Descubre cómo encontrar la ubicación actual de un dispositivo Android y mostrar detalles del lugar (una empresa o cualquier lugar de interés) en esa ubicación. Sigue este instructivo para compilar una app para Android con el SDK de Maps para Android, el SDK de Places para Android y el proveedor de ubicación combinada en las APIs de ubicación de los Servicios de Google Play.
Cómo obtener el código
En GitHub, clona o descarga el repositorio de muestras de la versión 2 de la API de Google Maps para Android.
Consulta la versión de Java de la actividad:
// Copyright 2020 Google LLC // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. package com.example.currentplacedetailsonmap; import android.content.DialogInterface; import android.content.pm.PackageManager; import android.location.Location; import android.os.Bundle; import android.util.Log; import android.util.TypedValue; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.widget.FrameLayout; import android.widget.TextView; import android.widget.Toast; import androidx.annotation.NonNull; import androidx.appcompat.app.AlertDialog; import androidx.appcompat.app.AppCompatActivity; import androidx.core.app.ActivityCompat; import androidx.core.content.ContextCompat; import androidx.core.graphics.Insets; import androidx.core.view.ViewCompat; import androidx.core.view.WindowInsetsCompat; import com.google.android.gms.location.FusedLocationProviderClient; import com.google.android.gms.location.LocationServices; import com.google.android.gms.maps.CameraUpdateFactory; import com.google.android.gms.maps.GoogleMap; import com.google.android.gms.maps.OnMapReadyCallback; import com.google.android.gms.maps.SupportMapFragment; import com.google.android.gms.maps.model.CameraPosition; import com.google.android.gms.maps.model.LatLng; import com.google.android.gms.maps.model.Marker; import com.google.android.gms.maps.model.MarkerOptions; import com.google.android.gms.tasks.OnCompleteListener; import com.google.android.gms.tasks.Task; import com.google.android.libraries.places.api.Places; import com.google.android.libraries.places.api.model.CircularBounds; import com.google.android.libraries.places.api.model.Place; import com.google.android.libraries.places.api.net.PlacesClient; import com.google.android.libraries.places.api.net.SearchNearbyRequest; import com.google.android.libraries.places.api.net.SearchNearbyResponse; import java.util.ArrayList; import java.util.Arrays; import java.util.List; /** An activity that displays a map showing the place at the device's current location. */ public class MapsActivityCurrentPlace extends AppCompatActivity implements OnMapReadyCallback { private static final String TAG = MapsActivityCurrentPlace.class.getSimpleName(); private GoogleMap map; private CameraPosition cameraPosition; // The entry point to the Places API. private PlacesClient placesClient; // The entry point to the Fused Location Provider. private FusedLocationProviderClient fusedLocationProviderClient; // A default location (Sydney, Australia) and default zoom to use when location permission is // not granted. private final LatLng defaultLocation = new LatLng(-33.8523341, 151.2106085); private static final int DEFAULT_ZOOM = 15; private static final int PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION = 1; private boolean locationPermissionGranted; // The geographical location where the device is currently located. That is, the last-known // location retrieved by the Fused Location Provider or set via long press. Location lastKnownLocation; // Keys for storing activity state. private static final String KEY_CAMERA_POSITION = "camera_position"; private static final String KEY_LOCATION = "location"; // Used for selecting the current place. private static final int M_MAX_ENTRIES = 5; private static final double SEARCH_RADIUS_METERS = 100.0; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // Retrieve location and camera position from saved instance state. if (savedInstanceState != null) { lastKnownLocation = savedInstanceState.getParcelable(KEY_LOCATION); cameraPosition = savedInstanceState.getParcelable(KEY_CAMERA_POSITION); } // Retrieve the content view that renders the map. setContentView(R.layout.activity_maps); ViewCompat.setOnApplyWindowInsetsListener( getWindow().getDecorView(), (v, insets) -> { Insets systemBars = insets.getInsets( WindowInsetsCompat.Type.systemBars() | WindowInsetsCompat.Type.displayCutout()); View actionBarContainer = getWindow() .getDecorView() .findViewById(androidx.appcompat.R.id.action_bar_container); if (actionBarContainer != null) { actionBarContainer.setPadding( actionBarContainer.getPaddingLeft(), systemBars.top, actionBarContainer.getPaddingRight(), actionBarContainer.getPaddingBottom()); } TypedValue typedValue = new TypedValue(); int actionBarHeight = getTheme() .resolveAttribute( android.R.attr.actionBarSize, typedValue, true) ? TypedValue.complexToDimensionPixelSize( typedValue.data, getResources().getDisplayMetrics()) : 0; if (map != null) { map.setPadding(0, systemBars.top + actionBarHeight, 0, systemBars.bottom); } return insets; }); // Construct a PlacesClient Places.initializeWithNewPlacesApiEnabled(getApplicationContext(), BuildConfig.MAPS_API_KEY); placesClient = Places.createClient(this); // Construct a FusedLocationProviderClient. fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this); // Build the map. SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map); mapFragment.getMapAsync(this); } /** Saves the state of the map when the activity is paused. */ @Override protected void onSaveInstanceState(Bundle outState) { if (map != null) { outState.putParcelable(KEY_CAMERA_POSITION, map.getCameraPosition()); outState.putParcelable(KEY_LOCATION, lastKnownLocation); } super.onSaveInstanceState(outState); } /** * Sets up the options menu. * * @param menu The options menu. * @return Boolean. */ @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.current_place_menu, menu); return true; } /** * Handles a click on the menu option to get a place. * * @param item The menu item to handle. * @return Boolean. */ @Override public boolean onOptionsItemSelected(MenuItem item) { if (item.getItemId() == R.id.option_get_place) { showCurrentPlace(); } return true; } /** * Manipulates the map when it's available. This callback is triggered when the map is ready to * be used. */ @Override public void onMapReady(GoogleMap map) { this.map = map; // Use a custom info window adapter to handle multiple lines of text in the // info window contents. this.map.setInfoWindowAdapter( new GoogleMap.InfoWindowAdapter() { @Override // Return null here, so that getInfoContents() is called next. public View getInfoWindow(Marker arg0) { return null; } @Override public View getInfoContents(Marker marker) { // Inflate the layouts for the info window, title and snippet. View infoWindow = getLayoutInflater() .inflate( R.layout.custom_info_contents, (FrameLayout) findViewById(R.id.map), false); TextView title = infoWindow.findViewById(R.id.title); title.setText(marker.getTitle()); TextView snippet = infoWindow.findViewById(R.id.snippet); snippet.setText(marker.getSnippet()); return infoWindow; } }); // Allow moving the current location with a long press on the map to easily // demo and discover nearby places anywhere in the world. this.map.setOnMapLongClickListener(this::setCustomLocation); // Prompt the user for permission. getLocationPermission(); WindowInsetsCompat rootInsets = ViewCompat.getRootWindowInsets(getWindow().getDecorView()); if (rootInsets != null) { Insets systemBars = rootInsets.getInsets( WindowInsetsCompat.Type.systemBars() | WindowInsetsCompat.Type.displayCutout()); TypedValue typedValue = new TypedValue(); int actionBarHeight = getTheme().resolveAttribute(android.R.attr.actionBarSize, typedValue, true) ? TypedValue.complexToDimensionPixelSize( typedValue.data, getResources().getDisplayMetrics()) : 0; this.map.setPadding(0, systemBars.top + actionBarHeight, 0, systemBars.bottom); } // Turn on the My Location layer and the related control on the map. updateLocationUI(); // Get the current location of the device and set the position of the map. getDeviceLocation(); } /** Gets the current location of the device, and positions the map's camera. */ private void getDeviceLocation() { /* * Get the best and most recent location of the device, which may be null in rare * cases when a location is not available. */ try { if (locationPermissionGranted) { Task<Location> locationResult = fusedLocationProviderClient.getLastLocation(); locationResult.addOnCompleteListener( this, new OnCompleteListener<Location>() { @Override public void onComplete(@NonNull Task<Location> task) { if (task.isSuccessful()) { // Set the map's camera position to the current location of the // device. lastKnownLocation = task.getResult(); if (lastKnownLocation != null) { map.moveCamera( CameraUpdateFactory.newLatLngZoom( new LatLng( lastKnownLocation.getLatitude(), lastKnownLocation.getLongitude()), DEFAULT_ZOOM)); } } else { Log.d(TAG, "Current location is null. Using defaults."); Log.e(TAG, "Exception: %s", task.getException()); map.moveCamera( CameraUpdateFactory.newLatLngZoom( defaultLocation, DEFAULT_ZOOM)); map.getUiSettings().setMyLocationButtonEnabled(false); } } }); } } catch (SecurityException e) { Log.e("Exception: %s", e.getMessage(), e); } } /** Prompts the user for permission to use the device location. */ private void getLocationPermission() { /* * Request location permission, so that we can get the location of the * device. The result of the permission request is handled by a callback, * onRequestPermissionsResult. */ if (ContextCompat.checkSelfPermission( this.getApplicationContext(), android.Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { locationPermissionGranted = true; } else { ActivityCompat.requestPermissions( this, new String[] {android.Manifest.permission.ACCESS_FINE_LOCATION}, PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION); } } /** Handles the result of the request for location permissions. */ @Override public void onRequestPermissionsResult( int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) { locationPermissionGranted = false; if (requestCode == PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION) { // If request is cancelled, the // result arrays are empty. if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { locationPermissionGranted = true; } } else { super.onRequestPermissionsResult(requestCode, permissions, grantResults); } updateLocationUI(); } /** * UI representation of a place item to display in the selection dialog and map marker. * * <p>It is good practice to decouple the external data/backend model ({@link Place}) from the * UI layer. The UI should be as free of logic as possible: it receives presentation-ready data * (non-null coordinates, ready-to-display title and snippet strings) so that dialogs and map * overlays remain simple, predictable, and testable. */ static class PlaceItemUiModel { final String title; final String snippet; final LatLng position; PlaceItemUiModel(String title, String snippet, LatLng position) { this.title = title; this.snippet = snippet; this.position = position; } } /** * Maps an external {@link Place} domain model into a display-ready {@link PlaceItemUiModel}. * * <p>The mapper encapsulates all data normalization, default value fallbacks (such as fallback * titles), and string formatting (such as appending third-party attributions to the address). * Keeping this transformation logic in the mapper prevents business and formatting logic from * leaking into the UI components. Returns {@code null} if essential coordinates are missing. */ private PlaceItemUiModel toUiModel(Place place) { return toUiModel(place, getString(R.string.default_info_title)); } static PlaceItemUiModel toUiModel(Place place, String defaultTitle) { if (place.getLocation() == null) { return null; } String title = place.getDisplayName() != null ? place.getDisplayName() : defaultTitle; StringBuilder snippet = new StringBuilder(); if (place.getFormattedAddress() != null) { snippet.append(place.getFormattedAddress()); } if (place.getAttributions() != null && !place.getAttributions().isEmpty()) { if (snippet.length() > 0) { snippet.append("\n"); } snippet.append(String.join("\n", place.getAttributions())); } return new PlaceItemUiModel(title, snippet.toString(), place.getLocation()); } /** * Prompts the user to select the current place from a list of likely places, and shows the * current place on the map - provided the user has granted location permission. */ private void showCurrentPlace() { if (map == null) { return; } if (lastKnownLocation != null && "manual".equals(lastKnownLocation.getProvider())) { locationPermissionGranted = true; } if (locationPermissionGranted) { // Use fields to define the data types to return. List<Place.Field> placeFields = Arrays.asList( Place.Field.DISPLAY_NAME, Place.Field.FORMATTED_ADDRESS, Place.Field.LOCATION); // Search around the device's last-known location, falling back to the center of the // map if the location is not available yet. LatLng center = lastKnownLocation != null ? new LatLng( lastKnownLocation.getLatitude(), lastKnownLocation.getLongitude()) : map.getCameraPosition().target; CircularBounds searchArea = CircularBounds.newInstance(center, SEARCH_RADIUS_METERS); // Use the builder to create a SearchNearbyRequest that returns the closest places // first. SearchNearbyRequest request = SearchNearbyRequest.builder(searchArea, placeFields) .setMaxResultCount(M_MAX_ENTRIES) .setRankPreference(SearchNearbyRequest.RankPreference.DISTANCE) .build(); // Get the likely places - that is, the businesses and other points of interest that // are closest to the device's current location. final Task<SearchNearbyResponse> placeResult = placesClient.searchNearby(request); placeResult.addOnCompleteListener( new OnCompleteListener<SearchNearbyResponse>() { @Override public void onComplete(@NonNull Task<SearchNearbyResponse> task) { if (task.isSuccessful() && task.getResult() != null) { List<Place> responsePlaces = task.getResult().getPlaces(); int count = Math.min(responsePlaces.size(), M_MAX_ENTRIES); List<PlaceItemUiModel> likelyPlaces = new ArrayList<>(); for (int i = 0; i < count; i++) { PlaceItemUiModel model = toUiModel(responsePlaces.get(i)); if (model != null) { likelyPlaces.add(model); } } // Show a dialog offering the user the list of likely places, and // add a marker at the selected place. MapsActivityCurrentPlace.this.openPlacesDialog(likelyPlaces); } else { Log.e(TAG, "Exception: %s", task.getException()); } } }); } else { // The user has not granted permission. Log.i(TAG, "The user did not grant location permission."); // Add a default marker, because the user hasn't selected a place. map.addMarker( new MarkerOptions() .title(getString(R.string.default_info_title)) .position(defaultLocation) .snippet(getString(R.string.default_info_snippet))); // Prompt the user for permission. getLocationPermission(); } } /** Displays a form allowing the user to select a place from a list of likely places. */ void openPlacesDialog(List<PlaceItemUiModel> likelyPlaces) { if (likelyPlaces.isEmpty()) { Toast.makeText( this, "No places found nearby. Long-press on the map to choose another location.", Toast.LENGTH_LONG) .show(); return; } // Ask the user to choose the place where they are now. DialogInterface.OnClickListener listener = new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { // The "which" argument contains the position of the selected item. PlaceItemUiModel selectedPlace = likelyPlaces.get(which); // Add a marker for the selected place, with an info window // showing information about that place. map.addMarker( new MarkerOptions() .title(selectedPlace.title) .position(selectedPlace.position) .snippet(selectedPlace.snippet)); // Position the map's camera at the location of the marker. map.moveCamera( CameraUpdateFactory.newLatLngZoom( selectedPlace.position, DEFAULT_ZOOM)); } }; // Display the dialog. String[] titles = new String[likelyPlaces.size()]; for (int i = 0; i < likelyPlaces.size(); i++) { titles[i] = likelyPlaces.get(i).title; } new AlertDialog.Builder(this) .setTitle(R.string.pick_place) .setItems(titles, listener) .show(); } /** Updates the map's UI settings based on whether the user has granted location permission. */ private void updateLocationUI() { if (map == null) { return; } try { if (locationPermissionGranted) { map.setMyLocationEnabled(true); map.getUiSettings().setMyLocationButtonEnabled(true); } else { map.setMyLocationEnabled(false); map.getUiSettings().setMyLocationButtonEnabled(false); lastKnownLocation = null; } } catch (SecurityException e) { Log.e("Exception: %s", e.getMessage()); } } /** Updates the current location and searches for places around the specified coordinate. */ void setCustomLocation(LatLng latLng) { Location location = new Location("manual"); location.setLatitude(latLng.latitude); location.setLongitude(latLng.longitude); lastKnownLocation = location; if (map != null) { map.animateCamera(CameraUpdateFactory.newLatLng(latLng)); } showCurrentPlace(); } }
Consulta la versión de Kotlin de la actividad:
// Copyright 2020 Google LLC // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. package com.example.currentplacedetailsonmap import android.Manifest import android.annotation.SuppressLint import android.content.DialogInterface import android.content.pm.PackageManager import android.location.Location import android.os.Bundle import android.util.Log import android.util.TypedValue import android.view.Menu import android.view.MenuItem import android.view.View import android.widget.FrameLayout import android.widget.TextView import android.widget.Toast import androidx.appcompat.app.AlertDialog import androidx.appcompat.app.AppCompatActivity import androidx.core.app.ActivityCompat import androidx.core.content.ContextCompat import androidx.core.view.ViewCompat import androidx.core.view.WindowInsetsCompat import com.google.android.gms.location.FusedLocationProviderClient import com.google.android.gms.location.LocationServices import com.google.android.gms.maps.CameraUpdateFactory import com.google.android.gms.maps.GoogleMap import com.google.android.gms.maps.GoogleMap.InfoWindowAdapter import com.google.android.gms.maps.OnMapReadyCallback import com.google.android.gms.maps.SupportMapFragment import com.google.android.gms.maps.model.CameraPosition import com.google.android.gms.maps.model.LatLng import com.google.android.gms.maps.model.Marker import com.google.android.gms.maps.model.MarkerOptions import com.google.android.libraries.places.api.Places import com.google.android.libraries.places.api.model.CircularBounds import com.google.android.libraries.places.api.model.Place import com.google.android.libraries.places.api.net.PlacesClient import com.google.android.libraries.places.api.net.SearchNearbyRequest /** * An activity that displays a map showing the place at the device's current location. */ class MapsActivityCurrentPlace : AppCompatActivity(), OnMapReadyCallback { private var map: GoogleMap? = null private var cameraPosition: CameraPosition? = null internal var selectedMarker: Marker? = null // The entry point to the Places API. private lateinit var placesClient: PlacesClient // The entry point to the Fused Location Provider. private lateinit var fusedLocationProviderClient: FusedLocationProviderClient // A default location (Sydney, Australia) and default zoom to use when location permission is // not granted. private val defaultLocation = LatLng(-33.8523341, 151.2106085) private var locationPermissionGranted = false // The geographical location where the device is currently located. That is, the last-known // location retrieved by the Fused Location Provider or set via long press. internal var lastKnownLocation: Location? = null override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) // Retrieve location and camera position from saved instance state. if (savedInstanceState != null) { lastKnownLocation = savedInstanceState.getParcelable(KEY_LOCATION) cameraPosition = savedInstanceState.getParcelable(KEY_CAMERA_POSITION) } // Retrieve the content view that renders the map. setContentView(R.layout.activity_maps) ViewCompat.setOnApplyWindowInsetsListener(window.decorView) { _, insets -> val systemBars = insets.getInsets( WindowInsetsCompat.Type.systemBars() or WindowInsetsCompat.Type.displayCutout(), ) val actionBarContainer = window.decorView.findViewById<View>(androidx.appcompat.R.id.action_bar_container) actionBarContainer?.setPadding( actionBarContainer.paddingLeft, systemBars.top, actionBarContainer.paddingRight, actionBarContainer.paddingBottom, ) val typedValue = TypedValue() val actionBarHeight = if (theme.resolveAttribute(android.R.attr.actionBarSize, typedValue, true)) { TypedValue.complexToDimensionPixelSize(typedValue.data, resources.displayMetrics) } else { 0 } map?.setPadding(0, systemBars.top + actionBarHeight, 0, systemBars.bottom) insets } // Construct a PlacesClient Places.initializeWithNewPlacesApiEnabled(applicationContext, BuildConfig.MAPS_API_KEY) placesClient = Places.createClient(this) // Construct a FusedLocationProviderClient. fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this) // Build the map. val mapFragment = supportFragmentManager .findFragmentById(R.id.map) as SupportMapFragment? mapFragment?.getMapAsync(this) } /** * Saves the state of the map when the activity is paused. */ override fun onSaveInstanceState(outState: Bundle) { map?.let { map -> outState.putParcelable(KEY_CAMERA_POSITION, map.cameraPosition) outState.putParcelable(KEY_LOCATION, lastKnownLocation) } super.onSaveInstanceState(outState) } /** * Sets up the options menu. * @param menu The options menu. * @return Boolean. */ override fun onCreateOptionsMenu(menu: Menu): Boolean { menuInflater.inflate(R.menu.current_place_menu, menu) return true } /** * Handles a click on the menu option to get a place. * @param item The menu item to handle. * @return Boolean. */ override fun onOptionsItemSelected(item: MenuItem): Boolean { if (item.itemId == R.id.option_get_place) { showCurrentPlace() } return true } /** * Manipulates the map when it's available. * This callback is triggered when the map is ready to be used. */ override fun onMapReady(map: GoogleMap) { this.map = map // Use a custom info window adapter to handle multiple lines of text in the // info window contents. this.map?.setInfoWindowAdapter(object : InfoWindowAdapter { // Return null here, so that getInfoContents() is called next. override fun getInfoWindow(arg0: Marker): View? = null override fun getInfoContents(marker: Marker): View { // Inflate the layouts for the info window, title and snippet. val infoWindow = layoutInflater.inflate( R.layout.custom_info_contents, findViewById<FrameLayout>(R.id.map), false, ) val title = infoWindow.findViewById<TextView>(R.id.title) title.text = marker.title val snippet = infoWindow.findViewById<TextView>(R.id.snippet) snippet.text = marker.snippet return infoWindow } }) // Allow moving the current location with a long press on the map to easily // demo and discover nearby places anywhere in the world. this.map?.setOnMapLongClickListener { latLng -> setCustomLocation(latLng) } // Prompt the user for permission. getLocationPermission() val insets = ViewCompat.getRootWindowInsets(window.decorView) ?.getInsets(WindowInsetsCompat.Type.systemBars() or WindowInsetsCompat.Type.displayCutout()) val topInset = insets?.top ?: 0 val bottomInset = insets?.bottom ?: 0 val typedValue = TypedValue() val actionBarHeight = if (theme.resolveAttribute(android.R.attr.actionBarSize, typedValue, true)) { TypedValue.complexToDimensionPixelSize(typedValue.data, resources.displayMetrics) } else { 0 } this.map?.setPadding(0, topInset + actionBarHeight, 0, bottomInset) // Turn on the My Location layer and the related control on the map. updateLocationUI() // Get the current location of the device and set the position of the map. getDeviceLocation() } /** * Gets the current location of the device, and positions the map's camera. */ @SuppressLint("MissingPermission") private fun getDeviceLocation() { /* * Get the best and most recent location of the device, which may be null in rare * cases when a location is not available. */ try { if (locationPermissionGranted) { val locationResult = fusedLocationProviderClient.lastLocation locationResult.addOnCompleteListener(this) { task -> if (task.isSuccessful) { // Set the map's camera position to the current location of the device. lastKnownLocation = task.result if (lastKnownLocation != null) { map?.moveCamera( CameraUpdateFactory.newLatLngZoom( LatLng( lastKnownLocation!!.latitude, lastKnownLocation!!.longitude, ), DEFAULT_ZOOM.toFloat(), ), ) } } else { Log.d(TAG, "Current location is null. Using defaults.") Log.e(TAG, "Exception: %s", task.exception) map?.moveCamera( CameraUpdateFactory .newLatLngZoom(defaultLocation, DEFAULT_ZOOM.toFloat()), ) map?.uiSettings?.isMyLocationButtonEnabled = false } } } } catch (e: SecurityException) { Log.e("Exception: %s", e.message, e) } } /** * Prompts the user for permission to use the device location. */ private fun getLocationPermission() { /* * Request location permission, so that we can get the location of the * device. The result of the permission request is handled by a callback, * onRequestPermissionsResult. */ if (ContextCompat.checkSelfPermission( this.applicationContext, Manifest.permission.ACCESS_FINE_LOCATION, ) == PackageManager.PERMISSION_GRANTED ) { locationPermissionGranted = true } else { ActivityCompat.requestPermissions( this, arrayOf(Manifest.permission.ACCESS_FINE_LOCATION), PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION, ) } } /** * Handles the result of the request for location permissions. */ override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String>, grantResults: IntArray) { locationPermissionGranted = false when (requestCode) { PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION -> { // If request is cancelled, the result arrays are empty. if (grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED ) { locationPermissionGranted = true } } else -> super.onRequestPermissionsResult(requestCode, permissions, grantResults) } updateLocationUI() } private fun Place.toUiModel(): PlaceItemUiModel? = toPlaceItemUiModel(this, getString(R.string.default_info_title)) /** * Prompts the user to select the current place from a list of likely places, and shows the * current place on the map - provided the user has granted location permission. */ private fun showCurrentPlace() { val map = map ?: return if (lastKnownLocation?.provider == "manual") { locationPermissionGranted = true } if (locationPermissionGranted) { // Use fields to define the data types to return. val placeFields = listOf( Place.Field.DISPLAY_NAME, Place.Field.FORMATTED_ADDRESS, Place.Field.LOCATION, ) // Search around the device's last-known location, falling back to the center of // the map if the location is not available yet. val center = lastKnownLocation?.let { LatLng(it.latitude, it.longitude) } ?: map.cameraPosition.target val searchArea = CircularBounds.newInstance(center, SEARCH_RADIUS_METERS) // Use the builder to create a SearchNearbyRequest that returns the closest places // first. val request = SearchNearbyRequest.builder(searchArea, placeFields) .setMaxResultCount(M_MAX_ENTRIES) .setRankPreference(SearchNearbyRequest.RankPreference.DISTANCE) .build() // Get the likely places - that is, the businesses and other points of interest that // are closest to the device's current location. val placeResult = placesClient.searchNearby(request) placeResult.addOnCompleteListener { task -> if (task.isSuccessful && task.result != null) { val likelyPlaces = task.result.places .take(M_MAX_ENTRIES) .mapNotNull { it.toUiModel() } // Show a dialog offering the user the list of likely places, and add a // marker at the selected place. openPlacesDialog(likelyPlaces) } else { Log.e(TAG, "Exception: %s", task.exception) } } } else { // The user has not granted permission. Log.i(TAG, "The user did not grant location permission.") // Add a default marker, because the user hasn't selected a place. map.addMarker( MarkerOptions() .title(getString(R.string.default_info_title)) .position(defaultLocation) .snippet(getString(R.string.default_info_snippet)), ) // Prompt the user for permission. getLocationPermission() } } /** * Displays a form allowing the user to select a place from a list of likely places. */ internal fun openPlacesDialog(likelyPlaces: List<PlaceItemUiModel>) { if (likelyPlaces.isEmpty()) { Toast.makeText( this, "No places found nearby. Long-press on the map to choose another location.", Toast.LENGTH_LONG, ).show() return } // Ask the user to choose the place where they are now. val listener = DialogInterface.OnClickListener { _, which -> // The "which" argument contains the position of the selected item. val selectedPlace = likelyPlaces[which] // Add a marker for the selected place, with an info window // showing information about that place. selectedMarker = map?.addMarker( MarkerOptions() .title(selectedPlace.title) .position(selectedPlace.position) .snippet(selectedPlace.snippet), ) // Position the map's camera at the location of the marker. map?.moveCamera( CameraUpdateFactory.newLatLngZoom( selectedPlace.position, DEFAULT_ZOOM.toFloat(), ), ) } // Display the dialog. val titles = likelyPlaces.map { it.title }.toTypedArray() AlertDialog.Builder(this) .setTitle(R.string.pick_place) .setItems(titles, listener) .show() } /** * Updates the map's UI settings based on whether the user has granted location permission. */ @SuppressLint("MissingPermission") private fun updateLocationUI() { if (map == null) { return } try { if (locationPermissionGranted) { map?.isMyLocationEnabled = true map?.uiSettings?.isMyLocationButtonEnabled = true } else { map?.isMyLocationEnabled = false map?.uiSettings?.isMyLocationButtonEnabled = false lastKnownLocation = null getLocationPermission() } } catch (e: SecurityException) { Log.e("Exception: %s", e.message, e) } } /** * Updates the current location and searches for places around the specified coordinate. */ internal fun setCustomLocation(latLng: LatLng) { val location = Location("manual").apply { latitude = latLng.latitude longitude = latLng.longitude } lastKnownLocation = location map?.animateCamera(CameraUpdateFactory.newLatLng(latLng)) showCurrentPlace() } companion object { private val TAG = MapsActivityCurrentPlace::class.java.simpleName private const val DEFAULT_ZOOM = 15 private const val PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION = 1 // Keys for storing activity state. private const val KEY_CAMERA_POSITION = "camera_position" private const val KEY_LOCATION = "location" // Used for selecting the current place. private const val M_MAX_ENTRIES = 5 private const val SEARCH_RADIUS_METERS = 100.0 } } /** * UI representation of a place item to display in the selection dialog and map marker. * * It is good practice to decouple the external data/backend model ([Place]) from the UI layer. * The UI should be as free of logic as possible: it receives presentation-ready data (non-null * coordinates, ready-to-display title and snippet strings) so that dialogs and map overlays * remain simple, predictable, and testable. */ internal data class PlaceItemUiModel(val title: String, val snippet: String, val position: LatLng) /** * Maps an external [Place] domain model into a display-ready [PlaceItemUiModel]. * * The mapper encapsulates all data normalization, default value fallbacks (such as fallback * titles), and string formatting (such as appending third-party attributions to the address). * Keeping this transformation logic in the mapper prevents business and formatting logic * from leaking into the UI components. Returns `null` if essential coordinates are missing. */ internal fun toPlaceItemUiModel(place: Place, defaultTitle: String): PlaceItemUiModel? { val position = place.location ?: return null val title = place.displayName ?: defaultTitle val snippet = buildString { place.formattedAddress?.let { append(it) } place.attributions?.takeIf { it.isNotEmpty() }?.let { if (isNotEmpty()) append("\n") append(it.joinToString("\n")) } } return PlaceItemUiModel(title = title, snippet = snippet, position = position) }
Configura tu proyecto de desarrollo
Sigue estos pasos para crear el proyecto del instructivo en Android Studio:
- Descarga Android Studio y, luego, instálalo.
- Agrega el paquete de los Servicios de Google Play a Android Studio.
- Clona o descarga el repositorio de muestras de la versión 2 de la API de Google Maps para Android si no lo hiciste cuando empezaste a leer este instructivo.
Importa el proyecto del instructivo:
- En Android Studio, selecciona File > New > Import Project.
- Ve a la ubicación en que guardaste el repositorio de muestras de la versión 2 de la API de Google Maps para Android tras descargarlo.
- Busca el proyecto CurrentPlaceDetailsOnMap en esta ubicación:
PATH-TO-SAVED-REPO/android-samples/tutorials/java/CurrentPlaceDetailsOnMap(Java) o
PATH-TO-SAVED-REPO/android-samples/tutorials/kotlin/CurrentPlaceDetailsOnMap(Kotlin). - Selecciona el directorio del proyecto y haz clic en Open. Android Studio ahora creará tu proyecto con la herramienta de compilación Gradle.
Habilita las APIs necesarias y obtén una clave de API
Para completar este instructivo, necesitas un proyecto de Google Cloud con las APIs necesarias habilitadas y una clave de API autorizada para utilizar el SDK de Maps para Android. Para obtener más información, consulta los siguientes recursos:
Para ver las APIs que habilitaste, ve a la página de Google Maps Platform en la consola de Cloud y selecciona tu proyecto:
Ir a la página de Google Maps PlatformSi la API de Places no aparece habilitada para tu proyecto, debes habilitarla:
Habilitar la API de PlacesSi agregas restricciones a tu clave de API, asegúrate de agregar la API de Places a la clave. Consulta Cómo usar claves de API para obtener más información.
Agrega la clave de API a tu app
- Abre el archivo
local.propertiesde tu proyecto. Agrega la siguiente cadena y, luego, reemplaza
YOUR_API_KEYpor el valor de tu clave de API:MAPS_API_KEY=YOUR_API_KEY
Cuando compiles tu app, el complemento Secrets Gradle para Android copiará la clave de API y la pondrá a disposición como una variable de compilación en el manifiesto de Android.
Compila y ejecuta tu app
Conecta un dispositivo Android a tu computadora. Sigue las instrucciones para habilitar las opciones para desarrolladores en tu dispositivo Android y configurar el sistema para que lo detecte.
También puedes utilizar el Administrador de dispositivos virtuales de Android (AVD) para configurar esos dispositivos. Cuando elijas un emulador, asegúrate de seleccionar una imagen que incluya las APIs de Google. Para obtener más detalles, consulta Configura un proyecto de Android Studio.
- En Android Studio, haz clic en la opción Run del menú (o en el ícono del botón de reproducción). Selecciona un dispositivo cuando se solicite.
Android Studio invoca a Gradle para compilar la app y, luego, la ejecuta en el dispositivo o el emulador. Deberías ver un mapa con una serie de marcadores centrados cerca de tu ubicación actual, similar al de la imagen incluida en esta página.
- Selecciona Get Place para abrir una lista de lugares (una empresa o cualquier lugar de interés) cerca de tu ubicación actual. Para ver la lista de lugares, debes otorgar el permiso de ubicación cuando se te solicite.
- Selecciona un lugar de la lista. Se agrega un marcador al lugar seleccionado en el mapa.
Solución de problemas:
- Si no ves un mapa, verifica si obtuviste una clave de API y la agregaste a la app, como se describió anteriormente. Consulta el registro en Android Monitor de Android Studio para ver si hay mensajes de error acerca de la clave de API.
- Si el mapa muestra solo un marcador ubicado en el Puente de la Bahía de Sídney (la ubicación predeterminada que se especificó en la app), verifica que le otorgaste permiso de ubicación a la app. Esta solicita ese permiso en el tiempo de ejecución, según el patrón descrito en la guía sobre permisos de Android. Ten en cuenta que también puedes configurar los permisos directamente en el dispositivo. Para ello, selecciona Configuración > Apps > nombre de la app > Permisos > Ubicación. Para obtener detalles sobre cómo controlar los permisos en tu código, consulta la guía que se incluye a continuación sobre cómo solicitar permisos de ubicación en tu app.
- Utiliza las herramientas de depuración de Android Studio para ver los registros y depurar la app.
Comprende el código
En esta sección del instructivo, se explican los componentes más importantes de la app CurrentPlaceDetailsOnMap para ayudarte a comprender cómo compilar una app similar.
Crea una instancia de cliente de la API de Places
Los siguientes objetos son los principales puntos de entrada del SDK de Places para Android:
- La clase
Placescrea y administra clientes para el SDK de Places para Android. - La interfaz
PlacesClientrecupera la ubicación actual del dispositivo y los lugares cercanos a ella.
La interfaz LocationServices es el principal punto de entrada para los Servicios de ubicación de Android.
Para usar las APIs, haz lo siguiente en el método onCreate() de tu fragmento o actividad:
- Inicializa un objeto
Places. - Crea un objeto
PlacesClient. - Crea un objeto
FusedLocationProviderClient.
Por ejemplo:
Java
@Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // ... // Retrieve the content view that renders the map. setContentView(R.layout.activity_maps); // Construct a PlacesClient Places.initialize(getApplicationContext(), getString(R.string.maps_api_key)); placesClient = Places.createClient(this); // Construct a FusedLocationProviderClient. fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this); }
Kotlin
override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) // ... // Retrieve the content view that renders the map. setContentView(R.layout.activity_maps) // Construct a PlacesClient Places.initialize(applicationContext, getString(R.string.maps_api_key)) placesClient = Places.createClient(this) // Construct a FusedLocationProviderClient. fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this) }
Solicita un permiso de ubicación
Tu app debe solicitar permiso de ubicación para determinar la ubicación del dispositivo y permitir que el usuario presione el botón Mi ubicación en el mapa.
En este instructivo, se proporciona el código necesario para solicitar el permiso de ubicación precisa. Para obtener más detalles, consulta la guía sobre permisos de Android.
Agrega el permiso como componente secundario del elemento
<manifest>en tu manifiesto de Android:<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.currentplacedetailsonmap"> <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> </manifest>
En tu app, solicita permisos de tiempo de ejecución para que el usuario pueda autorizar o rechazar el permiso de ubicación. El siguiente código verifica si el usuario otorgó el permiso de ubicación precisa y, si no lo hizo, se lo solicita:
Java
private void getLocationPermission() { /* * Request location permission, so that we can get the location of the * device. The result of the permission request is handled by a callback, * onRequestPermissionsResult. */ if (ContextCompat.checkSelfPermission( this.getApplicationContext(), android.Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) { locationPermissionGranted = true; } else { ActivityCompat.requestPermissions( this, new String[] {android.Manifest.permission.ACCESS_FINE_LOCATION}, PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION); } }
Kotlin
private fun getLocationPermission() { /* * Request location permission, so that we can get the location of the * device. The result of the permission request is handled by a callback, * onRequestPermissionsResult. */ if (ContextCompat.checkSelfPermission( this.applicationContext, Manifest.permission.ACCESS_FINE_LOCATION, ) == PackageManager.PERMISSION_GRANTED ) { locationPermissionGranted = true } else { ActivityCompat.requestPermissions( this, arrayOf(Manifest.permission.ACCESS_FINE_LOCATION), PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION, ) } }
Anula la devolución de llamada
onRequestPermissionsResult()para controlar el resultado de la solicitud de permiso:Java
@Override public void onRequestPermissionsResult( int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) { locationPermissionGranted = false; if (requestCode == PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION) { // If request is cancelled, the // result arrays are empty. if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { locationPermissionGranted = true; } } else { super.onRequestPermissionsResult(requestCode, permissions, grantResults); } updateLocationUI(); }
Kotlin
override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String>, grantResults: IntArray) { locationPermissionGranted = false when (requestCode) { PERMISSIONS_REQUEST_ACCESS_FINE_LOCATION -> { // If request is cancelled, the result arrays are empty. if (grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED ) { locationPermissionGranted = true } } else -> super.onRequestPermissionsResult(requestCode, permissions, grantResults) } updateLocationUI() }
Más adelante en este instructivo se describe el método
updateLocationUI().
Agrega un mapa
Muestra un mapa con el SDK de Maps para Android.
Agrega un elemento
<fragment>al archivo de diseño de tu actividad,activity_maps.xml. Este elemento define un fragmentoSupportMapFragmentpara que actúe como contenedor del mapa y proporcione acceso al objetoGoogleMap. En el instructivo, se utiliza la versión de la biblioteca de compatibilidad de Android correspondiente al fragmento de mapa para garantizar la retrocompatibilidad con las versiones anteriores del framework de Android.<!-- Copyright 2020 Google LLC Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <fragment xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/map" android:name="com.google.android.gms.maps.SupportMapFragment" android:layout_width="match_parent" android:layout_height="match_parent" tools:context="com.example.currentplacedetailsonmap.MapsActivityCurrentPlace" />
En el método
onCreate()de tu actividad, establece el archivo de diseño como la vista de contenido:Java
@Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // Retrieve the content view that renders the map. setContentView(R.layout.activity_maps); }
Kotlin
override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) // Retrieve the content view that renders the map. setContentView(R.layout.activity_maps) }
Implementa la interfaz
OnMapReadyCallbacky anula el métodoonMapReady()para configurar el mapa cuando el objetoGoogleMapesté disponible:Java
@Override public void onMapReady(GoogleMap map) { this.map = map; // ... // Turn on the My Location layer and the related control on the map. updateLocationUI(); // Get the current location of the device and set the position of the map. getDeviceLocation(); }
Kotlin
override fun onMapReady(map: GoogleMap) { this.map = map // ... // Turn on the My Location layer and the related control on the map. updateLocationUI() // Get the current location of the device and set the position of the map. getDeviceLocation() }
En el método
onCreate()de tu actividad, llama aFragmentManager.findFragmentById()para controlar el fragmento de mapa. Luego, utilizagetMapAsync()para registrarte para la devolución de llamada del mapa:Java
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map); mapFragment.getMapAsync(this);
Kotlin
val mapFragment = supportFragmentManager .findFragmentById(R.id.map) as SupportMapFragment? mapFragment?.getMapAsync(this)
Escribe un método
updateLocationUI()para establecer los controles de ubicación en el mapa. Si el usuario otorgó permisos de ubicación, habilita la capa Mi ubicación y el control relacionado en el mapa. De lo contrario, inhabilítalos y establece la ubicación actual en null:Java
private void updateLocationUI() { if (map == null) { return; } try { if (locationPermissionGranted) { map.setMyLocationEnabled(true); map.getUiSettings().setMyLocationButtonEnabled(true); } else { map.setMyLocationEnabled(false); map.getUiSettings().setMyLocationButtonEnabled(false); lastKnownLocation = null; } } catch (SecurityException e) { Log.e("Exception: %s", e.getMessage()); } }
Kotlin
@SuppressLint("MissingPermission") private fun updateLocationUI() { if (map == null) { return } try { if (locationPermissionGranted) { map?.isMyLocationEnabled = true map?.uiSettings?.isMyLocationButtonEnabled = true } else { map?.isMyLocationEnabled = false map?.uiSettings?.isMyLocationButtonEnabled = false lastKnownLocation = null getLocationPermission() } } catch (e: SecurityException) { Log.e("Exception: %s", e.message, e) } }
Obtén la ubicación del dispositivo Android y posiciona el mapa
Utiliza el proveedor de ubicación combinada para buscar la última ubicación conocida del dispositivo y, luego, posiciona el mapa en función de esa ubicación. En este instructivo, se proporciona el código necesario. Para obtener más detalles sobre cómo obtener la ubicación del dispositivo, consulta la guía del proveedor de ubicación combinada en las APIs de ubicación de los Servicios de Google Play.
Java
private void getDeviceLocation() { /* * Get the best and most recent location of the device, which may be null in rare * cases when a location is not available. */ try { if (locationPermissionGranted) { Task<Location> locationResult = fusedLocationProviderClient.getLastLocation(); locationResult.addOnCompleteListener( this, new OnCompleteListener<Location>() { @Override public void onComplete(@NonNull Task<Location> task) { if (task.isSuccessful()) { // Set the map's camera position to the current location of the // device. lastKnownLocation = task.getResult(); if (lastKnownLocation != null) { map.moveCamera( CameraUpdateFactory.newLatLngZoom( new LatLng( lastKnownLocation.getLatitude(), lastKnownLocation.getLongitude()), DEFAULT_ZOOM)); } } else { Log.d(TAG, "Current location is null. Using defaults."); Log.e(TAG, "Exception: %s", task.getException()); map.moveCamera( CameraUpdateFactory.newLatLngZoom( defaultLocation, DEFAULT_ZOOM)); map.getUiSettings().setMyLocationButtonEnabled(false); } } }); } } catch (SecurityException e) { Log.e("Exception: %s", e.getMessage(), e); } }
Kotlin
@SuppressLint("MissingPermission") private fun getDeviceLocation() { /* * Get the best and most recent location of the device, which may be null in rare * cases when a location is not available. */ try { if (locationPermissionGranted) { val locationResult = fusedLocationProviderClient.lastLocation locationResult.addOnCompleteListener(this) { task -> if (task.isSuccessful) { // Set the map's camera position to the current location of the device. lastKnownLocation = task.result if (lastKnownLocation != null) { map?.moveCamera( CameraUpdateFactory.newLatLngZoom( LatLng( lastKnownLocation!!.latitude, lastKnownLocation!!.longitude, ), DEFAULT_ZOOM.toFloat(), ), ) } } else { Log.d(TAG, "Current location is null. Using defaults.") Log.e(TAG, "Exception: %s", task.exception) map?.moveCamera( CameraUpdateFactory .newLatLngZoom(defaultLocation, DEFAULT_ZOOM.toFloat()), ) map?.uiSettings?.isMyLocationButtonEnabled = false } } } } catch (e: SecurityException) { Log.e("Exception: %s", e.message, e) } }
Obtén el lugar actual
Utiliza el SDK de Places para Android para obtener una lista de los posibles lugares en la ubicación actual del dispositivo. En este contexto, un lugar es una empresa o cualquier lugar de interés.
En este instructivo, se muestra cómo obtener el lugar actual cuando el usuario hace clic en el botón Get Place. Ofrece al usuario una lista de los lugares que puede elegir y, luego, agrega un marcador al mapa en la ubicación del lugar seleccionado. En el instructivo, se proporciona el código necesario para interactuar con el SDK de Places para Android. Para obtener más detalles, consulta la guía sobre cómo obtener el lugar actual.
- Crea un archivo de diseño (
current_place_menu.xml) para el menú de opciones y anula el métodoonCreateOptionsMenu()para configurar dicho menú. Consulta la app de ejemplo que se incluye para obtener el código. - Anula el método
onOptionsItemSelected()para obtener el lugar actual cuando el usuario haga clic en la opción Get Place:Java
@Override public boolean onOptionsItemSelected(MenuItem item) { if (item.getItemId() == R.id.option_get_place) { showCurrentPlace(); } return true; }
Kotlin
override fun onOptionsItemSelected(item: MenuItem): Boolean { if (item.itemId == R.id.option_get_place) { showCurrentPlace() } return true }
Crea un método
showCurrentPlace()para obtener una lista de los posibles lugares en la ubicación actual del dispositivo:Java
private void showCurrentPlace() { if (map == null) { return; } // ... if (locationPermissionGranted) { // Use fields to define the data types to return. List<Place.Field> placeFields = Arrays.asList( Place.Field.DISPLAY_NAME, Place.Field.FORMATTED_ADDRESS, Place.Field.LOCATION); // Search around the device's last-known location, falling back to the center of the // map if the location is not available yet. LatLng center = lastKnownLocation != null ? new LatLng( lastKnownLocation.getLatitude(), lastKnownLocation.getLongitude()) : map.getCameraPosition().target; CircularBounds searchArea = CircularBounds.newInstance(center, SEARCH_RADIUS_METERS); // Use the builder to create a SearchNearbyRequest that returns the closest places // first. SearchNearbyRequest request = SearchNearbyRequest.builder(searchArea, placeFields) .setMaxResultCount(M_MAX_ENTRIES) .setRankPreference(SearchNearbyRequest.RankPreference.DISTANCE) .build(); // Get the likely places - that is, the businesses and other points of interest that // are closest to the device's current location. final Task<SearchNearbyResponse> placeResult = placesClient.searchNearby(request); placeResult.addOnCompleteListener( new OnCompleteListener<SearchNearbyResponse>() { @Override public void onComplete(@NonNull Task<SearchNearbyResponse> task) { if (task.isSuccessful() && task.getResult() != null) { List<Place> responsePlaces = task.getResult().getPlaces(); int count = Math.min(responsePlaces.size(), M_MAX_ENTRIES); List<PlaceItemUiModel> likelyPlaces = new ArrayList<>(); for (int i = 0; i < count; i++) { PlaceItemUiModel model = toUiModel(responsePlaces.get(i)); if (model != null) { likelyPlaces.add(model); } } // Show a dialog offering the user the list of likely places, and // add a marker at the selected place. MapsActivityCurrentPlace.this.openPlacesDialog(likelyPlaces); } else { Log.e(TAG, "Exception: %s", task.getException()); } } }); } else { // The user has not granted permission. Log.i(TAG, "The user did not grant location permission."); // Add a default marker, because the user hasn't selected a place. map.addMarker( new MarkerOptions() .title(getString(R.string.default_info_title)) .position(defaultLocation) .snippet(getString(R.string.default_info_snippet))); // Prompt the user for permission. getLocationPermission(); } }
Kotlin
private fun showCurrentPlace() { val map = map ?: return // ... if (locationPermissionGranted) { // Use fields to define the data types to return. val placeFields = listOf( Place.Field.DISPLAY_NAME, Place.Field.FORMATTED_ADDRESS, Place.Field.LOCATION, ) // Search around the device's last-known location, falling back to the center of // the map if the location is not available yet. val center = lastKnownLocation?.let { LatLng(it.latitude, it.longitude) } ?: map.cameraPosition.target val searchArea = CircularBounds.newInstance(center, SEARCH_RADIUS_METERS) // Use the builder to create a SearchNearbyRequest that returns the closest places // first. val request = SearchNearbyRequest.builder(searchArea, placeFields) .setMaxResultCount(M_MAX_ENTRIES) .setRankPreference(SearchNearbyRequest.RankPreference.DISTANCE) .build() // Get the likely places - that is, the businesses and other points of interest that // are closest to the device's current location. val placeResult = placesClient.searchNearby(request) placeResult.addOnCompleteListener { task -> if (task.isSuccessful && task.result != null) { val likelyPlaces = task.result.places .take(M_MAX_ENTRIES) .mapNotNull { it.toUiModel() } // Show a dialog offering the user the list of likely places, and add a // marker at the selected place. openPlacesDialog(likelyPlaces) } else { Log.e(TAG, "Exception: %s", task.exception) } } } else { // The user has not granted permission. Log.i(TAG, "The user did not grant location permission.") // Add a default marker, because the user hasn't selected a place. map.addMarker( MarkerOptions() .title(getString(R.string.default_info_title)) .position(defaultLocation) .snippet(getString(R.string.default_info_snippet)), ) // Prompt the user for permission. getLocationPermission() } }
Crea un método
openPlacesDialog()para mostrar un formulario que permita al usuario seleccionar un lugar de una lista de posibles lugares. Agrega un marcador del lugar seleccionado en el mapa. El contenido del marcador incluirá el nombre y la dirección del lugar, así como las atribuciones que proporciona la API:Java
void openPlacesDialog(List<PlaceItemUiModel> likelyPlaces) { // ... // Ask the user to choose the place where they are now. DialogInterface.OnClickListener listener = new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { // The "which" argument contains the position of the selected item. PlaceItemUiModel selectedPlace = likelyPlaces.get(which); // Add a marker for the selected place, with an info window // showing information about that place. map.addMarker( new MarkerOptions() .title(selectedPlace.title) .position(selectedPlace.position) .snippet(selectedPlace.snippet)); // Position the map's camera at the location of the marker. map.moveCamera( CameraUpdateFactory.newLatLngZoom( selectedPlace.position, DEFAULT_ZOOM)); } }; // Display the dialog. String[] titles = new String[likelyPlaces.size()]; for (int i = 0; i < likelyPlaces.size(); i++) { titles[i] = likelyPlaces.get(i).title; } new AlertDialog.Builder(this) .setTitle(R.string.pick_place) .setItems(titles, listener) .show(); }
Kotlin
internal fun openPlacesDialog(likelyPlaces: List<PlaceItemUiModel>) { // ... // Ask the user to choose the place where they are now. val listener = DialogInterface.OnClickListener { _, which -> // The "which" argument contains the position of the selected item. val selectedPlace = likelyPlaces[which] // Add a marker for the selected place, with an info window // showing information about that place. selectedMarker = map?.addMarker( MarkerOptions() .title(selectedPlace.title) .position(selectedPlace.position) .snippet(selectedPlace.snippet), ) // Position the map's camera at the location of the marker. map?.moveCamera( CameraUpdateFactory.newLatLngZoom( selectedPlace.position, DEFAULT_ZOOM.toFloat(), ), ) } // Display the dialog. val titles = likelyPlaces.map { it.title }.toTypedArray() AlertDialog.Builder(this) .setTitle(R.string.pick_place) .setItems(titles, listener) .show() }
Crea un diseño personalizado para el contenido de la ventana de información. De esta forma, podrás mostrar varias líneas de contenido en esa ventana. Primero, agrega un archivo de diseño XML,
custom_info_contents.xml, que contenga una vista de texto para el título de la ventana de información y otra para el fragmento (es decir, el contenido de texto de la ventana):<?xml version="1.0" encoding="utf-8"?> <!-- Copyright 2020 Google LLC Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layoutDirection="locale" android:orientation="vertical"> <TextView android:id="@+id/title" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_horizontal" android:textColor="#ff000000" android:textStyle="bold" /> <TextView android:id="@+id/snippet" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textColor="#ff7f7f7f" /> </LinearLayout>
Implementa la interfaz
InfoWindowAdapterpara aumentar el diseño y cargar el contenido de la ventana de información:Java
// Use a custom info window adapter to handle multiple lines of text in the // info window contents. this.map.setInfoWindowAdapter( new GoogleMap.InfoWindowAdapter() { @Override // Return null here, so that getInfoContents() is called next. public View getInfoWindow(Marker arg0) { return null; } @Override public View getInfoContents(Marker marker) { // Inflate the layouts for the info window, title and snippet. View infoWindow = getLayoutInflater() .inflate( R.layout.custom_info_contents, (FrameLayout) findViewById(R.id.map), false); TextView title = infoWindow.findViewById(R.id.title); title.setText(marker.getTitle()); TextView snippet = infoWindow.findViewById(R.id.snippet); snippet.setText(marker.getSnippet()); return infoWindow; } });
Kotlin
// Use a custom info window adapter to handle multiple lines of text in the // info window contents. this.map?.setInfoWindowAdapter(object : InfoWindowAdapter { // Return null here, so that getInfoContents() is called next. override fun getInfoWindow(arg0: Marker): View? = null override fun getInfoContents(marker: Marker): View { // Inflate the layouts for the info window, title and snippet. val infoWindow = layoutInflater.inflate( R.layout.custom_info_contents, findViewById<FrameLayout>(R.id.map), false, ) val title = infoWindow.findViewById<TextView>(R.id.title) title.text = marker.title val snippet = infoWindow.findViewById<TextView>(R.id.snippet) snippet.text = marker.snippet return infoWindow } })
Guarda el estado del mapa
Guarda la posición de la cámara del mapa y la ubicación del dispositivo. Cuando un usuario rota un dispositivo Android o realiza cambios en la configuración, el framework de Android destruye y reconstruye la actividad en Maps. Para garantizar una experiencia del usuario sin inconvenientes, se recomienda almacenar el estado de la aplicación relevante y restablecerlo cuando sea necesario.
En este instructivo, se proporciona todo el código necesario para guardar el estado de un mapa. Si deseas obtener más detalles, consulta la guía sobre el paquete savedInstanceState.
En tu actividad en Maps, define valores de clave para almacenar el estado de la actividad:
Java
private static final String KEY_CAMERA_POSITION = "camera_position"; private static final String KEY_LOCATION = "location";
Kotlin
private const val KEY_CAMERA_POSITION = "camera_position" private const val KEY_LOCATION = "location"
Implementa la devolución de llamada
onSaveInstanceState()para guardar el estado cuando se detenga la actividad:Java
@Override protected void onSaveInstanceState(Bundle outState) { if (map != null) { outState.putParcelable(KEY_CAMERA_POSITION, map.getCameraPosition()); outState.putParcelable(KEY_LOCATION, lastKnownLocation); } super.onSaveInstanceState(outState); }
Kotlin
override fun onSaveInstanceState(outState: Bundle) { map?.let { map -> outState.putParcelable(KEY_CAMERA_POSITION, map.cameraPosition) outState.putParcelable(KEY_LOCATION, lastKnownLocation) } super.onSaveInstanceState(outState) }
En el método
onCreate()de tu actividad, recupera la ubicación del dispositivo y la posición de la cámara del mapa (si ya las guardaste):Java
// Retrieve location and camera position from saved instance state. if (savedInstanceState != null) { lastKnownLocation = savedInstanceState.getParcelable(KEY_LOCATION); cameraPosition = savedInstanceState.getParcelable(KEY_CAMERA_POSITION); }
Kotlin
if (savedInstanceState != null) { lastKnownLocation = savedInstanceState.getParcelable(KEY_LOCATION) cameraPosition = savedInstanceState.getParcelable(KEY_CAMERA_POSITION) }