android - 谷歌地图 API 位置更新

Question

我在我的 android 应用程序中使用 map ，但我想使用位置更新并将其显示在 map 上，我正在关注谷歌开发人员关于使用 LocationRequest() 进行位置更新的文档，但不知道如何使用这进入 map 。这是我的 activity.java

import android.content.Context;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationManager;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.util.Log;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.location.LocationRequest;
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.MapFragment;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.GoogleApiClient.ConnectionCallbacks;
import com.google.android.gms.common.api.GoogleApiClient.OnConnectionFailedListener;

public class MapaActivity extends FragmentActivity implements OnMapReadyCallback,ConnectionCallbacks,OnConnectionFailedListener, LocationListener {

    private GoogleMap mMap; // Might be null if Google Play services APK is not available.

    private GoogleApiClient mGoogleApiClient;
    // Request code to use when launching the resolution activity
    private static final int REQUEST_RESOLVE_ERROR = 1001;
    // Unique tag for the error dialog fragment
    private static final String DIALOG_ERROR = "dialog_error";
    // Bool to track whether the app is already resolving an error
    private boolean mResolvingError = false;
    // etiqueta para logs
    private final String TAG="Mapas";
    //coordenadas-------------------
    private String lat;
    private String lon;
    //variables para localizacion
    Location mLastLocation;
    Location mCurrentLocation;
    LocationRequest mLocationRequest;
    String mLastUpdateTime;
    //// posicion anterior///////////////
    LocationManager locationManager;



    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_mapa);
        // Create a GoogleApiClient instance
        // Kick off the process of building a GoogleApiClient and requesting the LocationServices
        // API.
        buildGoogleApiClient();
//nuevo codigo
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);


    }

    protected synchronized void buildGoogleApiClient() {
        Log.v(TAG, "Lanzando GoogleApiClient");
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
        createLocationRequest();
    }
    //location request
    // actualiza cada 40 segundos min 20 segundos
    protected void createLocationRequest() {
        mLocationRequest = new LocationRequest();
        mLocationRequest.setInterval(40000);
        mLocationRequest.setFastestInterval(20000);
        //prioridad alta precision
        mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
        // Log.v(TAG,"se ingresa al locationRequest");
    }

    @Override
    protected void onResume() {
        super.onResume();
        //    setUpMapIfNeeded();
    }
    @Override
    protected void  onPause(){
        super.onPause();
        Log.v(TAG, "evento onPause");
    }

    @Override
    protected void onStop(){
        super.onStop();
        Log.v(TAG, "evento onStop");

    }
    @Override
    protected void onDestroy(){
        super.onDestroy();
        Log.v(TAG, "evento onDestroy");
    };
    @Override
    public void onMapReady(GoogleMap googleMap) {
        // Add a marker in Sydney, Australia, and move the camera.

        // habilitar controles de zoom
        googleMap.getUiSettings().setZoomControlsEnabled(true);
        googleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
        //habilitar brujula
        googleMap.getUiSettings().setCompassEnabled(true);
        googleMap.setMyLocationEnabled(true);

        // para pasar a funcion
        locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
        // Create a criteria object needed to retrieve the provider
        Criteria criteria = new Criteria();
        // Get the name of the best available provider
        String provider = locationManager.getBestProvider(criteria, true);

        // We can use the provider immediately to get the last known location
        Location location = locationManager.getLastKnownLocation(provider);
        googleMap.clear();
        //  convert the location object to a LatLng object that can be used by the map API
        LatLng currentPosition = new LatLng(location.getLatitude(), location.getLongitude());
        Log.v(TAG, "Latitud :" + location.getLatitude());
        googleMap.addMarker(new MarkerOptions().position(currentPosition).title("Yo"));
        // zoom to the current location
        googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(currentPosition, 13));
        googleMap.setMyLocationEnabled(true);
        Log.v(TAG, currentPosition.toString());
        //pasar la posicion para grabar en el servidor

    }

    @Override
    public void onConnected(Bundle bundle) {
    }
    @Override
    public void onConnectionSuspended(int i) {
    }
    @Override
    public void onLocationChanged(Location location) {
    }
    @Override
    public void onConnectionFailed(ConnectionResult connectionResult) {

    }
}

这是我的观点

<fragment xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/map"
    tools:context=".MapaActivity"
    android:name="com.google.android.gms.maps.SupportMapFragment" />

Answer 1

看起来您正在将 FusedLocationProviderApi 与旧的开源 Location API 混合使用。如果您使用的是 FusedLocationProviderApi，请坚持使用。

您遗漏了两个关键部分，对 mGoogleApiClient.connect() 的调用，以及对 requestLocationUpdates() 的调用。

这是您的代码的一般结构:

public class MainActivity extends FragmentActivity
        implements OnMapReadyCallback,
        GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener,
        LocationListener {

    private GoogleMap map;
    private LocationRequest mLocationRequest;
    private GoogleApiClient mGoogleApiClient;
    private Location mLastLocation;
    private Marker marker;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    @Override
    protected void onResume() {
        super.onResume();

        buildGoogleApiClient();
        mGoogleApiClient.connect();

        if (map == null) {
            SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                    .findFragmentById(R.id.map);

            mapFragment.getMapAsync(this);
        }
    }

    @Override
    public void onMapReady(GoogleMap retMap) {

        map = retMap;

        setUpMap();

    }

    public void setUpMap(){

        map.setMapType(GoogleMap.MAP_TYPE_HYBRID);
        map.setMyLocationEnabled(true);
    }

    @Override
    protected void onPause(){
        super.onPause();
        if (mGoogleApiClient != null) {
            LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);
        }
    }

    protected synchronized void buildGoogleApiClient() {
        Toast.makeText(this, "buildGoogleApiClient", Toast.LENGTH_SHORT).show();
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
    }

    @Override
    public void onConnected(Bundle bundle) {
        Toast.makeText(this,"onConnected",Toast.LENGTH_SHORT).show();

        mLocationRequest = new LocationRequest();
        mLocationRequest.setInterval(1000);
        mLocationRequest.setFastestInterval(1000);
        mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);

        //mLocationRequest.setSmallestDisplacement(0.1F);

        LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);
    }

    @Override
    public void onConnectionSuspended(int i) {
        Toast.makeText(this,"onConnectionSuspended",Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onConnectionFailed(ConnectionResult connectionResult) {
        Toast.makeText(this,"onConnectionFailed",Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onLocationChanged(Location location) {
        mLastLocation = location;

        //remove previous current location Marker
        if (marker != null){
            marker.remove();
        }

        double dLatitude = mLastLocation.getLatitude();
        double dLongitude = mLastLocation.getLongitude();
        marker = map.addMarker(new MarkerOptions().position(new LatLng(dLatitude, dLongitude))
                .title("My Location").icon(BitmapDescriptorFactory
                        .defaultMarker(BitmapDescriptorFactory.HUE_RED)));
        map.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(dLatitude, dLongitude), 8));

    }

}