Android如何以后台Service的方式获取GPS数据

在配备Android系统的手机中，一般都配备了GPS设备。Android为我们获取GPS数据提供了很好的接口。本文来说一下如何使用Android获取GPS的经纬度。

1 从Service继承一个类。
2 创建startService()方法。
3 创建endService()方法 重载onCreate方法和onDestroy方法，并在这两个方法里面来调用startService以及endService。
4 在startService中，通过getSystemService方法获取Context.LOCATION_SERVICE。
5 基于LocationListener实现一个新类。默认将重载四个方法onLocationChanged、onProviderDisabled、onProviderEnabled、onStatusChanged。对于onLocationChanged方法是我们更新最新的GPS数据的方法。一般我们的操作都只需要在这里进行处理。
6 调用LocationManager的requestLocationUpdates方法，来定期触发获取GPS数据即可。在onLocationChanged函数里面可以实现我们对得到的经纬度的最终操作。
7 最后在我们的Activity里面通过按钮来启动Service，停止Service。

示意代码如下：

 

package com.jouhu.gpsservice;
 
import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Binder;
import android.os.IBinder;
import android.util.Log;
 
public class GPSService extends Service {
 
    //2000ms
    private static final long minTime = 2000;
    //最小变更距离 10m
    private static final float minDistance = 10;
 
    String tag = this.toString();
 
    private LocationManager locationManager;
    private LocationListener locationListener;
 
    private final IBinder mBinder = new GPSServiceBinder();
 
    public void startService()
    {
        locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
        locationListener = new GPSServiceListener();
        locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, minTime, minDistance, locationListener);
    }
 
    public void endService()
    {
        if(locationManager != null && locationListener != null)
        {
            locationManager.removeUpdates(locationListener);
        }
    }
 
    @Override
    public IBinder onBind(Intent arg0) {
        // TODO Auto-generated method stub
        return mBinder;
    }
 
    @Override
    public void onCreate()
    {
        //
        startService();
        Log.v(tag, "GPSService Started.");
    }
 
    @Override
    public void onDestroy()
    {
        endService();
        Log.v(tag, "GPSService Ended.");
    }
 
    public class GPSServiceBinder extends Binder {
        GPSService getService() {
            return GPSService.this;
        }
    }
}

 

GPSServiceListener的实现

 

package com.jouhu.gpsservice;
 
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.TimeZone;
 
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationProvider;
import android.os.Bundle;
import android.util.Log;
import android.widget.Toast;
 
public class GPSServiceListener implements LocationListener {
 
    private static final String tag = "GPSServiceListener";
    private static final float minAccuracyMeters = 35;
    private static final String hostUrl = "http://doandroid.info/gpsservice/position.php?";
    private static final String user = "huzhangyou";
    private static final String pass = "123456";
    private static final int duration = 10;
    private final DateFormat timestampFormat = new SimpleDateFormat("yyyyMMddHHmmss");
 
    public int GPSCurrentStatus;
 
    @Override
    public void onLocationChanged(Location location) {
        // TODO Auto-generated method stub
        if(location != null)
        {
            if (location.hasAccuracy() && location.getAccuracy() <= minAccuracyMeters)
            {
                //获取时间参数,将时间一并Post到服务器端
                GregorianCalendar greg = new GregorianCalendar();
                TimeZone tz = greg.getTimeZone();
                int offset = tz.getOffset(System.currentTimeMillis());
                greg.add(Calendar.SECOND, (offset/1000) * -1);
                StringBuffer strBuffer = new StringBuffer();
                strBuffer.append(hostUrl);
                strBuffer.append("user=");
                strBuffer.append(user);
                strBuffer.append("&pass=");
                strBuffer.append(pass);
                strBuffer.append("&Latitude=");
                strBuffer.append(location.getLatitude());
                strBuffer.append("&Longitude=");
                strBuffer.append(location.getLongitude());
                strBuffer.append("&Time=");
                strBuffer.append(timestampFormat.format(greg.getTime()));
                strBuffer.append("&Speed=");
                strBuffer.append(location.hasSpeed());
                doGet(strBuffer.toString());
                Log.v(tag, strBuffer.toString());
            }
        }
    }
 
    //将数据通过get的方式发送到服务器,服务器可以根据这个数据进行跟踪用户的行走状态
    private void doGet(String string) {
        // TODO Auto-generated method stub
        //
    }
 
    @Override
    public void onProviderDisabled(String provider) {
        // TODO Auto-generated method stub
    }
 
    @Override
    public void onProviderEnabled(String provider) {
        // TODO Auto-generated method stub
 
    }
 
    @Override
    public void onStatusChanged(String provider, int status, Bundle extras)
    {
        // TODO Auto-generated method stub
        GPSCurrentStatus = status;
    }
 
}

 

由于本文代码还没有完成，所以暂时不提供代码。感谢对博客的支持。

 

参考文章：
1 http://code.google.com/p/gpslogger/
2 http://developer.android.com/reference/android/location/Location.html
3 http://developer.android.com/guide/topics/location/obtaining-user-location.html

 

原文：http://doandroid.info/?p=1177