Location获取地理位置信息（中）Criteria类的简单使用

 

LocationActivity.java

 

/*  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); 

    } 

     

} 

 

同时修改manifest.xml文件添加权限    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> 

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