我想在一项活动中获取我的位置，然后将其发送到另一个活动（当我单击按钮时），然后在地图上显示我的位置。这是我的代码（问题是，地图没有动画到我当前的位置，我相信第一个活动没有获得当前位置并将 null 发送到第二个活动）：
public class ActivityMain extends MapActivity {
private LocationManager locationManager;
private LocationListener locationListener;
private GeoPoint currentGeoPoint = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activitymain);
try{
locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
locationListener = new getLocation();
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
}
catch (NullPointerException e){
System.out.println("Null");
e.printStackTrace();
}
catch (Exception e) {
e.printStackTrace();
}
}
public void onButton1Click(View view) {
Intent intent = new Intent(ActivityMain.this, ActivityMap.class);
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
if(currentGeoPoint != null){
intent.putExtra("lat", currentGeoPoint.getLatitudeE6());
intent.putExtra("long", currentGeoPoint.getLongitudeE6());
}
else{
try{
locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);
locationListener = new getLocation();
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
}
catch (NullPointerException e){
System.out.println("Null");
e.printStackTrace();
}
catch (Exception e) {
e.printStackTrace();
}
}
Context c = getApplicationContext();
c.startActivity(intent);
//Intent intent = new Intent(ActivityMain.this, ActivityMap.class);
//this.startActivity(intent);
}
public void onButton2Clik (View view){
Intent intent = new Intent(ActivityMain.this, ActivityListCategories.class);
this.startActivity(intent);
}
class getLocation implements LocationListener {
public void onLocationChanged(Location location) {
if (location != null){
GeoPoint currentPoint = getCurrentPoint(location);
currentGeoPoint = currentPoint;
}
}
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
public void onProviderEnabled(String provider) {
Toast.makeText(getApplicationContext(), getProvider() + " enabled", Toast.LENGTH_SHORT).show();
}
public void onProviderDisabled(String provider) {
Toast.makeText(getApplicationContext(), getProvider() + " disabled", Toast.LENGTH_SHORT).show();
}
}
public GeoPoint getLastKnownPoint (){
GeoPoint lastKnownPoint = null;
Location lastKnownLocation = locationManager.getLastKnownLocation(getProvider());
if(lastKnownLocation != null){
lastKnownPoint = getCurrentPoint(lastKnownLocation);
}
return lastKnownPoint;
}
public GeoPoint getCurrentPoint (Location location){
GeoPoint currentPoint = new GeoPoint((int)(location.getLatitude()*1E6),(int)(location.getLongitude()*1E6));
return currentPoint;
}
public String getProvider() {
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
criteria.setPowerRequirement(Criteria.NO_REQUIREMENT);
criteria.setAccuracy(Criteria.NO_REQUIREMENT);
String Provider = locationManager.getBestProvider(criteria, true);
return Provider;
}
@Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
protected void onResume(){
super.onResume();
LocationManager newLocationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager = newLocationManager;
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);
}
protected void onPause(){
super.onPause();
locationManager.removeUpdates(locationListener);
}
protected void onDestroy(){
super.onDestroy();
locationManager.removeUpdates(locationListener);
}
}
这是第二个活动的代码
public class ActivityMap extends MapActivity {
private MapController mapController;
private MapView mapView;
private LocationManager locationManager;
private LocationListener locationListener;
private GeoPoint currentGeoPoint;
private Location currentLocation = null;
private ClassMapOverlay currPos;
private ClassCustomItemizedOverlay<ClassCustomOverlayItem> mallsOverlay;
private List<ClassMall> malls;
// TODO: AsyncTAsk
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activitymap);
Bundle bundle = getIntent().getExtras();
if(bundle != null){
currentGeoPoint = new GeoPoint((int)(bundle.getDouble("lat") / 1E6),(int)(bundle.getDouble("long")/1E6));
animateToCurrentPoint(currentGeoPoint);
}
mapView = (MapView) findViewById(R.id.mapView);
mapController = mapView.getController();
public GeoPoint getLastKnownPoint (){
GeoPoint lastKnownPoint = null;
Location lastKnownLocation = locationManager.getLastKnownLocation(getProvider());
if(lastKnownLocation != null){
lastKnownPoint = getCurrentPoint(lastKnownLocation);
}
return lastKnownPoint;
}
public GeoPoint getCurrentPoint (Location location){
GeoPoint currentPoint = new GeoPoint((int)(location.getLatitude()*1E6),(int)(location.getLongitude()*1E6));
return currentPoint;
}
public void animateToCurrentPoint(GeoPoint currentPoint){
mapController.animateTo(currentPoint);
mapController.setCenter(currentPoint);
mapController.setZoom(15);
}
public void drawCurrPositionOverlay(){
List<Overlay> overlays = mapView.getOverlays();
overlays.remove(currPos);
Drawable marker = getResources().getDrawable(R.drawable.me);
currPos = new ClassMapOverlay(marker,mapView);
GeoPoint drawMyPoint = null;
if(currentGeoPoint==null){
drawMyPoint = getLastKnownPoint();
}
else {
drawMyPoint = currentGeoPoint;
}
OverlayItem overlayitem = new OverlayItem(drawMyPoint, "Moja adresa:", getAddress(currentLocation));
currPos.addOverlay(overlayitem);
overlays.add(currPos);
currPos.setCurrentLocation(currentLocation);
}
public void drawMallsOverlay(List <ClassMall> malls){
List <Overlay> overlays = mapView.getOverlays();
overlays.remove(mallsOverlay);
Drawable marker = getResources().getDrawable(R.drawable.malls);
mallsOverlay = new ClassCustomItemizedOverlay<ClassCustomOverlayItem>(marker, mapView);
if(malls.size() > 0){
for(ClassMall temp: malls ){
GeoPoint mallPoint = getLatLon(temp.getAddress());
ClassCustomOverlayItem overlayItem = new ClassCustomOverlayItem(mallPoint,temp.getName(),temp.getAddress(), temp.getUrl());
mallsOverlay.addOverlay(overlayItem);
//Toast.makeText(getApplicationContext(), temp, Toast.LENGTH_SHORT).show();
}
}
overlays.add(mallsOverlay);
}
public String getProvider() {
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
criteria.setPowerRequirement(Criteria.NO_REQUIREMENT);
criteria.setAccuracy(Criteria.NO_REQUIREMENT);
String Provider = locationManager.getBestProvider(criteria, true);
return Provider;
}
public String getAddress (Location location){
Geocoder geoCoder = new Geocoder(getApplicationContext(), Locale.getDefault());
String sAddress = "";
try{
List <Address> address = geoCoder.getFromLocation(location.getLatitude(), location.getLongitude(), 1);
if(address.size() > 0){
for(int i = 0; i < address.get(0).getMaxAddressLineIndex(); i++){
sAddress += address.get(0).getAddressLine(i) + "\n";
}
}
}
catch (IOException e){
e.printStackTrace();
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_SHORT).show();
}
return sAddress;
}
public GeoPoint getLatLon (String address){
Geocoder geoCoder = new Geocoder(this, Locale.getDefault());
GeoPoint point = null;
List <Address> addresses = null;
try {
addresses = geoCoder.getFromLocationName(address, 1);
if(addresses.size() > 0){
point = new GeoPoint((int) (addresses.get(0).getLatitude() * 1E6),
(int) (addresses.get(0).getLongitude()*1E6));
}
} catch (IOException e) {
e.printStackTrace();
Toast.makeText(getApplicationContext(), e.toString(), Toast.LENGTH_SHORT).show();
}
return point;
}
@Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
}
请你告诉我如何异步获取我的当前位置？