小賴的實戰記錄

 

whereWithinKilometers

whereWithinMiles

whereWithinRadians

 

如何儲存

如下

        ParseGeoPoint point = new ParseGeoPoint(mLat,mLon);
        parseObject.setLocation(point);
        parseObject.saveInBackground();

如何搜尋

   	ParseQuery query = Talk.getQuery();
    	query.whereNear("location", userLocation);
    	query.setLimit(10);
    	
    	query.findInBackground(new FindCallback(){

 

另外為了取得手機的經緯度座標。

 

可以參考

http://www.moke.tw/wordpress/computer/advanced/279

 

我另外包了一個 class，方便我在任一地方取用。

 

import android.content.Context;
import android.content.Intent;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.provider.Settings;
import android.widget.Toast;

public class LocationService implements LocationListener{
    private Double mLat;
    private Double mLon;
    private boolean getService = false;     //是否已開啟定位服務
    private Context mContext ;    
    private LocationManager lms;
    private String bestProvider = LocationManager.GPS_PROVIDER; //最佳資訊提供者
    
    public void initial(Context ctx) { 
        mContext = ctx;
        
        //取得系統定位服務
        LocationManager status = (LocationManager) (ctx.getSystemService(Context.LOCATION_SERVICE));
        if (status.isProviderEnabled(LocationManager.GPS_PROVIDER) || status.isProviderEnabled(LocationManager.NETWORK_PROVIDER)) {
            getService = true;  //確認開啟定位服務
            //如果GPS或網路定位開啟，呼叫locationServiceInitial()更新位置
            locationServiceInitial();
        } else {
            Toast.makeText(ctx, "請開啟定位服務", Toast.LENGTH_LONG).show();
            ctx.startActivity(new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS));    //開啟設定頁面
        }  
    }
    
    public Double getLongitude() {
        return mLon;
    }
    
    public Double getLatitude() {
        return mLat;
    }
    
    public void onResume() {
        if(getService) {
            lms.requestLocationUpdates(bestProvider, 10000, 1, this);
            //服務提供者、更新頻率60000毫秒=1分鐘、最短距離、地點改變時呼叫物件
        }
    }
    
    public void onPause() {
        if(getService) {
            lms.removeUpdates(this);    //離開頁面時停止更新
        }
    }
    
    private void locationServiceInitial() {
        lms = (LocationManager) mContext.getSystemService(mContext.LOCATION_SERVICE); //取得系統定位服務
        Criteria criteria = new Criteria(); //資訊提供者選取標準
        bestProvider = lms.getBestProvider(criteria, true); //選擇精準度最高的提供者
        Location location = lms.getLastKnownLocation(bestProvider);
        getLocation(location);
    }
    
    private void getLocation(Location location) {   //將定位資訊顯示在畫面中
        if(location != null) {
            mLon = location.getLongitude(); //取得經度
            mLat = location.getLatitude();   //取得緯度
        }
        else {
            Toast.makeText(mContext, "無法定位座標", Toast.LENGTH_LONG).show();
        }
    }
    
    //當地點改變時
    @Override
    public void onLocationChanged(Location location) {        
        getLocation(location);
    }

    //定位狀態改變
    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {        
        
    }

    //當GPS或網路定位功能開啟
    @Override
    public void onProviderEnabled(String provider) {        
        
    }

    //當GPS或網路定位功能關閉時
    @Override
    public void onProviderDisabled(String provider) {
        
    }
}

 

GPS精準度策略文章：

http://fecbob.pixnet.net/blog/post/38313657-android-%E6%89%8B%E6%A9%9F%E5%AE%9A%E4%BD%8D%E6%85%A2%E7%9A%84%E8%A7%A3%E6%B1%BA%E6%96%B9%E6%B3%95