# Intercept map click and long click events using NavNextbillionMap This example shows how to intercept the NavNextbillionMap click and long click events and add corresponding actions to them. Currently, a toast message is added to each click and long click event, which shows the tapped location latitude and longitude. ![documentation image]() For all code examples, refer to [Navigation Code Examples](https://github.com/nextbillion-ai/nb-navigation-android-demo) **activity_intercept_click_events.xml [view source](https://github.com/nextbillion-ai/nb-navigation-android-demo/blob/main/app/src/main/res/layout/activity_intercept_click_events.xml)** ```xml ``` **InterceptMapClickActivity [view source](https://github.com/nextbillion-ai/nb-navigation-android-demo/blob/main/app/src/main/java/ai/nextbillion/navigation/demo/activity/InterceptMapClickActivity.java)** ```java package ai.nextbillion.navigation.demo.activity; import android.os.Bundle; import android.widget.Toast; import androidx.annotation.NonNull; import androidx.annotation.Nullable; import androidx.appcompat.app.AppCompatActivity; import ai.nextbillion.kits.geojson.Point; import ai.nextbillion.maps.camera.CameraUpdate; import ai.nextbillion.maps.camera.CameraUpdateFactory; import ai.nextbillion.maps.core.MapView; import ai.nextbillion.maps.core.NextbillionMap; import ai.nextbillion.maps.core.OnMapReadyCallback; import ai.nextbillion.maps.core.Style; import ai.nextbillion.maps.geometry.LatLng; import ai.nextbillion.maps.location.modes.RenderMode; import ai.nextbillion.navigation.demo.R; import ai.nextbillion.navigation.ui.camera.CameraUpdateMode; import ai.nextbillion.navigation.ui.camera.NavigationCameraUpdate; import ai.nextbillion.navigation.ui.map.NavNextbillionMap; /*** * This class shows how to intercept the click and long click events of nbMap */ public class InterceptMapClickActivity extends AppCompatActivity implements OnMapReadyCallback, NextbillionMap.OnMapClickListener, NextbillionMap.OnMapLongClickListener { private static final int CAMERA_ANIMATION_DURATION = 1000; private static final int DEFAULT_CAMERA_ZOOM = 16; private MapView mapView; private NavNextbillionMap nbMap; // a fake point in Singapore private final Point fakePoint = Point.fromLngLat(103.852408, 1.276411); @Override protected void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_intercept_click_events); mapView = findViewById(R.id.mapView_intercept_click_events); mapView.onCreate(savedInstanceState); mapView.getMapAsync(this); } @Override public boolean onMapClick(@NonNull LatLng latLng) { Toast.makeText( InterceptMapClickActivity.this, String.format("Map was clicked with lat:%s, long: %s", latLng.getLatitude(), latLng.getLongitude()), Toast.LENGTH_LONG).show(); return false; } @Override public boolean onMapLongClick(@NonNull LatLng latLng) { Toast.makeText( InterceptMapClickActivity.this, String.format("Map was long clicked with lat:%s, long: %s", latLng.getLatitude(), latLng.getLongitude()), Toast.LENGTH_LONG).show(); return false; } @Override public void onMapReady(@NonNull NextbillionMap nextbillionMap) { nextbillionMap.setStyle(new Style.Builder().fromUri("https://api.nextbillion.io/maps/streets/style.json")); nextbillionMap.getStyle(style -> { // add the following listeners to nextbillionMap so the override onClick methods could work nextbillionMap.addOnMapClickListener(InterceptMapClickActivity.this); nextbillionMap.addOnMapLongClickListener(InterceptMapClickActivity.this); nbMap = new NavNextbillionMap(mapView, nextbillionMap); nbMap.updateLocationLayerRenderMode(RenderMode.COMPASS); animateCamera(); }); } private void animateCamera() { CameraUpdate cameraUpdate = CameraUpdateFactory.newLatLngZoom(new LatLng(fakePoint.latitude(), fakePoint.longitude()), DEFAULT_CAMERA_ZOOM); NavigationCameraUpdate navigationCameraUpdate = new NavigationCameraUpdate(cameraUpdate); navigationCameraUpdate.setMode(CameraUpdateMode.OVERRIDE); nbMap.retrieveCamera().update(navigationCameraUpdate, CAMERA_ANIMATION_DURATION); } @Override public void onStart() { super.onStart(); mapView.onStart(); } @Override public void onResume() { super.onResume(); mapView.onResume(); } @Override public void onLowMemory() { super.onLowMemory(); mapView.onLowMemory(); } @Override public void onPause() { super.onPause(); mapView.onPause(); } @Override public void onStop() { super.onStop(); mapView.onStop(); } @Override protected void onDestroy() { super.onDestroy(); mapView.onDestroy(); } } ``` ### Code Highlights The **InterceptMapClickActivity** class can be used to intercept clicks and long clicks on a map. It can be used to display a Toast message with the latitude and longitude of the clicked point. The single tap event is intercepted in **onMapClick()** method, and the long click event is intercepted in **onMapLongClick()** method. ### Code summary The InterceptMapClickActivity class extends AppCompatActivity and implements the OnMapReadyCallback, NextbillionMap.OnMapClickListener, and NextbillionMap.OnMapLongClickListener interfaces. It uses the NextbillionMap library to display a map and listen for clicks and long clicks on the map. The class has the following members: - **CAMERA_ANIMATION_DURATION**: The duration of the camera animation when the map is initialized. - **DEFAULT_CAMERA_ZOOM**: The default zoom level of the map. - **mapView**: A MapView object that displays the map. - **nbMap**: A NavNextbillionMap object that provides access to the NextbillionMap library. - **fakePoint**: A Point object that represents a fake point in Singapore. The class implements the following methods: - **onCreate()**: This method is called when the activity is created. It initializes the mapView object and sets the CAMERA_ANIMATION_DURATION and DEFAULT_CAMERA_ZOOM constants. It also gets the map style from the NextbillionMap library and adds the OnMapClickListener and OnMapLongClickListener interfaces to the map. - **onMapClick()**: This method is called when the map is clicked. It displays a Toast message with the latitude and longitude of the clicked point. - **onMapLongClick()**: This method is called when the map is long-clicked. It displays a Toast message with the latitude and longitude of the clicked point. - **onMapReady()**: This method is called when the map is ready. It sets the style of the map and animates the camera to the fakePoint location. - **animateCamera()**: This method animates the camera to the fakePoint location. - **onStart()**: This method is called when the activity starts. It calls the onStart() method of the mapView object. - **onResume()**: This method is called when the activity resumes. It calls the onResume() method of the mapView object. - **onLowMemory()**: This method is called when the device is low on memory. It calls the onLowMemory() method of the mapView object. - **onPause()**: This method is called when the activity pauses. It calls the onPause() method of the mapView object. - **onStop()**: This method is called when the activity stops. It calls the onStop() method of the mapView object. - **onDestroy()**: This method is called when the activity is destroyed. It calls the onDestroy() method of the mapView object.