【发布时间】:2014-05-29 09:42:36
【问题描述】:
我尝试了一些代码来进行地理编码反向定位(使用 Google Maps Android API v2)并显示带有标记的标题,但是当我运行我的应用程序时没有显示标记标题。 这是我的代码:
public class MainActivity extends FragmentActivity {
GoogleMap googleMap;
MarkerOptions markerOptions;
LatLng latLng;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
SupportMapFragment supportMapFragment = (SupportMapFragment)
getSupportFragmentManager().findFragmentById(R.id.map);
// Getting a reference to the map
googleMap = supportMapFragment.getMap();
// Setting a click event handler for the map
googleMap.setOnMapClickListener(new OnMapClickListener() {
@Override
public void onMapClick(LatLng arg0) {
// Getting the Latitude and Longitude of the touched location
latLng = arg0;
// Clears the previously touched position
googleMap.clear();
// Animating to the touched position
googleMap.animateCamera(CameraUpdateFactory.newLatLng(latLng));
// Creating a marker
markerOptions = new MarkerOptions();
// Setting the position for the marker
markerOptions.position(latLng);
// Placing a marker on the touched position
googleMap.addMarker(markerOptions);
// Adding Marker on the touched location with address
new ReverseGeocodingTask(getBaseContext()).execute(latLng);
}
});
}
private class ReverseGeocodingTask extends AsyncTask<LatLng, Void, String>{
Context mContext;
public ReverseGeocodingTask(Context context){
super();
mContext = context;
}
// Finding address using reverse geocoding
@Override
protected String doInBackground(LatLng... params) {
Geocoder geocoder = new Geocoder(mContext);
double latitude = params[0].latitude;
double longitude = params[0].longitude;
List<Address> addresses = null;
String addressText="";
try {
addresses = geocoder.getFromLocation(latitude, longitude,1);
} catch (IOException e) {
e.printStackTrace();
}
if(addresses != null && addresses.size() > 0 ){
Address address = addresses.get(0);
addressText = String.format("%s, %s, %s",
address.getMaxAddressLineIndex() > 0 ? address.getAddressLine(0) : "",
address.getLocality(),
address.getCountryName());
}
return addressText;
}
@Override
protected void onPostExecute(String addressText) {
// Setting the title for the marker.
// This will be displayed on taping the marker
markerOptions.title(addressText);
// Placing a marker on the touched position
googleMap.addMarker(markerOptions);
}
}
}
我的代码有问题吗?
【问题讨论】:
-
您添加了两次标记,一次是在单击地图时,一次是在地理编码完成后。您应该只在地理编码完成后添加它。并且不要为 markerOptions 保留类成员。在 onPostCreate 本地重新创建它。我觉得会更好。
标签: android google-maps-android-api-2