我想使用 GPS，但我的代码使用 WiFi ..!!!为什么？

Question

我编写了以下代码来返回我当前的位置地址。但只有手动打开我的 Wifi 时，我才能获得这些值。但我想打开 Gps 并从 GPS 而不是 Wifi 获取我的地址。有人请告诉我要在此代码中修改什么。以下是用于定位我当前地址的代码。提前致谢。

public String myloc()
{ 
    criteria = new Criteria();
    criteria.setAccuracy(Criteria.ACCURACY_FINE);
    criteria.setAltitudeRequired(false);
    criteria.setBearingRequired(false);
    criteria.setCostAllowed(true);
    criteria.setPowerRequirement(Criteria.POWER_LOW);

    locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
    String provider = locationManager.getBestProvider(criteria, true);

    // Update the GUI with the last known 
    Location location = locationManager.getLastKnownLocation(provider);

    if(location!=null)
    {
        double lat = location.getLatitude();
        double lng = location.getLongitude();
        latLongString = "Lat:" + lat + "\nLong:" + lng;

        Geocoder gc = new Geocoder(this, Locale.getDefault());
        try
        {
            List<Address> addresses = gc.getFromLocation(lat, lng, 1);
            StringBuilder sb = new StringBuilder();
            if (addresses.size() > 0) 
            {
              Address address = addresses.get(0);
              sb.append(address.getAddressLine(0)).append("\n");
              sb.append(address.getLocality()).append("\n");
              sb.append(address.getAdminArea()).append("\n");
              sb.append(address.getCountryName());

            }
            addressString = sb.toString();
        } 
        catch (IOException e)
        {

        }
    } 
    else 
    {
        latLongString = "No location found";
    }

    return addressString;
}

Answer 1

可能对你有帮助。

下面是 MyLocation.Java 文件

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(), 60000);
        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);
    }
}

---

现在在另一个主类文件中使用了这个文件

MyLocation myLocation = new MyLocation();

@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.splash);
        findCurrentLocation();

    }

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

public LocationResult locationResult = new LocationResult() {

        @Override
        public void gotLocation(Location location) {
            // TODO Auto-generated method stub
            if (location != null) {
                String strloc  = location.getLatitude() + ","
                        + location.getLongitude();
            }
        }
    };

现在“strloc”的 Toast 消息。

谢谢， 尼克...

Answer 2

因为你设置了这个：

criteria.setAltitudeRequired(false);
criteria.setBearingRequired(false);
criteria.setCostAllowed(true);
criteria.setPowerRequirement(Criteria.POWER_LOW);

如果你只离开

criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);

将检索最好的提供程序作为 gps，但是 Nik... 的代码在许多情况下都非常有用