问题
I have been googling this for hours but no luck so far.
I want to get the address of the location where the map is touched / tapped.
I understand that in order to get the address i need to reverse geocode the coordinates. But how do i get the coordinates from the map in the first place?
回答1:
All you need to do is set up a OnMapClickListener, and then the onMapClick()
override will give you a LatLng
object. Then, use a Geocoder object to get the address of the point that was just clicked on.
In this simple example, I've also added a Marker every time the user clicks a new point on the map.
Here is the main piece of functionality that you need:
mMap.setOnMapClickListener(new GoogleMap.OnMapClickListener() {
@Override
public void onMapClick(LatLng point) {
//save current location
latLng = point;
List<Address> addresses = new ArrayList<>();
try {
addresses = geocoder.getFromLocation(point.latitude, point.longitude,1);
} catch (IOException e) {
e.printStackTrace();
}
android.location.Address address = addresses.get(0);
if (address != null) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < address.getMaxAddressLineIndex(); i++){
sb.append(address.getAddressLine(i) + "\n");
}
Toast.makeText(MapsActivity.this, sb.toString(), Toast.LENGTH_LONG).show();
}
//remove previously placed Marker
if (marker != null) {
marker.remove();
}
//place marker where user just clicked
marker = mMap.addMarker(new MarkerOptions().position(point).title("Marker")
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA)));
}
});
Here is the full class that I used to test this:
public class MapsActivity extends AppCompatActivity {
private GoogleMap mMap;
private LatLng latLng;
private Marker marker;
Geocoder geocoder;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
geocoder = new Geocoder(this, Locale.getDefault());
setUpMapIfNeeded();
}
@Override
protected void onResume() {
super.onResume();
setUpMapIfNeeded();
}
private void setUpMapIfNeeded() {
// Do a null check to confirm that we have not already instantiated the map.
if (mMap == null) {
// Try to obtain the map from the SupportMapFragment.
mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map))
.getMap();
// Check if we were successful in obtaining the map.
if (mMap != null) {
setUpMap();
}
}
}
private void setUpMap() {
mMap.setMyLocationEnabled(true);
mMap.setMapType(GoogleMap.MAP_TYPE_HYBRID);
mMap.getUiSettings().setMapToolbarEnabled(false);
mMap.setOnMapClickListener(new GoogleMap.OnMapClickListener() {
@Override
public void onMapClick(LatLng point) {
//save current location
latLng = point;
List<Address> addresses = new ArrayList<>();
try {
addresses = geocoder.getFromLocation(point.latitude, point.longitude,1);
} catch (IOException e) {
e.printStackTrace();
}
android.location.Address address = addresses.get(0);
if (address != null) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < address.getMaxAddressLineIndex(); i++){
sb.append(address.getAddressLine(i) + "\n");
}
Toast.makeText(MapsActivity.this, sb.toString(), Toast.LENGTH_LONG).show();
}
//remove previously placed Marker
if (marker != null) {
marker.remove();
}
//place marker where user just clicked
marker = mMap.addMarker(new MarkerOptions().position(point).title("Marker")
.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA)));
}
});
}
}
Result of tapping the map in two different points:
回答2:
Google Map has callbacks to do that like this one or this one.
Just implement them in your code and as soon as they're fired, just make a reverse geocode the coordinates. You actually found the most complicated part (you understood that you need to reverse geocode).
来源:https://stackoverflow.com/questions/31248257/androidgoogle-maps-get-the-address-of-location-on-touch