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我正在开发一个使用 AddProximityAlert 方法的 Android 项目,因为您已经知道此方法可让您为位置(纬度、经度)和给定半径给出的位置设置接近警报,并通知您如果您离它这么近。

所以我三天前一直在努力,我一次又一次地遇到同样的问题..

在 bref:这是我的简单代码。

#MainActivity.java

package com.example.proximityalert;

import android.app.Activity;
import android.app.PendingIntent;
import android.content.Intent;
import android.content.IntentFilter;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.util.Log;

public class MainActivity extends Activity implements LocationListener {

    LocationManager lm;

    //Defining Latitude & Longitude
    double lat=37.422006 ,long1=-122.084095;
    //Defining Radius
    float radius=1000;               

    //Intent Action 
    String ACTION_FILTER = "com.example.proximityalert";


   @Override
   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);

       //i'm registering my Receiver First
       registerReceiver(new ProximityReciever(), new IntentFilter(ACTION_FILTER));

       //i'm calling ther service Location Manager
       lm=(LocationManager) getSystemService(LOCATION_SERVICE);

       //for debugging...
       lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000, 10, this);

       //Setting up My Broadcast Intent
       Intent i= new Intent(ACTION_FILTER);
       PendingIntent pi = PendingIntent.getBroadcast(getApplicationContext(), -1, i, 0);

       //setting up proximituMethod
       lm.addProximityAlert(lat, long1, radius, -1, pi);

   }

@Override
//just For debugging to See the distance between my actual position and the aproximit point  
public void onLocationChanged(Location newLocation) {

    Location old = new Location("OLD");
    old.setLatitude(lat);
    old.setLongitude(long1);

    double distance = newLocation.distanceTo(old);

    Log.i("MyTag", "Distance: " + distance);
}

@Override
public void onProviderDisabled(String arg0) {}

@Override
public void onProviderEnabled(String arg0) {}

@Override
public void onStatusChanged(String arg0, int arg1, Bundle arg2) {}

}

#ProximityReceiver.java

package com.example.proximityalert;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.location.LocationManager;
import android.util.Log;
import android.widget.Toast;


public class ProximityReciever extends BroadcastReceiver {

     @Override
     public void onReceive(Context context, Intent intent) {

         // Key for determining whether user is leaving or entering 
         String key = LocationManager.KEY_PROXIMITY_ENTERING;

         //Gives whether the user is entering or leaving in boolean form  
         boolean state = intent.getBooleanExtra(key, false);

          if(state){
                // Call the Notification Service or anything else that you would like to do here
                Log.i("MyTag", "Welcome to my Area");
                Toast.makeText(context, "Welcome to my Area", Toast.LENGTH_SHORT).show();
          }else{
              //Other custom Notification 
                Log.i("MyTag", "Thank you for visiting my Area,come back again !!");
                Toast.makeText(context, "Thank you for visiting my Area,come back again !!", Toast.LENGTH_SHORT).show();
          }
     }
}

*#问题是当我运行程序时,系统从未调用过 BroadcastReceiver(ProximityReciever),即使我非常接近接近点,即使调试器显示两个位置之间的距离 < 1000m :/

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1 回答 1

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我刚刚弄清楚了关于这个主题的一些事情以及为什么 addProximityAlert 无法正常工作,我与你分享这个,因为我注意到有些人之前问过同样的问题,但他们没有得到任何答案!

答案就在眼前但我没注意,所以在阅读Android官方文档(here)时看到了这句话“由于位置估计的近似性质,如果设备通过简单地给定区域,可能不会触发任何 Intent

那什么意识?这意味着当您在 AVD 上测试您的应用程序并且您将 gps 坐标(纬度,经度)从 DDMS 发送到 AVD 时,真的很难模拟 gps 的真实方面,(因为首先您选择了一些点成为你的 proximPoint,然后你选择离 proximPoint 很远的 anthor 点来查看它是否工作),这不是它在真实设备上所发生的事情。

所以解决方案是在真实设备上测试您的应用程序或使用 DDMS 尝试非常缓慢地更改坐标,直到您处于所需区域。

于 2014-04-12T22:08:37.227 回答