Question

新MapView / GoogleMap（Google Maps Android API V2）的默认行为是仅使用GPS位置。在室内通常意味着根本没有位置。当我的应用程序显示MapView时，我需要当前（最后已知，最佳猜测等）位置立即居中/缩放，并且地图的MyLocationButton始终可用。我不需要为任何其他目的跟踪位置更改。

在这里，为GoogleMap授予所有位置提供程序比使用自定义LocationSource类的GoogleMap.setLocationSource（）更简单吗？我在这里看到了LocationSource示例https://stackoverflow.com/a/14389975/935242以及其他类似示例，它们使用了Google不再推荐的旧API。建议使用Google Play服务，但为了确保网络提供的位置，我们应该使用旧工具吗？

Answer 1

以下是您完整的解决方案。在代码下方您想要获取位置

LocationResult locationResult = new LocationResult(){
                @Override
                public void gotLocation(Location location) {
                    // TODO Auto-generated method stub
                    Latitude=location.getLatitude();
                    longitude=location.getLongitude();
                    Log.d("latitude",""+Latitude);
                    Log.d("latitude",""+longitude);
                }
            };
            MyLocation myLocation = new MyLocation();
            myLocation.getLocation(this, locationResult);

并创建一个MyLocation类以查找位置lat long

package com.example.util;

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;

import com.example.pgapplication.SearchResultActivity;

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

    public boolean getLocation(SearchResultActivity searchResultActivity, LocationResult result)
    {
        //I use LocationResult callback class to pass location value from MyLocation to user code.
        locationResult=result;
        if(lm==null)
            lm = (LocationManager) searchResultActivity.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(),0);
        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);
    }
}

使用所有位置提供商的Google Map

1 个答案: