Question

我对Android很陌生，我从stackoverflow获取了一个代码片段来获取位置。它工作得很完美，但是当网络互联网被激活时，它会从那里获取坐标，并且它们不是很准确，或者根本没有（有时会达到5km +错误）。

我希望我的位置代码获取代码段仅获取GPS位置，但我目前的知识不允许我修改它以便我可以获得它。

以下是代码段：

package com.fourbox.bocterapp;

/**
 * Created by Soulstorm on 10/14/2014.
 */
import java.util.Timer;
import java.util.TimerTask;
import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;

public class MyLocation {
    Timer timer1;
    LocationManager lm;
    LocationResult locationResult;
    boolean gps_enabled=false;
    boolean network_enabled=false;

    public boolean getLocation(Context context, LocationResult result)
    {
        //I use LocationResult callback class to pass location value from MyLocation to user code.
        locationResult=result;
        if(lm==null)
            lm = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);

        //exceptions will be thrown if provider is not permitted.
        try{gps_enabled=lm.isProviderEnabled(LocationManager.GPS_PROVIDER);}catch(Exception ex){}
        try{network_enabled=lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER);}catch(Exception ex){}

        //don't start listeners if no provider is enabled
        if(!gps_enabled && !network_enabled)
            return false;

        if(gps_enabled)
            lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps);
        if(network_enabled)
            lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0,     locationListenerNetwork);
        timer1=new Timer();
        timer1.schedule(new GetLastLocation(), 50000);
        return true;
    }

    LocationListener locationListenerGps = new LocationListener() {
        public void onLocationChanged(Location location) {
            timer1.cancel();
            locationResult.gotLocation(location);
            lm.removeUpdates(this);
            lm.removeUpdates(locationListenerNetwork);
        }
        public void onProviderDisabled(String provider) {}
        public void onProviderEnabled(String provider) {}
        public void onStatusChanged(String provider, int status, Bundle extras) {}
    };

    LocationListener locationListenerNetwork = new LocationListener() {
        public void onLocationChanged(Location location) {
            timer1.cancel();
            locationResult.gotLocation(location);
            lm.removeUpdates(this);
            lm.removeUpdates(locationListenerGps);
        }
        public void onProviderDisabled(String provider) {}
        public void onProviderEnabled(String provider) {}
        public void onStatusChanged(String provider, int status, Bundle extras) {}
    };

    class GetLastLocation extends TimerTask {
        @Override
        public void run() {
            lm.removeUpdates(locationListenerGps);
            lm.removeUpdates(locationListenerNetwork);
            Location net_loc=null, gps_loc=null;
            if(gps_enabled)
                gps_loc=lm.getLastKnownLocation(LocationManager.GPS_PROVIDER);
            if(network_enabled)
                net_loc=lm.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);

            //if there are both values use the latest one
            if(gps_loc!=null && net_loc!=null){
                if(gps_loc.getTime()>net_loc.getTime())
                    locationResult.gotLocation(gps_loc);
                else
                    locationResult.gotLocation(net_loc);
                return;
            }

            if(gps_loc!=null){
                locationResult.gotLocation(gps_loc);
                return;
            }
            if(net_loc!=null){
                locationResult.gotLocation(net_loc);
                return;
            }
            locationResult.gotLocation(null);
        }
    }

    public static abstract class LocationResult{
        public abstract void gotLocation(Location location);

    }
}

以下是我如何使用它：

MyLocation.LocationResult locationResult = new MyLocation.LocationResult() {
                        @Override
                        public void gotLocation(Location location) {
                            currentUserLatitude = location.getLatitude();
                            currentUserLongitude = location.getLongitude();
                            new RemoteDataTask().execute();
                        }
                    };
                    MyLocation myLocation = new MyLocation();
                    myLocation.getLocation(this, locationResult);

你可以帮我修改我的代码，这样我的代码片段就不会获得网络坐标，只有GPS的坐标吗？

提前致谢！方面。

Answer 1

GetLastLocation类中的以下两行是您通过网络位置提供程序订阅位置更新的位置。

只需删除这两行代码，就不再接收来自网络位置提供商的更新。

if(network_enabled)
        lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0,     locationListenerNetwork);

请注意，GPS的位置更新可能比网络更长。因此，如果速度是一个问题，另一种方法是仍然使用网络位置更新，但过滤精度值。这看起来像这样：

LocationListener locationListenerNetwork = new LocationListener() {
    public void onLocationChanged(Location location) {

        if (location.getAccuracy() > THRESHOLD) {
            return;
        }

        timer1.cancel();
        locationResult.gotLocation(location);
        lm.removeUpdates(this);
        lm.removeUpdates(locationListenerGps);
    }
    public void onProviderDisabled(String provider) {}
    public void onProviderEnabled(String provider) {}
    public void onStatusChanged(String provider, int status, Bundle extras) {}
};

获得了获取位置的代码段，不想考虑网络位置

1 个答案: