如何获取谷歌地图的屏幕中心位置？
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【中文标题】如何获取谷歌地图的屏幕中心位置？【英文标题】：How to get screen center location of google map? 【发布时间】：2015-10-17 06:55:19 【问题描述】：我想创建一个带有静态标记的地图，以始终显示屏幕中心的位置。我在布局中创建了一个标记，中心是可绘制的图像。 现在我需要获取中心位置坐标并将它们转换为地址。之后在文本视图中显示所选位置作为我选择的位置。 需要帮助
【问题讨论】：
【参考方案1】：您可以随时通过在您的 GoogleMap 变量实例上调用此函数来获取地图的中心点
mMap.getCameraPosition().target
现在如果您想在每次更改地图时获取中心点，那么您需要实现OnCameraChangeListener 监听器并调用上面的行来获取新的中心点。
更新： OnCameraChangeListener 已替换为 OnCameraMoveStartedListener、OnCameraMoveListener 和 OnCameraIdleListener 听众。使用适合您用例的那个。
【讨论】：
你能提供一些例子吗？ 它工作得非常好，而且它的代码也比公认的答案更干净 @MANCHAI 如：double CameraLat = mMap.getCameraPosition().target.latitude; double CameraLong = mMap.getCameraPosition().target.longitude; 是的，这应该是公认的答案。如果一个人用 30 行代码给出了答案，而另一个人只用了一行代码给出了答案（没有明显的实现缺点），那么这一行应该始终是公认的答案。【参考方案2】：protected void userLocationMap()
mapFragment = ((SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map));
googleMap = mapFragment.getMap();
int status = GooglePlayServicesUtil
.isGooglePlayServicesAvailable(getBaseContext());
if (status != ConnectionResult.SUCCESS)
///if play services are not available
int requestCode = 10;
Dialog dialog = GooglePlayServicesUtil.getErrorDialog(status, this,
requestCode);
dialog.show();
else
// Enabling MyLocation Layer of Google Map
googleMap.setMyLocationEnabled(true);
// Creating a LatLng object for the current location
LatLng latLng = new LatLng(latitude, longitude);
// Showing the current location in Google Map
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
// Zoom in the Google Map
googleMap.animateCamera(CameraUpdateFactory.zoomTo(15));
Log.i("latitude", "==========" + latitude);
////locationTextView holds the address string
locationTextView.setText(getCompleteAdressString(latitude, longitude));
// create marker
MarkerOptions marker = new MarkerOptions().position(
new LatLng(latitude, longitude)).title("My Location");
// adding marker
googleMap.addMarker(marker);
getcompleteAdress 方法是:::::==>
private String getCompleteAddressString(double LATITUDE, double LONGITUDE)
String strAdd = "";
Geocoder geocoder = new Geocoder(this, Locale.getDefault());
try
List<Address> addresses = geocoder.getFromLocation(LATITUDE,
LONGITUDE, 1);
if (addresses != null)
Address returnedAddress = addresses.get(0);
StringBuilder strReturnedAddress = new StringBuilder("");
for (int i = 0; i < returnedAddress.getMaxAddressLineIndex(); i++)
strReturnedAddress
.append(returnedAddress.getAddressLine(i)).append(
",");
strAdd = strReturnedAddress.toString();
Log.w("My Current loction address",
"" + strReturnedAddress.toString());
else
Log.w("My Current loction address", "No Address returned!");
catch (Exception e)
e.printStackTrace();
Log.w("My Current loction address", "Canont get Address!");
return strAdd;
根据点击改变位置====>
googleMap.setOnMapClickListener(new OnMapClickListener()
@Override
public void onMapClick(LatLng point)
Log.d("Map","Map clicked");
marker.remove();
double latitude = latLng.latitude;
double longitude = latLng.longitude;
locationTextView.setText(getCompleteAdressString(latitude,longitude ));
drawMarker(point);
);
【讨论】：
如果您对我们的回答不满意，请告诉我们 我已编辑我的答案以将您的问题包含在 cmets 中。但问题不是很清楚。如果您不满意，请告诉我们【参考方案3】：这将提供中心屏幕的纬度和纬度
LatLng centerLatLang =
mMap.getProjection().getVisibleRegion().latLngBounds.getCenter();
【讨论】：
【参考方案4】：我已经成功地为我当前的位置创建了地图。但它只提供一次我的位置坐标，我需要在移动到其他位置时获取位置。发布我的代码
import java.io.IOException;
import java.util.List;
import java.util.Locale;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesUtil;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.GoogleMap.OnCameraChangeListener;
import com.google.android.gms.maps.GoogleMap.OnMapClickListener;
import com.google.android.gms.maps.GoogleMap.OnMapLongClickListener;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.CameraPosition;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.maps.GeoPoint;
import android.app.ActionBar;
import android.app.Activity;
import android.app.Dialog;
import android.graphics.Canvas;
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.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.util.Log;
import android.view.Menu;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
public class MapLocation extends FragmentActivity implements LocationListener
GoogleMap googleMap;
MarkerOptions markerOptions;
LatLng latLng;
ImageView icon;
TextView selected;
@Override
protected void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_map);
icon = (ImageView)findViewById(R.id.icon_baby);
icon.setOnClickListener(new OnClickListener()
@Override
public void onClick(View v)
// TODO Auto-generated method stub
finish();
);
// Getting Google Play availability status
int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(getBaseContext());
// Showing status
if(status!=ConnectionResult.SUCCESS) // Google Play Services are not available
int requestCode = 10;
Dialog dialog = GooglePlayServicesUtil.getErrorDialog(status, this, requestCode);
dialog.show();
else // Google Play Services are available
// Getting reference to the SupportMapFragment of activity_main.xml
SupportMapFragment fm = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
// Getting GoogleMap object from the fragment
googleMap = fm.getMap();
// Enabling MyLocation Layer of Google Map
googleMap.setMyLocationEnabled(true);
// Getting LocationManager object from System Service LOCATION_SERVICE
LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
// Creating a criteria object to retrieve provider
Criteria criteria = new Criteria();
// Getting the name of the best provider
String provider = locationManager.getBestProvider(criteria, true);
// Getting Current Location
Location location = locationManager.getLastKnownLocation(provider);
if(location!=null)
onLocationChanged(location);
locationManager.requestLocationUpdates(provider, 20000, 0, this);
//@Override
public void onLocationChanged(Location location)
TextView tvLocation = (TextView) findViewById(R.id.selected_location);
// Getting latitude of the current location
double latitude = location.getLatitude();
// Getting longitude of the current location
double longitude = location.getLongitude();
// Creating a LatLng object for the current location
LatLng latLng = new LatLng(latitude, longitude);
// Showing the current location in Google Map
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
// Zoom in the Google Map
googleMap.animateCamera(CameraUpdateFactory.zoomTo(15));
// Setting latitude and longitude in the TextView tv_location
tvLocation.setText("Latitude:" + latitude + ", Longitude:"+ longitude );
@Override
public void onStatusChanged(String provider, int status, Bundle extras)
// TODO Auto-generated method stub
@Override
public void onProviderEnabled(String provider)
// TODO Auto-generated method stub
@Override
public void onProviderDisabled(String provider)
// TODO Auto-generated method stub
【讨论】：
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