Getting the next turn/direction in Mapbox - maps

Question

I'm trying to get the direction of the upcoming turn while travelling, i.e. I want to trigger an event in my app according to the direction of the upcoming turn.
I've tried using event listeners, taking help of the documentation and the provided examples but as I'm pretty new to android studio and mapbox, I've not been successful (my app either crashed or the function would never get triggered). I've also tried searching for getting the voice commands into text form or log form but have failed.
While my current code does display directions and gives voiced instructions, I can't figure out how to access either of them. I'd like to know if there's a simple way of achieving what I'm after without using any event listeners.
private MapView mapView;
private MapboxMap mapboxMap;
private PermissionsManager permissionsManager;
private LocationComponent locationComponent;
private DirectionsRoute currentRoute;
private static final String TAG = "DirectionsActivity";
private NavigationMapRoute navigationMapRoute;
private MapboxNavigation navigation;
private Button button;
private NavigationView navigationView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Mapbox.getInstance(this, getString(R.string.access_token));
setContentView(R.layout.activity_main);
mapView = findViewById(R.id.mapView);
mapView.onCreate(savedInstanceState);
mapView.getMapAsync(this);
// Toast.makeText(this, "Hello", Toast.LENGTH_SHORT).show();
}
#Override
public void onMapReady(#NonNull final MapboxMap mapboxMap) {
this.mapboxMap = mapboxMap;
//Toast.makeText(this, "Hello", Toast.LENGTH_SHORT).show();
mapboxMap.setStyle(getString(R.string.navigation_guidance_day), new Style.OnStyleLoaded() {
#Override
public void onStyleLoaded(#NonNull Style style) {
enableLocationComponent(style);
addDestinationIconSymbolLayer(style);
mapboxMap.addOnMapClickListener(MainActivity.this);
button = findViewById(R.id.startButton);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
boolean simulateRoute = true;
NavigationLauncherOptions options = NavigationLauncherOptions.builder()
.directionsRoute(currentRoute)
.shouldSimulateRoute(simulateRoute)
.build();
NavigationLauncher.startNavigation(MainActivity.this, options);
}
});
}
});
}
private void addDestinationIconSymbolLayer(#NonNull Style loadedMapStyle) {
loadedMapStyle.addImage("destination-icon-id",
BitmapFactory.decodeResource(this.getResources(), R.drawable.mapbox_marker_icon_default));
GeoJsonSource geoJsonSource = new GeoJsonSource("destination-source-id");
Log.d(TAG, "addDestinationIconSymbolLayer: " + geoJsonSource);
loadedMapStyle.addSource(geoJsonSource);
SymbolLayer destinationSymbolLayer = new SymbolLayer("destination-symbol-layer-id", "destination-source-id");
destinationSymbolLayer.withProperties(
iconImage("destination-icon-id"),
iconAllowOverlap(true),
iconIgnorePlacement(true)
);
loadedMapStyle.addLayer(destinationSymbolLayer);
}
#SuppressWarnings( {"MissingPermission"})
#Override
public boolean onMapClick(#NonNull LatLng point) {
Point destinationPoint = Point.fromLngLat(point.getLongitude(), point.getLatitude());
Point originPoint = Point.fromLngLat(locationComponent.getLastKnownLocation().getLongitude(),
locationComponent.getLastKnownLocation().getLatitude());
GeoJsonSource source = mapboxMap.getStyle().getSourceAs("destination-source-id");
Log.d(TAG, "Does this even work");
Log.d(TAG, "onMapClick: " + source.toString());
if (source != null) {
source.setGeoJson(Feature.fromGeometry(destinationPoint));
}
getRoute(originPoint, destinationPoint);
button.setEnabled(true);
button.setBackgroundResource(R.color.mapboxBlue);
return true;
}
private void getRoute(Point origin, Point destination) {
NavigationRoute.builder(this)
.accessToken(Mapbox.getAccessToken())
.origin(origin)
.destination(destination)
.build()
.getRoute(new Callback<DirectionsResponse>() {
#Override
public void onResponse(Call<DirectionsResponse> call, Response<DirectionsResponse> response) {
Log.d(TAG, "Response code: " + response.code());
if (response.body() == null) {
Log.e(TAG, "No routes found, make sure you set the right user and access token.");
return;
} else if (response.body().routes().size() < 1) {
Log.e(TAG, "No routes found");
return;
}
currentRoute = response.body().routes().get(0);
if (navigationMapRoute != null) {
navigationMapRoute.removeRoute();
} else {
navigationMapRoute = new NavigationMapRoute(null, mapView, mapboxMap, R.style.NavigationMapRoute);
}
navigationMapRoute.addRoute(currentRoute);
}
#Override
public void onFailure(Call<DirectionsResponse> call, Throwable throwable) {
Log.e(TAG, "Error: " + throwable.getMessage());
}
});
}
#SuppressWarnings( {"MissingPermission"})
private void enableLocationComponent(#NonNull Style loadedMapStyle) {
if (PermissionsManager.areLocationPermissionsGranted(this)) {
locationComponent = mapboxMap.getLocationComponent();
locationComponent.activateLocationComponent(this, loadedMapStyle);
locationComponent.setLocationComponentEnabled(true);
locationComponent.setCameraMode(CameraMode.TRACKING);
} else {
permissionsManager = new PermissionsManager(this);
permissionsManager.requestLocationPermissions(this);
}
}
#Override
public void onRequestPermissionsResult(int requestCode, #NonNull String[] permissions, #NonNull int[] grantResults) {
permissionsManager.onRequestPermissionsResult(requestCode, permissions, grantResults);
}
#Override
public void onExplanationNeeded(List<String> permissionsToExplain) {
Toast.makeText(this, R.string.user_location_permission_explanation, Toast.LENGTH_LONG).show();
}
#Override
public void onPermissionResult(boolean granted) {
if (granted) {
enableLocationComponent(mapboxMap.getStyle());
} else {
Toast.makeText(this, R.string.user_location_permission_not_granted, Toast.LENGTH_LONG).show();
finish();
}
}
// Add the mapView's own lifecycle methods to the activity's lifecycle methods
#Override
public void onStart() {
super.onStart();
mapView.onStart();
}
#Override
public void onResume() {
super.onResume();
mapView.onResume();
// Toast.makeText(this, "Hello", Toast.LENGTH_SHORT).show();
}
#Override
public void onPause() {
super.onPause();
mapView.onPause();
}
#Override
public void onStop() {
super.onStop();
mapView.onStop();
}
#Override
public void onLowMemory() {
super.onLowMemory();
mapView.onLowMemory();
}
#Override
protected void onDestroy() {
super.onDestroy();
mapView.onDestroy();
}
#Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
mapView.onSaveInstanceState(outState);
}
}

Answer 1

It sounds like you might want to look at using an event listener for a custom milestone. Here's a link to the docs:
https://docs.mapbox.com/android/navigation/overview/milestones/#milestone-event-listener