Android使用criteria选择合适的地理位置服务实现方法

/* LocationActivity.java * @author octobershiner * 2011 7 24 * SE.HIT * 利用Criteria选择最优的位置服务，演示定位用户的位置并且监听位置变化的代码 * */package uni.location;import android.app.Activity;import android.content.Context;import android.location.Criteria;import android.location.Location;import android.location.LocationListener;import android.location.LocationManager;import android.os.Bundle;import android.os.Vibrator;import android.util.Log;import android.widget.TextView;public class LocationActivity extends Activity {  /** Called when the activity is first created. */  //创建lcoationManager对象  private LocationManager manager;  private static final String TAG = "LOCATION DEMO";  @Override  public void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.main);    //获取系统的服务，    manager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);    //创建一个criteria对象    Criteria criteria = new Criteria();    criteria.setAccuracy(Criteria.ACCURACY_COARSE);    //设置不需要获取海拔方向数据    criteria.setAltitudeRequired(false);    criteria.setBearingRequired(false);    //设置允许产生资费    criteria.setCostAllowed(true);    //要求低耗电    criteria.setPowerRequirement(Criteria.POWER_LOW);    String provider = manager.getBestProvider(criteria, false);    Log.i(TAG, "we choose "+ provider);    Location location = manager.getLastKnownLocation(provider);    //第一次获得设备的位置    updateLocation(location);    //重要函数，监听数据测试    manager.requestLocationUpdates(provider, 6000, 10,            locationListener);  }  //创建一个事件监听器  private final LocationListener locationListener = new LocationListener() {      public void onLocationChanged(Location location) {      updateLocation(location);      }      public void onProviderDisabled(String provider){        updateLocation(null);        Log.i(TAG, "Provider now is disabled..");      }      public void onProviderEnabled(String provider){        Log.i(TAG, "Provider now is enabled..");      }      public void onStatusChanged(String provider, int status,Bundle extras){ }  };  //获取用户位置的函数，利用Log显示  private void updateLocation(Location location) {      String latLng;      if (location != null) {      double lat = location.getLatitude();      double lng = location.getLongitude();      latLng = "Latitude:" + lat + " Longitude:" + lng;      } else {      latLng = "Can't access your location";      }      Log.i(TAG, "The location has changed..");      Log.i(TAG, "Your Location:" +latLng);  }}

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"   package="uni.location"   android:versionCode="1"   android:versionName="1.0">  <uses-sdk android:minSdkVersion="8" />  <application android:icon="@drawable/icon" android:label="@string/app_name">    <activity android:name=".LocationActivity"         android:label="@string/app_name">      <intent-filter>        <action android:name="android.intent.action.MAIN" />        <category android:name="android.intent.category.LAUNCHER" />      </intent-filter>    </activity>  </application>    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /></manifest>