android - 无法在android中获取经度和纬度

Question

即使 GPS 打开并且网络已满，但有时我无法获得当前位置的纬度和纬度值，但有时我能够获得这些值，有时它显示的纬度和经度为 0....可以有人帮助我。

这是我正在使用的代码:

package com.fitness24.my24;
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.scheduleAtFixedRate(new GetLastLocation(), 0, 5000);
        return true;
    }

    public void removeGPS()
    {

        try {
            if(lm != null )
            {
                timer1.cancel();

                if(lm.isProviderEnabled(LocationManager.GPS_PROVIDER))
                {   
                lm.removeUpdates(locationListenerGps);
                locationListenerGps = null;
                }

                if(lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER))
                {   
                lm.removeUpdates(locationListenerNetwork);
                locationListenerNetwork = null;
                }


            lm = null;
            }
        } catch (Exception e) {

        } 
    }

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

            locationResult.gotLocation(location);

        }
        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) {

            locationResult.gotLocation(location);

        }
        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() {

             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);
    }
}

/////////////////getting current location///////////////////////////



private void getCurrentLocation(){


        try {

            Log.e("", "showmap location triggered" + Singleton.getSingletonForXml().sLat  + ""
                    + Singleton.getSingletonForXml().sLng);
            LocationResult locationResult = new LocationResult() {

                @Override
                public void gotLocation(Location location) {
                    // TODO Auto-generated method stub
                    if (location != null) {


                        Singleton.sLat = location.getLatitude();
                        Singleton.sLng= location.getLongitude();
                        Log.e("", "showmap location triggered" + Singleton.getSingletonForXml().sLat  + ""
                                + Singleton.getSingletonForXml().sLng);

                        if(myLocation != null)
                        {
                            myLocation.removeGPS();
                            Log.i("location", "location acheived and remove gps - inside");
                        }

                    }
                }

            };

            myLocation = new MyLocation();
            myLocation.getLocation(this, locationResult);
    }

Answer 1

我建议试试这段代码，我也用过这段代码，而且效果很好:

package com.fitness24.my24;

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){
            System.out.println("gps and/or network disabled");

          return false;
        }
        if(gps_enabled){
            System.out.println("gps enabled");
            lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListenerGps);
        }
        if(network_enabled)
            System.out.println("network enabled");
            lm.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListenerNetwork);
        timer1=new Timer();
        timer1.schedule(new GetLastLocation(), 25000);

        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);
    }
}

然后在你的主类中:

import com.fitness24.my24.MyLocation.LocationResult;
import android.location.Location;

然后也将此添加到您的主程序中，以调用/接收 gps:

private void locationClick() {
        myLocation.getLocation(this, locationResult);
    }

    public LocationResult locationResult = new LocationResult() {
        public void gotLocation(final Location location) {
            try {
            double lat = location.getLatitude();
            double lng = location.getLongitude();
                if (lat != 0.0 && lng != 0.0) {

                    String sLat;
                    String sLng;
                    sLat = Double.toString(lat);
                    sLng = Double.toString(lng);
                    gps_location = sLat+" "+sLng;
                    Toast.makeText(getBaseContext(), "We got gps location!", Toast.LENGTH_LONG)
                    .show();

                } 
            }catch (Exception e) {

            }
        }
    };

这个 locationClick() 在我的按钮的 onClick 事件上(调用/接收 gps 信息的按钮)

此外，不要忘记在您的 list 中添加:

 <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
 <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />