Android Studio Google Map 应用程序不再显示地图

Question

我一直在为一个项目开发一个小型应用程序，该应用程序旨在显示用户的位置并在他们四处移动时跟踪他们，同时让他们显示标记。直到今天我启动应用程序并发现它不再显示地图之前，这一切都很好。 Google 徽标与缩放选项一起显示在页面底部，但地图本身永远不会加载。这是我的地图活动的代码。

import androidx.annotation.NonNull;
import androidx.core.app.ActivityCompat;
import androidx.fragment.app.FragmentActivity;

import android.Manifest;
import android.content.Context;
import android.content.pm.PackageManager;
import android.location.Address;
import android.location.Criteria;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;

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.UiSettings;
import com.google.android.gms.maps.model.BitmapDescriptor;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MapStyleOptions;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.maps.GoogleMap.OnMarkerClickListener;
import com.google.firebase.firestore.FirebaseFirestore;

import java.io.IOException;
import java.util.List;

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback{

  private GoogleMap mMap;
  LocationManager locationManager;
  private static final int REQUEST_LOCATION_PERMISSION = 1;
  Marker mMarker;
  LocationListener locationListener;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_maps);
      // 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);
      locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
      if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED)
      {
          ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_LOCATION_PERMISSION);
      }
      locationListener = new LocationListener() {
          @Override
          public void onLocationChanged(Location location) {
              double latitude = location.getLatitude();
              double longitude = location.getLongitude();
              //get the location name from latitude and longitude
              Geocoder geocoder = new Geocoder(getApplicationContext());
              try {
                  List<Address> addresses =
                          geocoder.getFromLocation(latitude, longitude, 1);
                  String result = addresses.get(0).getLocality()+":";
                  result += addresses.get(0).getCountryName();
                  LatLng latLng = new LatLng(latitude, longitude);

                  if (mMarker != null){
                      mMarker.remove();
                      mMarker = mMap.addMarker(new MarkerOptions().position(latLng).title(result));
                      mMap.setMaxZoomPreference(21);

                  }
                  else {

                      mMarker = mMap.addMarker(new MarkerOptions().position(latLng).title(result));
                      mMap.setMaxZoomPreference(21);
                      mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng, 20.0f));

                  }

              } catch (IOException e) {
                  e.printStackTrace();
              }
          }

          @Override
          public void onStatusChanged(String provider, int status, Bundle extras) {

          }

          @Override
          public void onProviderEnabled(String provider) {

          }

          @Override
          public void onProviderDisabled(String provider) {

          }
      };
      locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 400, 0, locationListener);
      locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 400, 0, locationListener);
  }




  @Override
  public void onMapReady(GoogleMap googleMap){
      mMap = googleMap;
      mMap.setMapStyle(MapStyleOptions.loadRawResourceStyle(this, R.raw.style_json));
      //Setting Map zoom controls to be enabled
      mMap.getUiSettings().setZoomControlsEnabled(true);
      mMap.getUiSettings().setZoomGesturesEnabled(true);
      mMap.setOnMapLongClickListener(new GoogleMap.OnMapLongClickListener(){
          public void onMapLongClick(LatLng latLng){
              //creating marker
              MarkerOptions markerOptions = new MarkerOptions();
              //set marker position
              markerOptions.position(latLng);
              //set latitude and longitude on marker
              markerOptions.title(latLng.latitude+ " : " + latLng.longitude);
              //clear the previous click position
              mMap.clear();
              //add marker on map
              mMap.addMarker(markerOptions);
          }
      });

  }

  @Override
  protected void onStop() {
      super.onStop();
      locationManager.removeUpdates(locationListener);
  }
}

这是我在运行地图活动后重复出现的错误消息

W/System.err: java.io.IOException: grpc failed
W/System.err:     at android.location.Geocoder.getFromLocation(Geocoder.java:136)
        at com.example.pubapp.MapsActivity$1.onLocationChanged(MapsActivity.java:65)
        at android.location.LocationManager$ListenerTransport._handleMessage(LocationManager.java:371)
        at android.location.LocationManager$ListenerTransport.access$000(LocationManager.java:300)
        at android.location.LocationManager$ListenerTransport$1.handleMessage(LocationManager.java:316)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:193)
        at android.app.ActivityThread.main(ActivityThread.java:6669)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

就像我昨晚说的，这个应用程序运行得非常好，从那以后我没有真正改变任何东西，只是添加了几个当前未使用的活动。我已经尝试更改 API 密钥，使用新的模拟器并在 android studio 上进行全新安装，但到目前为止没有任何效果。

Answer 1

今天打开项目，发现重启电脑解决了问题，不再出现错误，地图显示正常。