Use Google Fused Location Provider with MapsIndoors

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To get started with Google Fused Location Provider, you need to create a positioning implementation which enables communicating the positions received from the API with the MapsIndoors SDK.

The Position Provider implementation exists at the customer application level, and needs to use the PositionProvider interface from the MapsIndoors SDK. The MapsIndoors SDK can then use the positioning results given by the given Position Provider, by setting the Position Provider with MapControl.setPositionProvider(PositionProvider).

Implementing Google Fused Location Provider API

This Guide requires you to already have an activity that shows a MapsIndoors Map and to have the Google Play Services Location library dependency added to your project.

dependencies {
implementation 'com.google.android.gms:play-services-location:18.0.0'
}

We start by implementing a Positioning Provider service. This service is needed so you can have mulitple positioning providers running in the same application, and have the code stored in one location.

To begin, create a class with a constructor that receives an Activity and a MapControl object.

PositionProviderService.java
public class PositionProviderService {
private MapControl mMapControl;
private Activity mActivity;

public PositionProviderService(Activity activity, MapControl mapControl) {
mMapControl = mapControl;
mActivity = activity;
}
}

Now we will start implementing the Fused Location position provider. Create a class called GPSPositionProvider that implements the PositionProvider interface from the MapsIndoors SDK, and create a constructor that takes a Context as parameter.

GPSPositionProvider.java
public class GPSPositionProvider implements PositionProvider {
private Context mContext;

public GPSPositionProvider(@NonNull Context context) {
mContext = context;
}
}

We will start by implementing logic to each of the implemented methods from the PositionProvider interface.

GPSPositionProvider.java
public class GPSPositionProvider implements PositionProvider {

private final String[] REQUIRED_PERMISSIONS = new String[]{
"android.permission.ACCESS_FINE_LOCATION",
"android.permission.ACCESS_COARSE_LOCATION"
};

private boolean mIsRunning;
private boolean mIsEnabled;

private String mProviderId;

private final List<OnStateChangedListener> mOnStateChangedListenersList = new ArrayList<>();
private final List<OnPositionUpdateListener> mOnPositionUpdateListeners = new ArrayList<>();

private PositionResult mLatestPosition;

private FusedLocationProviderClient fusedLocationClient;

@NonNull
@Override
public String[] getRequiredPermissions() {
return REQUIRED_PERMISSIONS;
}

@Override
public boolean isPSEnabled() {
return mIsEnabled;
}

@SuppressLint("MissingPermission")
@Override
public void startPositioning(@Nullable String args) {
//Implemented later in guide.
}

@Override
public void stopPositioning(@Nullable String args) {
//Implemented later in guide.
}

@Override
public boolean isRunning() {
return mIsRunning;
}

@Override
public void addOnPositionUpdateListener(@Nullable OnPositionUpdateListener onPositionUpdateListener) {
if( onPositionUpdateListener != null ) {
onPositionUpdateListeners.remove( onPositionUpdateListener );
onPositionUpdateListeners.add( onPositionUpdateListener );
}
}

@Override
public void removeOnPositionUpdateListener(@Nullable OnPositionUpdateListener onPositionUpdateListener) {
if( onPositionUpdateListener != null ) {
onPositionUpdateListeners.remove( onPositionUpdateListener );
}
}

@Override
public void setProviderId(@Nullable String id) {
mProviderId = id;
}

@Override
public void addOnStateChangedListener(@Nullable OnStateChangedListener onStateChangedListener) {
if( onStateChangedListener != null ) {
onStateChangedListenersList.remove( onStateChangedListener );
onStateChangedListenersList.add( onStateChangedListener );
}
}

@Override
public void removeOnStateChangedListener(@Nullable OnStateChangedListener onStateChangedListener) {
if( onStateChangedListener != null ) {
onStateChangedListenersList.remove( onStateChangedListener );
}
}

@Override
public void checkPermissionsAndPSEnabled(@Nullable PermissionsAndPSListener permissionsAndPSListener) {
//The implementation of PSUtils and this permission check can be foud on the finished sample. Linked at the bottom of the guide.
PSUtils.checkLocationPermissionAndServicesEnabled( getRequiredPermissions(), mContext, permissionsAndPSListener );
}

@Nullable
@Override
public String getProviderId() {
return mProviderId;
}

@Nullable
@Override
public PositionResult getLatestPosition() {
return mLatestPosition;
}

@Override
public void startPositioningAfter(int i, @Nullable String s) {

}

@Override
public void terminate() {

}
}

We will then start implementing the code to get Google Fused Location positioning up and running.

We start by implementing the startPositioning and stopPositioning methods:

GPSPositionProvider.java
public class GPSPositionProvider implements PositionProvider {
private FusedLocationProviderClient fusedLocationClient;
@SuppressLint("MissingPermission")
@Override
public void startPositioning(@Nullable String args) {
mIsRunning = true;
fusedLocationClient = LocationServices.getFusedLocationProviderClient(mContext);
LocationRequest locationRequest = LocationRequest.create();
locationRequest.setInterval(1000);
locationRequest.setFastestInterval(100);
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);

fusedLocationClient.requestLocationUpdates(locationRequest,
locationCallback,
Looper.getMainLooper());
}

@Override
public void stopPositioning(@Nullable String args) {
fusedLocationClient.removeLocationUpdates(locationCallback);
mIsRunning = false;
}
}

Implement the locationCallBack to the provider to receive and handle the location updates.

GPSPositionProvider.java
public class GPSPositionProvider implements PositionProvider {
...
private LocationCallback locationCallback = new LocationCallback() {
@Override
public void onLocationResult(@NonNull LocationResult locationResult) {
super.onLocationResult(locationResult);
onLocationChanged(locationResult.getLastLocation());
}

@Override
public void onLocationAvailability(@NonNull LocationAvailability locationAvailability) {
super.onLocationAvailability(locationAvailability);
}
};
}

Create the onLocationChanged method to handle the Google location and make it into a PositionResult:

GPSPositionProvider.java
public class GPSPositionProvider implements PositionProvider {
...
final void onLocationChanged( @Nullable final Location location ){
if( location == null ) {
mLatestPosition = null;
mIsEnabled = false;
return;
}

if( mIsRunning ) {
mIsEnabled = true;

final android.location.Location recLocation = new Location( location );

final MPPositionResult newLocation = new MPPositionResult( new Point( recLocation ), recLocation.getAccuracy() );

newLocation.setAndroidLocation( recLocation );

// From Google's Santa tracker:
// "Update our current location only if we've moved at least a metre, to avoid
// jitter due to lack of accuracy in FusedLocationApi"
if( mLatestPosition != null ) {

final Point prevPoint = mLatestPosition.getPoint();
final Point newPoint = newLocation.getPoint();

if( (prevPoint != null) && (newPoint != null) )
{
// Check the distance between the prev and new position in 2D (lat/lng)
final double dist = prevPoint.distanceTo( newPoint );
if( dist <= 1.0 ) {

// Get the altitude too. Just imagine the lady/guy is using a lift/elevator/"spiral staircase"...
// Use the prev position "android location object" altitude value to run the check
final android.location.Location prevLocation = mLatestPosition.getAndroidLocation();
if( prevLocation != null ) {
final double altDiff = Math.abs( recLocation.getAltitude() - prevLocation.getAltitude() );
if( altDiff <= 2.0 ) {
return;
}
}
}
}
}

// GPS always gives the ground level
newLocation.setFloor( Floor.DEFAULT_GROUND_FLOOR_INDEX );

mLatestPosition = newLocation;
mLatestPosition.setProvider( this );
mLatestPosition.setAndroidLocation( recLocation );

//setLatestPosition(mLatestPosition);
reportPositionUpdate();
}
}

public void reportPositionUpdate() {
if(mIsRunning){
for(OnPositionUpdateListener listener : onPositionUpdateListeners){
if(listener != null && mLatestPosition != null){
listener.onPositionUpdate(mLatestPosition);
}
}
}
}
}

Now we need to start up our PositionProvider to get positioning onto our map. This we will do through our PositionProviderService. We start with creating a method to setup the Google positionProvider from the PositionProviderService.

PositionProviderService.java
public class PositionProviderService {
public void setupGooglePositioning() {
mGooglePositioningProvider = new GPSPositionProvider(mActivity);
mGooglePositioningProvider.checkPermissionsAndPSEnabled(new PermissionsAndPSListener() {
@Override
public void onPermissionDenied() { }

@Override
public void onPermissionGranted() {
onGooglePositioningPermissionsGiven();
}

@Override
public void onGPSPermissionAndServiceEnabled() { }

@Override
public void onPermissionRequestError() { }
});
}
}

void onGooglePositioningPermissionsGiven() {
MapsIndoors.setPositionProvider(mGooglePositioningProvider);
MapsIndoors.startPositioning();
mMapControl.showUserPosition(true);

mGooglePositioningProvider.addOnPositionUpdateListener(new OnPositionUpdateListener() {
@Override
public void onPositioningStarted(@NonNull @NotNull PositionProvider positionProvider) {

}

@Override
public void onPositionFailed(@NonNull @NotNull PositionProvider positionProvider) {

}

@Override
public void onPositionUpdate(@NonNull @NotNull PositionResult positionResult) {
mActivity.runOnUiThread(() -> {
mMapControl.getPositionIndicator().setIconFromDisplayRule( new LocationDisplayRule.Builder( "BlueDotRule" )
.setVectorDrawableIcon(android.R.drawable.presence_invisible, 23, 23 )
.setTint(Color.BLUE)
.setShowLabel(true)
.setLabel("You")
.setLabel(null)
.build());
});
}
});
}

Lastly, we need to start this up after initializing our MapControl.

MapsActivity.java
mMapControl.init(miError -> {
mPositionProviderService = new PositionProviderService(yourActivity, mMapControl);
mPositionProviderService.setupGooglePositioning();
}

A full example of the CiscoDNA position provider together with PositionProviderService can be found here: PositionProviders