我正在开发一个应用程序,它应该在 Android 上显示设备的当前位置。google maps
问题是我没有得到设备的确切或附近位置。
我有课:
public class GPSLocatorActivity extends MapActivity {
private MapView mapView;
private MapController mapController;
private LocationManager locationManager;
private LocationListener locationListener;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationListener = new GPSLocationListener();
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
0,
0,
locationListener);
mapView = (MapView) findViewById(R.id.mapView);
// enable Street view by default
// mapView.setStreetView(true);
// enable to show Satellite view
mapView.setSatellite(true);
// enable to show Traffic on map
mapView.setTraffic(true);
mapView.setBuiltInZoomControls(true);
// myLocationOverlay=new MyLocationOverlay(this,mapView);
mapController = mapView.getController();
mapController.setZoom(16);
}
@Override
protected boolean isRouteDisplayed() {
return false;
}
private class GPSLocationListener implements LocationListener
{
@Override
public void onLocationChanged(Location location) {
if (location != null) {
GeoPoint point = new GeoPoint(
(int) (location.getLatitude() * 1E6),
(int) (location.getLongitude() * 1E6));
/* Toast.makeText(getBaseContext(),
"Latitude: " + location.getLatitude() +
" Longitude: " + location.getLongitude(),
Toast.LENGTH_SHORT).show();*/
mapController.animateTo(point);
mapController.setZoom(16);
// add marker
MapOverlay mapOverlay = new MapOverlay();
mapOverlay.setPointToDraw(point);
List<Overlay> listOfOverlays = mapView.getOverlays();
listOfOverlays.clear();
listOfOverlays.add(mapOverlay);
String address = ConvertPointToLocation(point);
Toast.makeText(getBaseContext(), address, Toast.LENGTH_SHORT).show();
mapView.invalidate();
}
}
public String ConvertPointToLocation(GeoPoint point) {
String address = "";
Geocoder geoCoder = new Geocoder(
getBaseContext(), Locale.getDefault());
try {
List<Address> addresses = geoCoder.getFromLocation(
point.getLatitudeE6() / 1E6,
point.getLongitudeE6() / 1E6, 1);
if (addresses.size() > 0) {
for (int index = 0; index < addresses.get(0).getMaxAddressLineIndex(); index++)
address += addresses.get(0).getAddressLine(index) + " ";
}
}
catch (IOException e) {
e.printStackTrace();
}
return address;
}
@Override
public void onProviderDisabled(String provider) {
}
@Override
public void onProviderEnabled(String provider) {
}
@Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
}
class MapOverlay extends Overlay
{
private GeoPoint pointToDraw;
public void setPointToDraw(GeoPoint point) {
pointToDraw = point;
}
public GeoPoint getPointToDraw() {
return pointToDraw;
}
@Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow, long when) {
super.draw(canvas, mapView, shadow);
// convert point to pixels
Point screenPts = new Point();
mapView.getProjection().toPixels(pointToDraw, screenPts);
// add marker
Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.red);
canvas.drawBitmap(bmp, screenPts.x, screenPts.y - 24, null); // 24 is the height of image
return true;
}
}
}
我在 Mainfest 文件中添加了权限:
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />
我添加了权限,并为地图使用了精确的 Google Api 密钥。