Question

我正在尝试使用google map活动向用户显示当前位置。当活动启动时，谷歌地图按原样显示，但没有标记，也没有获得用户的当前位置。该地图显示了许多不同国家/地区的视图。在将Toast消息放入每种方法之后，我意识到没有调用onLocationChange，因为此方法没有Toast出现。

import android.Manifest;
import android.content.Context;
import android.content.pm.PackageManager;
import android.location.Location;
import android.os.Build;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.support.v4.content.ContextCompat;
import android.widget.Toast;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.common.api.GoogleApiClient;
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.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;

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

    private GoogleMap mMap;
    private GoogleApiClient googleApiClient;
    private LocationRequest locationRequest;
    private Location lastKnownLocation;
    private Marker userLocationMarker;

    private static final int REQUEST_USER_LOCATION_CODE = 99;

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

        if(Build.VERSION.SDK_INT > Build.VERSION_CODES.M)
        {
            checkPermissions();
        }

        // Obtain the SupportMapFragment and get notified when the map is ready to be used.
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);
    }

    @Override
    public void onMapReady(GoogleMap googleMap)
    {
        // Get the users current location
        mMap = googleMap;

        // Check that the access permissions are granted by the device
        if(ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED)
        {
            buildGoogleApiClient();
            mMap.setMyLocationEnabled(true);

        }
    }

    protected synchronized void buildGoogleApiClient()
    {
        googleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();

        googleApiClient.connect();
    }

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

        if(userLocationMarker != null)
        {
            // Remove that marker as if marker already exists it is likely wrong
            userLocationMarker.remove();
        }

        // Get users longitude and latitude
        LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());

        // Display Marker on users current location
        MarkerOptions markerOptions = new MarkerOptions();
        markerOptions.position(latLng);
        markerOptions.title("You are Here");
        markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_VIOLET));

        userLocationMarker = mMap.addMarker(markerOptions);

        //Focus map on users current location
        mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
        mMap.animateCamera(CameraUpdateFactory.zoomBy(1));

        if(googleApiClient != null)
        {
            LocationServices.FusedLocationApi.removeLocationUpdates(googleApiClient, this);
        }
    }

    @Override
    public void onConnected(@Nullable Bundle bundle)
    {
        // Update map while user is currently moving
        locationRequest= new LocationRequest();
        locationRequest.setInterval(1100);
        locationRequest.setFastestInterval(1100);
        locationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);

        if(ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED)
        {
            LocationServices.FusedLocationApi.requestLocationUpdates(googleApiClient, locationRequest, this);
        }

    }

    @Override
    public void onConnectionSuspended(int i)
    {

    }

    @Override
    public void onConnectionFailed(@NonNull ConnectionResult connectionResult)
    {

    }

    private boolean checkPermissions()
    {
        if(ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED)
        {
            if(ActivityCompat.shouldShowRequestPermissionRationale(this,Manifest.permission.ACCESS_FINE_LOCATION))
            {
                ActivityCompat.requestPermissions(this, new String[] {Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_USER_LOCATION_CODE);
            }
            else
            {
                ActivityCompat.requestPermissions(this, new String[] {Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_USER_LOCATION_CODE);
            }
            return false;
        }
        else
        {
            return true;
        }

    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults)
    {
        switch(requestCode)
        {
            case REQUEST_USER_LOCATION_CODE:
                if(grantResults.length > 0 && grantResults[0]== PackageManager.PERMISSION_GRANTED)
                {
                    if(ContextCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED)
                    {
                        if(googleApiClient == null)
                        {
                            buildGoogleApiClient();
                        }
                        mMap.setMyLocationEnabled(true);
                    }
                }
                else
                {
                    Toast.makeText(this, "Permission Denied", Toast.LENGTH_LONG).show();
                }
        }

    }
}

权限

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />

Answer 1

要显示用户位置，您应该添加：

mMap.setMyLocationEnabled(true);

在onMapReady回调中，无需使用LocationRequest。请注意，您的应用获得位置权限后就可以获取用户位置。为此，您可以遵循此guide或使用第三方库，例如easy permissions

Answer 2

经过数小时的研究，答案就摆在我眼前，手机设置中的位置设置已被禁用。弄清楚了，所以下一个人像我一样愚蠢。

Android Maps SDK无法获取当前位置

2 个答案: