearingAccuracyDegrees(0.1f);
mockLocation.setVerticalAccuracyMeters(0.1f);
mockLocation.setSpeedAccuracyMetersPerSecond(0.01f);
}
locationProvider.setMockLocation(mockLocation);
}
However I wasn't able to clear the mock location and set the real location back using this code below. What should I write instead?
public void clearMockLocation() {
locationProvider.setMockMode(false);
}

as i see your code , you are calling two methods one to set mock location and other to disable it but in other method i am not sure which object of location provider you are using , i would prefer you to declare a global object of location provider and use it anywhere
FusedLocationProviderClient locationProvider;
public void startMockLocation(String latitude, String longitude){
locationProvider = new FusedLocationProviderClient(getApplicationContext());
locationProvider.setMockMode(true);
Location loc = new Location("gps");
mockLocation = new Location("gps");
mockLocation.setLatitude(Double.valueOf(latitude));
mockLocation.setLongitude(Double.valueOf(longitude));
mockLocation.setAltitude(loc.getAltitude());
mockLocation.setTime(System.currentTimeMillis());
mockLocation.setAccuracy(1f);
mockLocation.setElapsedRealtimeNanos(SystemClock.elapsedRealtimeNanos());
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
mockLocation.setBearingAccuracyDegrees(0.1f);
mockLocation.setVerticalAccuracyMeters(0.1f);
mockLocation.setSpeedAccuracyMetersPerSecond(0.01f);
}
locationProvider.setMockLocation(mockLocation);
}
then in other method
public void clearMockLocation() {
if(locationProvider!=null){
locationProvider.setMockMode(false);
if(mockLocation!=null){
mockLocation.setLatitude(real_latitude);
mockLocation.setLongitude(real_longitude);
mockLocation.setAltitude(real_altitude);
mockLocation.setTime(System.currentTimeMillis());
mockLocation.setAccuracy(1f);
mockLocation.setElapsedRealtimeNanos(SystemClock.elapsedRealtimeNanos());
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
mockLocation.setBearingAccuracyDegrees(0.1f);
mockLocation.setVerticalAccuracyMeters(0.1f);
mockLocation.setSpeedAccuracyMetersPerSecond(0.01f);
}
locationProvider.setMockLocation(mockLocation);
}
}
}

Update:
As far, your problem is following these steps such as:
Setting your mock location for Gps
Going to GoogleMaps and see your mock location
Turn back your app and want to stop mocking
Here I am giving you some techniques to disable mock locations.
Method.1
Spoofing or faked locations can be avoided by using the Location Manager's API.
For this you first have to import the google play services LocationServices (must visit) API:
You need to import:
import com.google.android.gms.location.LocationServices;
And in App-level build.gradle:
implementation 'com.google.android.gms:play-services-location:17.0.0'
Your Class must implement these interfaces:
public class TestMapsActivity extends FragmentActivity implements OnMapReadyCallback,
LocationListener,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener { ...}
Then, you need to Override these methods such as:
#Override
public void onConnected(Bundle bundle) {
}
#Override
public void onConnectionSuspended(int i) {
}
#Override
public void onConnectionFailed(ConnectionResult connectionResult) {
}
#Override
public void onLocationChanged(Location location) {
}
Now, We can remove the test provider before requesting the location updates from both the providers (Network or Gps):
LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
try {
Log.d(TAG ,"Removing Test providers")
locationManager .removeTestProvider(LocationManager.GPS_PROVIDER);
} catch (IllegalArgumentException error) {
Log.d(TAG,"Got exception in removing test provider");
}
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000, 0, locationListener);
Now, If you look into the Android documentation of the LocationManager:
removeTestProvider() throws
IllegalArgumentException if no provider with the given name exists
You will get a better intuition from this android-issue. For that specific thread, You can try using Criteria.ACCURACY_FINE instead of LocationManager.GPS_PROVIDER such as:
LocationManager locationManager = (LocationManager)context.getSystemService( Context.LOCATION_SERVICE );
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
String locationprovider = locationManager.getBestProvider(criteria, true);
if ( locationprovider == null ) {
Log.e(TAG, "location provider is not available.!");
return;
}
Method.2
If the above method still doesn't work for you, you can silently enable /disable mock settings as follows:
// disable mocking.
Settings.Secure.putString(getContentResolver(),
Settings.Secure.ALLOW_MOCK_LOCATION, "0");
You can also get better intuition here and here.
Method.3
There is another way you can do that to get an accurate understanding whether GPS/Network providers are enabled or not:
ContentResolver contentResolver = context.getContentResolver();
boolean gpsEnabled = Settings.Secure.isLocationProviderEnabled(contentResolver, LocationManager.GPS_PROVIDER);
boolean networkEnabled = Settings.Secure.isLocationProviderEnabled(contentResolver, LocationManager.NETWORK_PROVIDER);
Other Steps to follow.
You should have to follow these steps to clear/reset your mock location such as:
Enable mock locations in the development panel in your settings.
Add permissions to your Manifest.xml i.e.
<uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION" />
Now again open GoogleMaps, and wait until the Gps provider to receive a new realtime-location. It could be a bit of time-consuming i.e. (1-3 minutes).
So while removing the provider, just let the Gps receive a new fresh location, then it will be resolved and fixed. If in case, it is not working again, then you can further do these steps:
Go to the app settings, Clear the App-Cache and Restart the Mobile
Device.
I hope that it would work really fine. You can also visit these references to get better intuition:
Android-mock-location-on-device
Remove-mock-location

How to call fusedLocationClient.getLastLocation() from within a JobService?

I'm trying to implement getLastLocation().addOnSuccessListener as documented here: https://developer.android.com/training/location/retrieve-current#last-known but in my case within a JobService which is periodically ran by the JobScheduler.
Here is the meaningful part of my jobService:
public class PeriodicJob extends JobService {
final String TAG = "BNA.Job";
private FusedLocationProviderClient fusedLocationClient;
#Override
public void onCreate() {
super.onCreate();
fusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
Log.i(TAG, "onCreate");
}
#Override
public boolean onStartJob(JobParameters params) {
Log.d(TAG, "Job started..."); // logs every 15mins
fusedLocationClient.getLastLocation()
.addOnSuccessListener(this, new OnSuccessListener<Location>() {
#Override
public void onSuccess(Location location) {
// Got last known location. In some rare situations this can be null.
if (location != null) {
Log.d(TAG, "got Location: " + location);
Log.d(TAG, "Accuracy:" + location.getAccuracy()+", LON:"
+location.getLongitude() + ", LAT:" + location.getLatitude());
}
}
})
.addOnFailureListener(new OnFailureListener() {
#Override
(...) // never runs
});
return true;
}
When I run this (it compiles fine), I get: Caused by: java.lang.ClassCastException: (...)PeriodicJob cannot be cast to java.util.concurrent.Executor
I looked at Android app crashes on firebase phone authentication and Can't cast this into Executor in google reCAPTCHA but I still couldnt get it working. Just calling .addOnSuccessListener(new OnSuccessListener<Location>() like the second question's answer suggests, throws no error, but the code is never executed (at least, no log is written).
How can I get the call to onSuccess working?
EDIT: In fact it was working all the time (without the first parameter), I had neglected to detect the case when a null location was returned (which I wasnt expecting). Thanks to Mike M.!

How to make activity to show data got from the service?

I need write a service which will update the list in MainActivity every 30sec. I use MVVM with ViewModel and LiveData and so my Service class looks like this:
public class ArticleJobService extends JobService {
public static String TAG = "ArticleJobService";
private Context context = this;
#Override
public boolean onStartJob(JobParameters jobParameters) {
Log.d(TAG, "onStartJob");
MainActivity.PAGE_NUMBER++;
LiveData<List<Article>> liveArticles = ArticleRepository.getInstance(getApplication()).getArticles(MainActivity.PAGE_NUMBER);
liveArticles.observeForever(new Observer<List<Article>>() {
#Override
public void onChanged(#Nullable List<Article> articles) {
Log.d(TAG, "onStartJob - onChanged!!!!!!");
liveArticles.removeObserver(this);
NotificationUtils.showNotification(context, articles.get(0).getSectionName(), articles.get(0).getWebTitle());
jobFinished(jobParameters, true);
}
});
return true;
}
}
Class for my notification:
public static void showNotification(Context context, String section, String title) {
PendingIntent contentPendingIntent = PendingIntent.getActivity
(context, REQUEST_CODE, new Intent(context, MainActivity.class),
PendingIntent.FLAG_UPDATE_CURRENT);
NotificationManager manager =
(NotificationManager) context.getSystemService(NOTIFICATION_SERVICE);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
manager.createNotificationChannel(createNotificationChannel(context));
}
NotificationCompat.Builder builder = new NotificationCompat.Builder(context, CHANNEL_ID)
.setContentTitle(section)
.setContentText(title)
.setContentIntent(contentPendingIntent)
.setSmallIcon(R.drawable.app_icon)
.setPriority(NotificationCompat.PRIORITY_HIGH)
.setDefaults(NotificationCompat.DEFAULT_ALL)
.setAutoCancel(true);
manager.notify(0, builder.build());
}
When Onchanged in JobService works I get the list and show a notification. Notification opens MainActivity which makes new call to api as it always did. What changes do I have to make in order the MainActivity to show the list that I got from the service??? I really can't tie this up together.
I heard of IPC but wouldn't do that, I want some simpler practice which I sure exists which I just don't know about.
Also, there are two cases: Notification came and MainActivity is open, app is open but MainActivity is not in the foreground and app is on the background or closed. How should I handle each of these cases?
See also piece of code from MainActivity onCreate:
mArticleViewModel = ViewModelProviders.of(this).get(ArticleViewModel.class);
mArticleViewModel.getArticleList(PAGE_NUMBER).observe(this, articles -> {
Log.d(TAG, "List<Result> onChanged!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!");
mProgressBar.setVisibility(View.GONE);
mProgressBarMain.setVisibility(View.GONE);
mIsLoading = false;
mArticles = articles;
Please provide the best practices for this task, I know it's very common I just do it first time and using LiveData makes it way more complicated.
Here is Also Repository code:
public static ArticleRepository getInstance(Application application){
if(INSTANCE == null){
return new ArticleRepository(application);
}
return INSTANCE;
}
private ArticleRepository(Application application) {
Log.d(TAG, "ArticleRepository constructor");
mContext = application;
mArticles = new MutableLiveData<>();
ArticleRoomDatabase db = ArticleRoomDatabase.getInstance(application);
mArticleDao = db.articleDao();
}
public LiveData<List<Article>> getArticles(int page) {
Log.d(TAG, "getArticles");
if (NetworkUtils.isOnline(mContext)) {
Log.d(TAG, "isOnline");
mArticles = loadFromNetwork(page);
} else {
Log.d(TAG, "is NOT Online");
mArticles = loadFromDB(page);
}
}

You have this problem specifically because your Repository implementation is incorrect.
public LiveData<List<Article>> getArticles(int page) {
Log.d(TAG, "getArticles");
if (NetworkUtils.isOnline(mContext)) {
Log.d(TAG, "isOnline");
mArticles = loadFromNetwork(page);
} else {
Log.d(TAG, "is NOT Online");
mArticles = loadFromDB(page);
}
}
If you check the code for NetworkBoundResource, the trick is that you have a single LiveData that binds together the ability to both load from network, and to load from database.
In your case, you are replacing the database's auto-updating query results whenever you have network access - which is why you can't update the MainActivity.
The easiest way (without using a MediatorLiveData) is to have two separate functions on Repository: one for fetchFromNetwork, and one for fetchFromDatabase. The MainActivity should always fetch from database, while the Service always triggers load from network (and inserts it directly into database via a Dao).
This way, the observe function in MainActivity will receive the latest data when Service inserts the data into DB on background thread.

Strange LiveData behaviour?

Im trying to implement MVVM architecture using ViewModel and LiveData. These two methods are inside a Activity:
private void handleResult(BoardViewModel vm) {
vm.getLiveDataSingleObj("Result").observe(this, new Observer<Object>() {
#Override
public void onChanged(#Nullable Object resultObj) {
Result result = (Result) resultObj;
if (!result.isCompleted()) return;
gotoResult();
}
});
}
And
private void gotoResult() {
Log.w(LOG_TAG, "Result: Moving to next activity");
Intent intent = new Intent(boardActivity, ResultActivity.class);
intent.putExtra("LEVEL", levelIndex);
intent.putExtra("MAP", mapIndex);
startActivity(intent);
}
The handleResult method is setup to listen for result objects that indicate that the game has ended and it is time to move on to the next activity ("gotoResult"). However, this completely breaks the navigation of the app, when i go back and then say attempt to start a new game session i instead instantly go to the next activity telling me I've already won.
Any ideas as to why it fires multiple times and eventually stops, letting me start a new session. To clarify, if I remove the gotoResult the logic works every single time no errors with indexes out of bounds or what have you, it's only when I add the goto that everything breaks.
ViewModel:
private void setupHashTypes() {
hashLiveData.put(KEY_BOARD, liveDataBoardQuery);
hashLiveData.put(KEY_STEPS_COUNTER, game.getStepsTakenLiveData());
hashLiveData.put(KEY_PATH_CHANGE, game.getPathChangedLiveData());
hashLiveData.put(KEY_VALUE_CHANGE, game.getValueChangeLiveData());
hashLiveData.put(KEY_TIMER, game.getTimerLiveData());
hashLiveData.put(KEY_SELECTED, game.getSelectedLiveData());
hashLiveData.put(KEY_DESELECTED, game.getDeselectedLiveData());
hashLiveData.put(KEY_HOLD, game.getHoldLiveData());
hashLiveData.put(KEY_UNHOLD, game.getUnholdLiveData());
hashLiveData.put(KEY_RESULT, game.getResultLiveData());
}
public LiveData<Object> getLiveDataSingleObj(String type) {
if (hashLiveData.containsKey(type)) {
return (LiveData<Object>) hashLiveData.get(type);
}
throw new IllegalArgumentException("Invalid: key was not found: " + type);
}
And the Model has getters, example:
private final SingleLiveEvent<Result> resultLiveData = new SingleLiveEvent<>();
public LiveData<Result> getResultLiveData() {
return resultLiveData;
}

you should remove the observer in onDestroy() method

Changing from MutableLiveData which always resends the previous set values to new subscribers, to SingleLiveEvent which doesn't have this behaviour, solved the problem.
The class can be found here: https://github.com/googlesamples/android-architecture/tree/dev-todo-mvvm-live/todoapp/app/src/main/java/com/example/android/architecture/blueprints/todoapp

Android Beacon Library, Null Object Reference when calling startRangingBeaconsInRegion

I'm developing an android app using beacon library, part of this app is about to search for a specific beacon via its minor ID (which is inserted by user via dialog).
if I write everything in the same activity things works fine but I'd like to keep dialogs separate in an external pure java class, so in the activity implementing BeaconConsumer I added a "method" creating and binding the beacon manager.
public class Activity03 extends AppCompatActivity
implements BeaconConsumer, RangeNotifier {
...
public void scanForBeacon(Context context, String selectedMinorId){
beaconManager = BeaconManager.getInstanceForApplication(context);
beaconManager.getBeaconParsers().add(new BeaconParser()
.setBeaconLayout("m:2-3=0215,i:4-19,i:20-21,i:22-23,p:24-24"));
Identifier minorIdFilter = Identifier.parse(selectedMinorId);
myRegion = new Region(
"my_region",
null,
null,
minorIdFilter);
beaconManager.bind((BeaconConsumer) context);
}
...
}
The point is that when calling startRangingBeaconsInRegion, i got:
Attempt to invoke virtual method 'void org.altbeacon.beacon.BeaconManager.startRangingBeaconsInRegion(org.altbeacon.beacon.Region)' on a null object reference
The sequence is:
1. the user is asked (via GoogleApiClient) to switch on BLE and localization
2. inside onActivityResult the dialog for inserting minor ID is picked from the java class DialogUtilities
DialogUtilities.showSelectionDialog(Activity03.this);
3. pressing the button dialog is dismissed, an instance of the BeaconConsumer activity is created and the method called:
Activity03 a03 = new Activity03();
a03.scanForBeacon(context, minorId);
4. when the onBeaconServiceConnect() is called I got null object reference on the line of startRangingBeaconsInRegion
#Override
public void onBeaconServiceConnect() {
try {
beaconManager.startRangingBeaconsInRegion(myRegion);
} catch (RemoteException e) {
e.printStackTrace();
}
}
I'm new of java and android but it doesn't seems to me that problem is about the Region because I've the same response even if I set to null all the Identifiers so I cannot understand why null reference.
Is it possible that I create two different BeaconMangers because of the activity's istance I return by Dialog ? If so how I can solve it?
If not, how to avoid this null object reference?
Thanks in advance
EDIT
BeaconManager declaration
public class Activity03 extends AppCompatActivity implements BeaconConsumer, RangeNotifier {
static final int REQUEST_CHECK_SETTINGS = 1000;
private BeaconManager beaconManager;
private Region myRegion;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setTheme(R.style.AppTheme);
setContentView(R.layout.activity_03);
}
#Override
protected void onResume() {
#Override
super.onResume();
PermissionsUtilities.switchLocationAndBluetooth(Activity03.this);
}
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
final LocationSettingsStates states = LocationSettingsStates.fromIntent(data);
switch (requestCode) {
case REQUEST_CHECK_SETTINGS:
switch (resultCode) {
case Activity.RESULT_OK:
DialogUtilities.showSensorSelectionDialog(Activity03.this);
break;
case Activity.RESULT_CANCELED:
...
break;
default:
break;
}
break;
}
}

You can try the code below to avoid null pointer exception:
beaconManager.setRangeNotifier(new RangeNotifier() {
#Override
public void didRangeBeaconsInRegion(Collection beacons, Region region) {
if (beacons.size() > 0) {
Log.i(TAG, "The first beacon I see is about "+beacons.iterator().next().getDistance()+" meters away.");
}
}
});
try {
beaconManager.startRangingBeaconsInRegion(new Region("myRangingUniqueId", null, null, null));
} catch (RemoteException e) {
e.printStackTrace();
}

The question does not show the declaration of beaconManager and how it is scoped, so it is hard to say the exact cause.
Two tips:
The BeaconManager is a singleton, meaning there is one instance per Java process. So you can always get this instance from within an Activity like this: BeaconManager.getInstanceForApplication(this).startRangingBeaconsInRegion(myRegion);
Manually constructing a new Activity instance as shown below generally will not work in Android programming. You must create new Activity instance using an Intent. In your case I suspect you may not want to create a new Activity instance at all but to get a reference to the existing one. This may be unrelated to what you are asking, but it will certainly need to be changed: Activity03 a03 = new Activity03();
a03.scanForBeacon(context, minorId);