我正在开发一个场景，我必须在MapActivity上的列表视图中显示最近位置的地址。但是在成功运行我的代码后，列表将不会出现在MapActivity上。
这是我的代码：
public class GMapActivity extends com.google.android.maps.MapActivity implements OnClickListener{
MapView _mapView;
private static int latitudeE6 = 37985339;
private static int longitudeE6 = 23716735;
private GpsListener _gpsLister=new GpsListener();
List<Overlay> overlayList;
MapController controller;
Button _cancelBtn;
String returnAddress = "";
ListView locationListView;
ArrayList<String> locationAddressArrayList=new ArrayList<String>();
ArrayAdapter<String> locationAdapter;
LocationListAdapter locationListAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mapscreen);
_mapView=(MapView)findViewById(R.id.mapView);
_mapView.setBuiltInZoomControls(true);
_cancelBtn=(Button)findViewById(R.id.cancel_button);
_cancelBtn.setOnClickListener(this);
locationListView=(ListView)findViewById(R.id.location_listview);
/*locationAdapter=new ArrayAdapter<String>(GMapActivity.this, android.R.layout.simple_list_item_1, locationAddressArrayList);*/
locationListAdapter=new LocationListAdapter(GMapActivity.this, locationAddressArrayList);
locationAddressArrayList.add("RNT Marg");
locationAddressArrayList.add("RNT Marg");
locationAddressArrayList.add("RNT Marg");
locationAddressArrayList.add("RNT Marg");
locationAddressArrayList.add("RNT Marg");
locationAddressArrayList.add("RNT Marg");
locationListView.setAdapter(locationListAdapter);
///////////////START GPS/////////////////
if(Constant.isGpsStarted==false){
startGPS();
latitudeE6=(int)Constant.latitudeValue;
longitudeE6=(int)Constant.longitudeValue;
}
//GetAddress(Constant.latitudeValue, Constant.longitudeValue);
/////////////////////////////////////////
////////////////////////////////GET NEAREST LOCATIONS/////////////////////////////
LocationManager locationManager = (LocationManager) GMapActivity.this
.getSystemService(Context.LOCATION_SERVICE);
LocationListener locationListener = new LocationListener() {
public void onStatusChanged(String provider, int status,
Bundle extras) {
}
public void onProviderEnabled(String provider) {
}
public void onProviderDisabled(String provider) {
}
public void onLocationChanged(Location location) {
Double l1 = location.getLatitude();
Double l2 = location.getLongitude();
//GetAddress(l1, l2);
}
};
locationManager.requestLocationUpdates(
LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
//////////////////////////////////////////////////////////////////////////////////
List mapOverlays = _mapView.getOverlays();
Drawable drawable = this.getResources().getDrawable(R.drawable.mapping);
CustomItemizedOverlay itemizedOverlay =
new CustomItemizedOverlay(drawable, this);
GeoPoint point = new GeoPoint(latitudeE6, longitudeE6);
OverlayItem overlayitem =
new OverlayItem(point, ""+Constant.latitudeValue, ""+Constant.longitudeValue);
itemizedOverlay.addOverlay(overlayitem);
mapOverlays.add(itemizedOverlay);
MapController mapController = _mapView.getController();
mapController.animateTo(point);
mapController.setZoom(6);
/*overlayList = _mapView.getOverlays();
Drawable drawable = this.getResources().getDrawable(R.drawable.mapping);
CustomPinPoint itemizedoverlay = new CustomPinPoint(drawable,this);
double lat_coordinates[] ={27.700556,28.2642635,30.0018168,29.776669,29.4096819,29.4560611};
double lng_coordinates[] ={85.3630,83.9735195,80.7382742,81.2518833,81.8115051,80.5403779};
String place_name[] ={"kathmandu","Pokhara","Darchula","Bajhang","Bajura","Baitadi"};
String place_info[] ={"Its an capital of Nepal","Its and tourist place of Nepal","Its one of the beautiful place in country side","CHD District Target:10 51,960, VDCs/Muncipalities reported:41/41","CHD District Target: 71,280, VDCs/Muncipalities reported: 47/47","CHD District Target:10 51,960, VDCs/Muncipalities reported:41/41","CHD District Target: 71,280, VDCs/Muncipalities reported: 7/7","CHD District Target:10 21,960, VDCs/Muncipalities reported:44/41","CHD District Target: 33,3123, VDCs/Muncipalities reported: 47/47"};
try{
for(int i=0; i<place_name.length; i++)
{
GeoPoint point = new GeoPoint((int)(lat_coordinates[i]*1E6),(int)(lng_coordinates[i]*1E6));
OverlayItem overlayitem = new OverlayItem(point, place_name[i], place_info[i]);
itemizedoverlay.addOverlay(overlayitem);
}
}catch(NullPointerException e){
e.getStackTrace();
}
finally{
overlayList.add(itemizedoverlay);
}
controller = _mapView.getController();
controller.animateTo(new GeoPoint((int)(lat_coordinates[0]*1E6),(int)(lng_coordinates[0]*1E6)));
controller.setZoom(8);*/
}
//START GPS
public void startGPS(){
Constant.isGpsStarted = true;
_gpsLister.startGpsCallBack(GMapActivity.this);
_gpsLister.stopGpsCallBack();
_gpsLister.startGpsCallbackAgain(GMapActivity.this);
}
@Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
public void onClick(View v) {
switch (v.getId()) {
case R.id.cancel_button:
this.finish();
break;
default:
break;
}
}
public void getNearestLocations(){
}
private void GetAddress(final Double lat, final Double lon) {
Constant.progressDialog = ProgressDialog.show(GMapActivity.this,"", "Please wait...");
new Thread(){
public void run() {
Geocoder geocoder = new Geocoder(GMapActivity.this, Locale.ENGLISH);
List<Address> addresses = null;
try {
addresses = geocoder.getFromLocation(lat, lon, 1);
if (!addresses.equals(null)) {
Address returnedAddress = addresses.get(0);
StringBuilder strReturnedAddress = new StringBuilder("\n");
for (int i = 0; i < returnedAddress.getMaxAddressLineIndex(); i++) {
locationAddressArrayList.add((String)returnedAddress.getAddressLine(i));
strReturnedAddress
.append(returnedAddress.getAddressLine(i)).append(
"\n");
}
returnAddress = "Around: " + strReturnedAddress.toString();
} else {
returnAddress = "No Address returned!";
}
} catch (IOException e) {
e.printStackTrace();
returnAddress = "Location: https://maps.google.co.in/maps?hl=en&q=" + lat
+ "," + lon;
} catch (NullPointerException e) {
e.printStackTrace();
returnAddress = lat + "," + lon;
}
runOnUiThread(new Runnable() {
public void run() {
locationAdapter.notifyDataSetChanged();
locationListView.setAdapter(locationAdapter);
Constant.progressDialog.cancel();
}
});
};
}.start();
// return returnAddress;
}
}