How to get center points when i view map in google maps v2 in android?

Question

Hi, I make the application very much in my application, there is a map, so I implemented Google Maps V2, and I have a problem. When I look at the map, I want to get the center points of the map, if I scroll the map and I leave it, then it will get the center points of the map, so anyone can suggest to solve this problem, it may be useful. Thanks in advance.

Note I used Google Maps V2, so please write about it.

public class Mapview extends FragmentActivity implements OnMapClickListener, OnCameraChangeListener{ final int RQS_GooglePlayServices = 1; private GoogleMap myMap; Location myLocation; TextView tvLocInfo; GPSTracker gps; public double Latitude,Longitude; String Datetime, addr,RegUID; public String lat,longd; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.mapview); tvLocInfo = (TextView)findViewById(R.id.locinfo); FragmentManager myFragmentManager = getSupportFragmentManager(); SupportMapFragment mySupportMapFragment = (SupportMapFragment)myFragmentManager.findFragmentById(R.id.map); myMap = mySupportMapFragment.getMap(); myMap.setMapType(GoogleMap.MAP_TYPE_NORMAL); myMap.setMyLocationEnabled(true); myMap.setOnMapClickListener(this); Projection P = myMap.getProjection(); Log.e("lat", String.valueOf(Latitude)); Log.e("lat", String.valueOf(Longitude)); Button mDone = (Button) findViewById(R.id.button1); mDone.setOnClickListener(new View.OnClickListener() { @SuppressLint("SimpleDateFormat") public void onClick(View v) { //Toast.makeText(getBaseContext(), "latitude"+lat+""+"longitude"+longd , Toast.LENGTH_LONG).show(); String timeStamp = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(Calendar.getInstance().getTime()); Datetime = timeStamp.toString(); Log.e("t", Datetime); RegUID = Utils.RegisterUserId; Log.e("t", RegUID); final ProgressDialog dialog = ProgressDialog.show(Mapview.this, "", Utils.Loading, true); dialog.show(); Handler handler = new Handler(); handler.postDelayed(new Runnable(){ @SuppressWarnings("unused") public void run() { try { String EMPLOYEE_SERVICE_URI = Utils.Request+"UserID="+RegUID+"&Location="+URLEncoder.encode(addr,"UTF-8")+"&Latitude="+lat+"&Longitude="+longd+"&RequestDate="+URLEncoder.encode(Datetime,"UTF-8"); Log.e(EMPLOYEE_SERVICE_URI, EMPLOYEE_SERVICE_URI); JSONObject JObject = Utils.getResult(EMPLOYEE_SERVICE_URI); //Toast.makeText(Mapview.this,JObject.toString(), Toast.LENGTH_LONG).show(); if(JObject!=null) { if(JObject.getBoolean("Valid")) { AlertDialog alertDialog = new AlertDialog.Builder(Mapview.this).create(); Utils.callAlert(JObject.getString("Message"), alertDialog); } else { AlertDialog alertDialog = new AlertDialog.Builder(Mapview.this).create(); Utils.callAlert(JObject.getString("Message"), alertDialog); } } else { AlertDialog alertDialog = new AlertDialog.Builder(Mapview.this).create(); Utils.callAlert(JObject.getString("Message"), alertDialog); } } catch (Exception e) { //Toast.makeText(Mapview.this,e.toString(), Toast.LENGTH_LONG).show(); Log.e("Exception", e.toString()); } dialog.dismiss(); }//run() ends }, 5000); } }); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; } @Override protected void onResume() { // TODO Auto-generated method stub super.onResume(); int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(getApplicationContext()); if (resultCode == ConnectionResult.SUCCESS){ Toast.makeText(getApplicationContext(), "isGooglePlayServicesAvailable SUCCESS", Toast.LENGTH_LONG).show(); }else{ GooglePlayServicesUtil.getErrorDialog(resultCode, this, RQS_GooglePlayServices); } } public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { Log.i("test","onScroll"); return false; } @Override public void onMapClick(LatLng point) { Log.e("lat", String.valueOf(point.latitude)); Log.e("lat", String.valueOf(point.longitude)); Latitude =point.latitude; Longitude = point.longitude; lat = String.valueOf(point.latitude); longd = String.valueOf(point.longitude); myMap.moveCamera(CameraUpdateFactory.newLatLng(point)); gps = new GPSTracker(Mapview.this); // check if GPS enabled if(gps.canGetLocation()) { Geocoder geoCoder = new Geocoder(getBaseContext(), 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("\n"); } addr = new String(strReturnedAddress); tvLocInfo.setText(addr.toString()); //Toast.makeText(getApplicationContext(), addr.toString(),Toast.LENGTH_LONG).show(); } else { Toast.makeText(getApplicationContext(), "Gps location address is unavailable please try again later", Toast.LENGTH_LONG).show(); } } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } @Override public void onCameraChange(CameraPosition arg0) { // TODO Auto-generated method stub } } 

Answer 1

You can use: -

 myMap.setOnCameraChangedListener(this); 

And in the listener: -

 onCameraChange(CameraPosition position) { LatLng target = position.target; // do what you need with the position here } 

I am not sure about the index outside. But to set the default position of the card, you can use something like: -

  private void setDefaultMapPosition(LatLng latLng) { CameraPosition camPos = new CameraPosition.Builder().target(latLng) .zoom(A_DEFAULT_MAP_ZOOM) .bearing(0) .tilt(0) .build(); myMap.moveCamera( CameraUpdateFactory.newCameraPosition(camPos)); } 

Answer 2

The OnCameraChangeListener interface OnCameraChangeListener deprecated. Now you can use OnCameraIdleListener now

Called when the camera’s movement is finished, there are no pending animations and the user has stopped interacting with the map.

and get the coordinates of the center by doing:

 val centerCoordinates = mMap.cameraPosition.target