> ## Documentation Index
> Fetch the complete documentation index at: https://docs.baato.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Drop a pin

> Let users drop a pin on the map and reverse geocode it to an address.

This example demonstrates how you can use the [baato-java-client](/libraries/java) library to allow users drop a pin into any location within a given MapView and generate an address corresponding to the location.

<Frame caption="A dropped pin resolved to an address">
  <img src="https://mintcdn.com/baato/3GUKEGLT42m2snov/images/examples/baato_reverse.png?fit=max&auto=format&n=3GUKEGLT42m2snov&q=85&s=bf4f96925133d7362beaa10d20487042" alt="A pin dropped on an Android map, resolved to an address" width="585" height="312" data-path="images/examples/baato_reverse.png" />
</Frame>

<Note>
  Before you begin, please make sure you have the [Baato Java Library](/libraries/java) installed in your app.
</Note>

<Steps>
  <Step title="Add the dependency">
    Specify the required dependency configuration in your app's build.gradle file.

    ```groovy theme={null}
    //mapbox sdk
      implementation('com.mapbox.mapboxsdk:mapbox-android-sdk:6.5.0') {
          exclude group: 'group_name', module: 'module_name'
      }
      implementation 'com.mapbox.mapboxsdk:mapbox-android-plugin-locationlayer:0.8.1'
    ```

    <Warning>
      If you are using MapBox as your map service, the Baato client currently supports only the versions pinned above.
    </Warning>
  </Step>

  <Step title="Add a MapView to your layout">
    ```xml theme={null}
        <com.mapbox.mapboxsdk.maps.MapView
            android:id="@+id/mapView"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            mapbox:mapbox_cameraTargetLat="27.7084"
            mapbox:mapbox_cameraTargetLng="85.3206"
            mapbox:mapbox_cameraZoom="13"
            android:visibility="visible"
            />
    ```
  </Step>

  <Step title="Instantiate the MapView with a Baato style">
    ```java theme={null}
    public class LocationPickerActivity extends AppCompatActivity {
        private MapView mapView;
        private MapboxMap mapboxMap;
        private TextView bottomInfoLayout;
        private Icon selectedMarkerIcon;
        private MarkerOptions marker;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_location_picker);
            mapView = findViewById(R.id.mapView);
            bottomInfoLayout = findViewById(R.id.bottomInfoLayout);

            Mapbox.getInstance(this, getString(R.string.mapbox_token));
            mapView.onCreate(savedInstanceState);
            mapView.getMapAsync(mapboxMap ->
            {
                //remove mapbox attribute
                mapboxMap.getUiSettings().setAttributionEnabled(false);
                mapboxMap.getUiSettings().setLogoEnabled(false);
                //add your map style url here
                mapboxMap.setStyleUrl("https://api.baato.io/api/v1/styles/retro?key=" + getString(R.string.baato_access_token),
                        style -> {
                            this.mapboxMap = mapboxMap;
                            mapView.setVisibility(View.VISIBLE);
                            initClickedMarker(mapboxMap); //to initialize a marker icon for selected location
                        });
            });
        }
    ```
  </Step>

  <Step title="Handle map taps with a MapClickListener">
    ```java theme={null}
        private void initClickedMarker(MapboxMap mapboxMap) {
            Drawable drawabled = ResourcesCompat.getDrawable(getResources(), R.drawable.mapbox_marker_icon_default, null);
            Bitmap dBitmap = BitmapUtils.getBitmapFromDrawable(drawabled);
            assert dBitmap != null;
            IconFactory mIconFactory = IconFactory.getInstance(this);
            selectedMarkerIcon = mIconFactory.fromBitmap(dBitmap);

            // Handle tap events on the map
            mapboxMap.addOnMapClickListener(point ->
                    updateMarkerPosition(point));
        }

        // Change the position of the marker
        private void updateMarkerPosition(LatLng point) {
            if (marker == null) {
                marker = new MarkerOptions().icon(selectedMarkerIcon).position(point);
                mapboxMap.addMarker(marker);
            } else if (!mapboxMap.getMarkers().isEmpty()) {
                Marker marker = mapboxMap.getMarkers().get(0);
                marker.setPosition(point);
                mapboxMap.updateMarker(marker);
            }
            moveCameraTo(point);

            getAddressFromLibrary(point); // To make a reverse geocoding search using the tapped coordinates
        }

        private void moveCameraTo(LatLng point) {
            double zoom = mapboxMap.getCameraPosition().zoom;
            if (zoom < 10)
                zoom = 13;
            else if (zoom < 13)
                zoom = 15;
            else if (zoom < 15)
                zoom = zoom + 1;
            else if (zoom < 18)
                zoom = zoom + 1;
            mapboxMap.animateCamera(CameraUpdateFactory.newLatLngZoom(point, zoom), 300);
        }
    ```
  </Step>

  <Step title="Reverse geocode the marker position">
    Follow [java-library](/libraries/java) to add the required dependency and perform reverse search using baato reverse search library wherever the user taps on the map.

    ```java theme={null}
        private void getAddressFromLibrary(LatLng point) {
            new BaatoReverse(this)
                    .setLatLon(new LatLon(point.getLatitude(), point.getLongitude()))
                    .setAccessToken(getString(R.string.baato_access_token))
                    .setRadius(2)
                    .withListener(new BaatoReverse.BaatoReverseRequestListener() {
                        @Override
                        public void onSuccess(PlaceAPIResponse places) {

                            // If the geocoder returns a result, we take the first in the list and show the address with the place name.
                            if (!places.getData().isEmpty()) {
                                Place place = places.getData().get(0);
                                bottomInfoLayout.setText(Html.fromHtml("<b><h6>" + place.getName() + "</h6></b>" + place.getAddress()));
                            } else {
                                bottomInfoLayout.setText("No address found!");
                            }
                        }

                        @Override
                        public void onFailed(Throwable error) {
                            bottomInfoLayout.setText(error.getMessage());
                        }
                    })
                    .doRequest();
        }
    ```
  </Step>
</Steps>

<Card title="View the full example on GitHub" icon="github" href="https://github.com/baato/baato-android-demo/blob/master/app/src/main/java/com/baato/baatoandroiddemo/activities/LocationPickerActivity.java" horizontal />