在玩一个GPS的东西 获取Location一直为null  后来是从onLocationChanged里面拿location才搞定了   贴一下吧  代码太乱

  1. /**

  2. * 主要是用户定位操作

  3. *@author hope

  4. */

  5. package com.jeedroid.tools;  


  6. import java.io.IOException;  

  7. import java.util.List;  

  8. import java.util.Locale;  


  9. import android.content.Context;  

  10. import android.location.Address;  

  11. import android.location.Criteria;  

  12. import android.location.Geocoder;  

  13. import android.location.Location;  

  14. import android.location.LocationListener;  

  15. import android.location.LocationManager;  

  16. import android.os.Bundle;  

  17. import android.provider.Settings;  

  18. import android.util.Log;  


  19. publicclass LocationTools  

  20. {  

  21. private Location location;  

  22. publicstatic LocationManager getLocationManager(Context context)  

  23. {  

  24. return (LocationManager) context.getSystemService(context.LOCATION_SERVICE);  

  25. }  

  26. //获取位置信息

  27. public String getAddress(Context context)  

  28. {  

  29.    LocationManager locationManager = this.getLocationManager(context);  

  30. if(!locationManager.isProviderEnabled(android.location.LocationManager.GPS_PROVIDER))  

  31.    {  

  32. //打开GPS 需Android2.2以上系统支持

  33.    android.provider.Settings.Secure.setLocationProviderEnabled(context.getContentResolver(), LocationManager.GPS_PROVIDER, false);  

  34.    }  

  35. return doWork(context);  

  36. }  


  37. private String doWork(Context context)  

  38. {  

  39.    String addres="";  

  40.    LocationManager locationManager = this.getLocationManager(context);  

  41.    Criteria criteria = new Criteria();  

  42. // 获得最好的定位效果  

  43.    criteria.setAccuracy(Criteria.ACCURACY_FINE);    

  44.    criteria.setAltitudeRequired(false);    

  45.    criteria.setBearingRequired(false);    

  46.    criteria.setCostAllowed(false);    

  47. // 使用省电模式  

  48.    criteria.setPowerRequirement(Criteria.POWER_LOW);    

  49.    String provider =locationManager.getBestProvider(criteria, true);  

  50.    Log.i("provider>>>>>>", provider);  

  51. //获得当前位置  location为空是一直取  从onLocationChanged里面取

  52. while(location==null)  

  53.    {  

  54.    location =locationManager.getLastKnownLocation(provider);  

  55.    }  

  56. //locationListener

  57.    LocationListener locationListener = new LocationListener()  

  58.    {  


  59. @Override

  60. publicvoid onLocationChanged(Location location)  

  61.        {  

  62.            LocationTools.this.location=location;  

  63.        }  


  64. @Override

  65. publicvoid onProviderDisabled(String provider)  

  66.        {  


  67.        }  


  68. @Override

  69. publicvoid onProviderEnabled(String provider)  

  70.        {  


  71.        }  


  72. @Override

  73. publicvoid onStatusChanged(String provider, int status, Bundle extras)  

  74.        {  


  75.        }  


  76.    };  

  77.    locationManager.requestLocationUpdates(provider, 1000, 10, locationListener);  


  78.    Geocoder geo = new Geocoder(context,Locale.getDefault());  

  79. try

  80.    {  

  81.        List<Address> address=geo.getFromLocation(location.getLatitude(), location.getLongitude(), 1);  

  82. if(address.size()>0)  

  83.        {  

  84.            addres=address.get(0).getAddressLine(0);  

  85.        }  

  86.    } catch (IOException e)  

  87.    {  

  88. // TODO Auto-generated catch block

  89.        e.printStackTrace();  

  90.    }  

  91. return addres;  

  92. }  

  93. }  



今天弄了一个多小时,写了一个GPS获取地理位置代码的小例子,包括参考了网上的一些代码,并且对代码进行了一些修改,希望对大家的帮助。具体代码如下:  要实用Adnroid平台的GPS设备,首先需要添加上权限,所以需要添加如下权限:  


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


具体实现代码如下:

首先判断GPS模块是否存在或者是开启:


复制代码
ContractedBlock.gif ExpandedBlockStart.gif 代码
privatevoid openGPSSettings() {
LocationManager alm = (LocationManager) this
.getSystemService(Context.LOCATION_SERVICE);
if (alm
.isProviderEnabled(android.location.LocationManager.GPS_PROVIDER)) {
Toast.makeText(this, "GPS模块正常", Toast.LENGTH_SHORT)
.show();
return;
}

Toast.makeText(this, "请开启GPS!", Toast.LENGTH_SHORT).show();
Intent intent = new Intent(Settings.ACTION_SECURITY_SETTINGS);
startActivityForResult(intent,0); //此为设置完成后返回到获取界面

}
复制代码


如果开启正常,则会直接进入到显示页面,如果开启不正常,则会进行到GPS设置页面:

获取代码如下:


按 Ctrl+C 复制代码
代码 private void getLocation() { // 获取位置管理服务 LocationManager locationManager; String serviceName = Context.LOCATION_SERVICE; locationManager = (LocationManager) this.getSystemService(serviceName); // 查找到服务信息 Criteria criteria = new Criteria(); criteria.setAccuracy(Criteria.ACCURACY_FINE); // 高精度 criteria.setAltitudeRequired(false); criteria.setBearingRequired(false); criteria.setCostAllowed(true); criteria.setPowerRequirement(Criteria.POWER_LOW); // 低功耗 String provider = locationManager.getBestProvider(criteria, true); // 获取GPS信息 Location location = locationManager.getLastKnownLocation(provider); // 通过GPS获取位置 updateToNewLocation(location); // 设置监听器,自动更新的最小时间为间隔N秒(1秒为1*1000,这样写主要为了方便)或最小位移变化超过N米 locationManager.requestLocationUpdates(provider, 100 * 1000, 500, locationListener); }
按 Ctrl+C 复制代码

到这里就可以获取到地理位置信息了,但是还是要显示出来,那么就用下面的方法进行显示:



复制代码
ContractedBlock.gif ExpandedBlockStart.gif 代码
privatevoid updateToNewLocation(Location location) {

TextView tv1;
tv1 = (TextView) this.findViewById(R.id.tv1);
if (location != null) {
double latitude = location.getLatitude();
double longitude= location.getLongitude();
tv1.setText("维度:" + latitude+ "\n经度" + longitude);
} else {
tv1.setText("无法获取地理信息");
}

}


android gps打开和关闭  

http://blog.youkuaiyun.com/zfzf294990051/article/details/7393966

android gps开发(mrGPS源代码)

http://blog.youkuaiyun.com/mrandexe/article/details/6621125


Android GPS 定位的实现(1)

http://www.cnblogs.com/fly_binbin/archive/2010/12/16/1908518.html

Android 强制开启GPS

http://download.youkuaiyun.com/detail/liqingang/4350556

Android判断GPS是否开启和强制帮用户打开GPS

http://blog.youkuaiyun.com/android_ls/article/details/8605931

关于4.0强制开启GPS定位

http://www.eoeandroid.com/thread-199085-1-1.html