这是我的 AddressForCart 地图活动
public class AddressForCart extends FragmentActivity implements OnMapReadyCallback {
private GoogleMap mMap;
LocationManager locationManager;
@SuppressLint("MissingPermission") //I have already asked for permission before opening this activity via intent. Dont worry about this
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_address_for_cart);
// 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 (locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER)) {
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, new LocationListener() {
@Override
public void onLocationChanged(Location location) {
double latitude = location.getLatitude();
double longitude = location.getLongitude();
LatLng latLng = new LatLng(latitude,longitude);
displayOnMap(latLng,13.2f);
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
});
} else if(locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)){
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, new LocationListener() {
@Override
public void onLocationChanged(Location location) {
double latitude = location.getLatitude();
double longitude = location.getLongitude();
LatLng latLng = new LatLng(latitude,longitude);
displayOnMap(latLng,13.2f);
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onProviderDisabled(String provider) {
}
});
}
}
@Override
public void onMapReady(final GoogleMap googleMap) {
mMap = googleMap;
mMap.setOnMapClickListener(new GoogleMap.OnMapClickListener() {
@Override
public void onMapClick(LatLng latLng) {
displayOnMap(latLng,0f);
}
});
}
public void displayOnMap(LatLng latLng, Float zoom){
Geocoder geocoder = new Geocoder(getApplicationContext());
try {
mMap.clear();
List<Address> addressList = geocoder.getFromLocation(latLng.latitude,latLng.longitude,1);
String str = addressList.get(0).getAddressLine(0) + ", ";
str += addressList.get(0).getCountryName();
mMap.addMarker(new MarkerOptions().position(latLng).title(str));
if(zoom!=0)
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(latLng, zoom));
else
mMap.animateCamera(CameraUpdateFactory.newLatLng(latLng));
} catch (IOException e) {
e.printStackTrace();
}
}
}
问题：假设打开地图时，它指向位置“ A”。现在，我想拖动标记图钉并通过单击地图上的不同位置（例如“ B”，“ C”，“ D”等）在地图上移动。发生的事情是，图钉正确地移动到了新位置地图，但有时在地图上标记不同的位置时，它会刷新并返回到初始位置。 也就是说，当我从A转到B到C时，有时，当我从B转到C时，该引脚会自动返回A，就好像它已经刷新一样。
编辑1：我注意到onCreate（）中的onLocationChanged被调用，然后又返回。为什么会这样？