I am using Here maps SDK and have initialized the map and PositioningManager for get the current location of user in initialize() method now I have 2 getDirections(View v) which is being called from the view layout xml file hence it is able to access the posManager which is instance of PositioningManager class but my second method track_my_ride which gets called by Button.onclick method and here when I try to use posManager app throws an error
com.sjain.routeplanner E/AndroidRuntime: FATAL EXCEPTION: main Process: com.sjain.routeplanner, PID: 26948 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.sjain.routeplanner/com.sjain.routeplanner.ViewMapActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'com.here.android.mpa.common.GeoPosition com.here.android.mpa.common.PositioningManager.getPosition()' on a null object reference
......
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'com.here.android.mpa.common.GeoPosition com.here.android.mpa.common.PositioningManager.getPosition()' on a null object referenceat com.sjain.routeplanner.ViewMapActivity.track_my_ride(ViewMapActivity.java:334) at com.sjain.routeplanner.ViewMapActivity.intentInfo(ViewMapActivity.java:137) at com.sjain.routeplanner.ViewMapActivity.onCreate(ViewMapActivity.java:101) at android.app.Activity.performCreate(Activity.java:6298)
.....
I have read answers how to pass the current activity view also but none of them seems to work. This exception does not occur if I try to access posManager from my getDirection(View v) method which has the view reference so I suppose it's not the issue of my posManager not being initialized.
This is my ViewMapActivity.java file
public class ViewMapActivity extends AppCompatActivity {
private static final String LOG_TAG = ViewMapActivity.class.getSimpleName();
// permissions request code
private final static int REQUEST_CODE_ASK_PERMISSIONS = 1;
/**
* Permissions that need to be explicitly requested from end user.
*/
private static final String[] REQUIRED_SDK_PERMISSIONS = new String[]{
Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.WRITE_EXTERNAL_STORAGE,
Manifest.permission.READ_EXTERNAL_STORAGE, Manifest.permission.ACCESS_COARSE_LOCATION};
// map embedded in the map fragment
private Map map = null;
// map fragment embedded in this activity
private MapFragment mapFragment = null;
// TextView for displaying the current map scheme
private TextView textViewResult;
// MapRoute for this activity
private static MapRoute mapRoute = null;
private PositioningManager posManager;
boolean paused = false;
private MapMarker marker;
private RouteItem route = null;
// Define positioning listener
PositioningManager.OnPositionChangedListener positionListener = new
PositioningManager.OnPositionChangedListener() {
public void onPositionUpdated(PositioningManager.LocationMethod method,
GeoPosition position, boolean isMapMatched) {
// set the center only when the app is in the foreground
// to reduce CPU consumption
if (!paused) {
map.setCenter(position.getCoordinate(),
Map.Animation.NONE);
Log.d("MainActivity.class", "onPositionUpdated: " + position.getCoordinate().toString());
marker.setCoordinate(position.getCoordinate());
}
}
@Override
public void onPositionFixChanged(PositioningManager.LocationMethod locationMethod, PositioningManager.LocationStatus locationStatus) {
Log.d("MainActivity.class", "onPositionFixChanged: " + locationStatus);
String status = locationStatus.toString();
if (Objects.equals(status, "AVAILABLE")) {
marker.setCoordinate(posManager.getPosition().getCoordinate());
} else if (Objects.equals(status, "TEMPORARILY_UNAVAILABLE")) {
marker.setCoordinate(posManager.getLastKnownPosition().getCoordinate());
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
checkPermissions();
intentInfo();
}
private void intentInfo() {
try{
......
String type = this.getIntent().getStringExtra("type");
// if type is display just display the route
// if track then display the eta and current status
if(Objects.equals(type, "track")) {
String location = this.getIntent().getStringExtra("location");
track_my_ride(location);
}
}
catch (Error e) {
Log.e("ViewMapActivity.class", "intentInfo: ", e);
}
}
@Override
protected void onResume() {
super.onResume();
paused = false;
if (posManager != null) {
posManager.start(PositioningManager.LocationMethod.GPS);
}
}
@Override
protected void onPause() {
super.onPause();
if (posManager != null) {
posManager.stop();
}
paused = true;
super.onPause();
}
@Override
protected void onDestroy() {
if (posManager != null) {
// Cleanup
posManager.removeListener(positionListener);
}
map = null;
super.onDestroy();
}
private void initialize() {
setContentView(R.layout.activity_map_view);
// Search for the map fragment to finish setup by calling init().
mapFragment = (MapFragment) getFragmentManager().findFragmentById(R.id.mapFragment);
mapFragment.init(new OnEngineInitListener() {
@Override
public void onEngineInitializationCompleted(OnEngineInitListener.Error error) {
if (error == OnEngineInitListener.Error.NONE) {
// retrieve a reference of the map from the map fragment
map = mapFragment.getMap();
// Set the map center coordinate to the Vancouver region (no animation)
map.setCenter(new GeoCoordinate(19.152568, 72.855825), Map.Animation.NONE);
// Set the map zoom level to the average between min and max (no animation)
map.setZoomLevel((map.getMaxZoomLevel() + map.getMinZoomLevel()) / 2);
// get users current location
posManager = PositioningManager.getInstance();
posManager.start(PositioningManager.LocationMethod.GPS);
posManager.addListener(new WeakReference<>(positionListener));
// create marker to display users current location
marker = new MapMarker();
marker.setCoordinate(posManager.getLastKnownPosition().getCoordinate());
map.addMapObject(marker);
} else {
Log.e(LOG_TAG, "Cannot initialize MapFragment (" + error + ")");
}
}
});
}
/**
* Checks the dynamically controlled permissions and requests missing permissions from end user.
*/
protected void checkPermissions() {
final List<String> missingPermissions = new ArrayList<>();
// check all required dynamic permissions
for (final String permission : REQUIRED_SDK_PERMISSIONS) {
final int result = ContextCompat.checkSelfPermission(this, permission);
if (result != PackageManager.PERMISSION_GRANTED) {
missingPermissions.add(permission);
}
}
if (!missingPermissions.isEmpty()) {
// request all missing permissions
final String[] permissions = missingPermissions
.toArray(new String[missingPermissions.size()]);
ActivityCompat.requestPermissions(this, permissions, REQUEST_CODE_ASK_PERMISSIONS);
} else {
final int[] grantResults = new int[REQUIRED_SDK_PERMISSIONS.length];
Arrays.fill(grantResults, PackageManager.PERMISSION_GRANTED);
onRequestPermissionsResult(REQUEST_CODE_ASK_PERMISSIONS, REQUIRED_SDK_PERMISSIONS,
grantResults);
}
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String permissions[],
@NonNull int[] grantResults) {
switch (requestCode) {
case REQUEST_CODE_ASK_PERMISSIONS:
for (int index = permissions.length - 1; index >= 0; --index) {
if (grantResults[index] != PackageManager.PERMISSION_GRANTED) {
// exit the app if one permission is not granted
Toast.makeText(this, "Required permission '" + permissions[index]
+ "' not granted, exiting", Toast.LENGTH_LONG).show();
finish();
return;
}
}
// all permissions were granted
initialize();
break;
}
}
public void getDirections(View v) {
// posManager Works here without any error.
GeoCoordinate coordinate;
if(posManager.getPosition().getCoordinate() != null) {
coordinate = posManager.getPosition().getCoordinate();
}
else if(posManager.getLastKnownPosition().getCoordinate() != null ){
coordinate = posManager.getLastKnownPosition().getCoordinate();
}
else {
// default nesco it park coordinates
//coordinates taken from here maps
coordinate = new GeoCoordinate(19.15254,72.85571);
}
}
public void track_my_ride(String location) {
// 1. clear previous results
textViewResult = (TextView) findViewById(R.id.result);
textViewResult.setText("");
if (map != null && mapRoute != null) {
map.removeMapObject(mapRoute);
mapRoute = null;
}
// 2. Initialize RouteManager
RouteManager routeManager = new RouteManager();
// 3. Select routing options
RoutePlan routePlan = new RoutePlan();
RouteOptions routeOptions = new RouteOptions();
routeOptions.setTransportMode(RouteOptions.TransportMode.CAR);
routeOptions.setRouteType(RouteOptions.Type.FASTEST);
routePlan.setRouteOptions(routeOptions);
GeoCoordinate coordinate;
if(posManager.getPosition().getCoordinate() != null) {
coordinate = posManager.getPosition().getCoordinate();
}
else if(posManager.getLastKnownPosition().getCoordinate() != null ){
coordinate = posManager.getLastKnownPosition().getCoordinate();
}
else {
// default nesco it park coordinates
//coordinates taken from here maps
coordinate = new GeoCoordinate(19.15254,72.85571);
}
// 4. Select Waypoints for your routes
routePlan.addWaypoint(coordinate);
// supposed to be current or last known location of bus
String[] bus_coordinate = location.split(",");
routePlan.addWaypoint(new GeoCoordinate(
Double.parseDouble(bus_coordinate[0]),
Double.parseDouble(bus_coordinate[1])));
// 5. Retrieve Routing information via RouteManagerEventListener
RouteManager.Error error = routeManager.calculateRoute(routePlan, routeManagerListener);
if (error != RouteManager.Error.NONE) {
Toast.makeText(getApplicationContext(),
"Route calculation failed with: " + error.toString(), Toast.LENGTH_SHORT)
.show();
}
}
private RouteManager.Listener routeManagerListener = new RouteManager.Listener() {
public void onCalculateRouteFinished(RouteManager.Error errorCode,
List<RouteResult> result) {
if (errorCode == RouteManager.Error.NONE && result.get(0).getRoute() != null) {
// create a map route object and place it on the map
mapRoute = new MapRoute(result.get(0).getRoute());
map.addMapObject(mapRoute);
// Get the bounding box containing the route and zoom in (no animation)
GeoBoundingBox gbb = result.get(0).getRoute().getBoundingBox();
map.zoomTo(gbb, Map.Animation.NONE, Map.MOVE_PRESERVE_ORIENTATION);
textViewResult.setText(String.format(getString(R.string.route_maneuvers), result.get(0).getRoute().getManeuvers().size()));
} else {
textViewResult.setText(
String.format("Route calculation failed: %s", errorCode.toString()));
}
}
public void onProgress(int percentage) {
textViewResult.setText(String.format(getString(R.string.precent_done), percentage));
}
};
}
Can someone please help me out here
EDIT
After seeing the error it might seem like I have not initialized posManager but I have already initialized it while initializing my MAP without any error.
How am I supposed to get the instance of posManager in track_my_ride() method even though it should be accessible to complete class and I can access it in other method having reference to View i.e. getDirection(View v) but not in track_my_ride() method
