要在Android应用中显示用户的位置,可以使用Google Maps API和Location API。以下是一个包含代码示例的解决方法:
implementation 'com.google.android.gms:play-services-maps:17.0.1'
implementation 'com.google.android.gms:play-services-location:18.0.0'
import android.Manifest;
import android.content.pm.PackageManager;
import android.location.Location;
import android.os.Bundle;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import com.google.android.gms.location.FusedLocationProviderClient;
import com.google.android.gms.location.LocationCallback;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationResult;
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.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
public class MapsActivity extends AppCompatActivity implements OnMapReadyCallback {
private static final int LOCATION_PERMISSION_REQUEST_CODE = 1;
private GoogleMap googleMap;
private FusedLocationProviderClient fusedLocationProviderClient;
private LocationCallback locationCallback;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.mapView);
mapFragment.getMapAsync(this);
fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this);
locationCallback = new LocationCallback() {
@Override
public void onLocationResult(LocationResult locationResult) {
if (locationResult == null) {
return;
}
for (Location location : locationResult.getLocations()) {
LatLng latLng = new LatLng(location.getLatitude(), location.getLongitude());
googleMap.addMarker(new MarkerOptions().position(latLng));
googleMap.animateCamera(CameraUpdateFactory.newLatLngZoom(latLng, 15));
}
}
};
}
@Override
public void onMapReady(GoogleMap googleMap) {
this.googleMap = googleMap;
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
!= PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION},
LOCATION_PERMISSION_REQUEST_CODE);
} else {
startLocationUpdates();
}
}
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if (requestCode == LOCATION_PERMISSION_REQUEST_CODE) {
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
startLocationUpdates();
}
}
}
@Override
protected void onResume() {
super.onResume();
startLocationUpdates();
}
@Override
protected void onPause() {
super.onPause();
stopLocationUpdates();
}
private void startLocationUpdates() {
LocationRequest locationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(5000)
.setFastestInterval(1000);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
fusedLocationProviderClient.requestLocationUpdates(locationRequest, locationCallback, null);
}
}
private void stopLocationUpdates() {
fusedLocationProviderClient.removeLocationUpdates(locationCallback);
}
}
这个示例代码使用了SupportMapFragment
来显示地图,并通过FusedLocationProviderClient
获取用户的位置更新。当用户位置更新时,将在地图上添加一个标记,并将地图的视图中心移动到用户的位置。
请注意,在运行代码之前,您需要在Google开发者控制台上创建一个项目,并为该项目启用Google Maps API和将其与应用关联的API密钥。