0

看起来我遇到了某种奇怪的变量设置问题。我有一个 LocationListener 可以正确更新并正确设置当前位置。我尝试设置包含当前纬度/经度的全局变量，但它有点失败（在我发布一些代码后会详细介绍）。

我有一个片段

public class MyMap extends MapFragment {
    private LocationManager mLocManager;
    private LocationListener myLocationListener;
    protected volatile double lat;//Place to hold variable
    protected volatile double lon;//Place to hold variable

    public void onActivityCreated(Bundled savedInstanceState) {
    super.onActivityCreated(savedInstanceState);
    int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this.getActivity().getApplicationContext());
    if (resultCode == ConnectionResult.SUCCESS){

        if(gmap == null){
            gmap = this.getMap();
            if(gmap != null){
                gmap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
                gmap.setOnMarkerDragListener(this);
                gmap.setMyLocationEnabled(true);
                gmap.setOnMapLongClickListener(this);
            }else{
                return;
            }
        }
    }else{
        GooglePlayServicesUtil.getErrorDialog(resultCode, this.getActivity(), RQS_GooglePlayServices);
    }
    distance = 100;
    myLocationListener = new MyLocationListener();
    mLocManager = (LocationManager) this.getActivity().getSystemService(Context.LOCATION_SERVICE);
}

@Override
public void onResume() {
    super.onResume();
    mLocManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 500,10, myLocationListener);
    mLocManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 500, 10, myLocationListener);
    mLocManager.getLastKnownLocation(Context.LOCATION_SERVICE);

} 

@Override
public void onPause() {
    super.onPause();
    mLocManager.removeUpdates(myLocationListener);
}

//Listen for location changes and update the map with that information
private class MyLocationListener implements LocationListener {

    @Override
    public void onLocationChanged(Location location) {
        if (Math.abs(location.getLatitude()) > 0.0 && Math.abs(location.getLongitude()) > 0.0) {
            lat = location.getLatitude();
            lon = location.getLongitude();
        }
        //This reports correctly
        Log.v("Magic", "LOCATION CHANGED!" + "\nLat: " + Double.toString(lat) + "\nLon: " +  Double.toString(lon));
        if (!currentLocationSet) {
            gmap.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(lat, lon), 15));
            currentLocationSet = true;
        }
    }

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {

    }

    @Override
    public void onProviderEnabled(String provider) {

    }

    @Override
    public void onProviderDisabled(String provider) {

    }
}
public void newPlace(final UpdatePlacesCallBack upc, Place p) {
    //This gives me 0.0 for both variables.
    Log.v("Magic", "Name: " + p.getName() + "\nLat: " + Double.toString(lat) + "\nLon:" + Double.toString(lon));
}       

}

所以，当我从 LocationListener 中看到日志时，它会记录正确的位置，但是如果我尝试检索双纬度和双倍经度的值，它会为这两个变量返回 0.0。

4

1 回答 1

1 
// try this
public static LocationManager mlocManager;
public static LocationListner mListner;
private static String latitude;
public static String longitude;
private Location currentLocation;

public Location getCurrentLocation() {
  return currentLocation;
}

public void setCurrentLocation(Location currentLocation) {
   this.currentLocation = currentLocation;
}

try {
mlocManager = (LocationManager) getSystemService(Activity.LOCATION_SERVICE);
                mListner = new LocationListner();
                runOnUiThread(new Runnable() {

                    @Override
                    public void run() {
                        try {
                        try {
                            mlocManager.requestLocationUpdates(LocationManager.PASSIVE_PROVIDER, 0, 0, mListner);
                        } catch (Throwable e) {
                            e.printStackTrace();
                        }

                            mlocManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, mListner);
                        } catch (Throwable e) {
                            e.printStackTrace();
                        }
                        try {
                            mlocManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, mListner);
                        } catch (Throwable e) {
                            e.printStackTrace();
                        }

                    }
                });
} catch (Throwable e) {
    e.printStackTrace();
}

    public String getLatitude() {
        if (latitude != null) {
            return latitude;
        }
        Location loc = mlocManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
        if (loc == null) {
            loc = mlocManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
            if (loc == null) {
                loc = mlocManager.getLastKnownLocation(LocationManager.PASSIVE_PROVIDER);
            }
            if (loc != null) {
                return "" + loc.getLatitude();
            }
        } else {
            return "" + loc.getLatitude();
        }
        return "0.0";
    }

    public void setLatitude(String latitide) {
        latitude = latitide;
    }

    public String getLongitude() {
        if (longitude != null) {
            return longitude;
        }
        Location loc = mlocManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
        if (loc == null) {
            loc = mlocManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
            if (loc == null) {
                loc = mlocManager.getLastKnownLocation(LocationManager.PASSIVE_PROVIDER);
            }
            if (loc != null) {
                return "" + loc.getLongitude();
            }
        } else {
            return "" + loc.getLongitude();
        }
        return "0.0";
    }

    public void setLongitude(String longitude) {
        SmartActivity.longitude = longitude;
    }

    class LocationListner implements LocationListener {

        @Override
        public void onLocationChanged(Location location) {
            setLatitude("" + location.getLatitude());
            setLongitude("" + location.getLongitude());
            setCurrentLocation(location);
        }

        @Override
        public void onProviderDisabled(String provider) {
        }

        @Override
        public void onProviderEnabled(String provider) {
        }

        @Override
        public void onStatusChanged(String provider, int status, Bundle extras) {
        }

    }
于 2013-10-30T03:58:46.113 回答