Question

我正在尝试制作后台服务，该服务即使在应用关闭时也会运行，它会获得当前位置，一旦此人接近目的地，应用就会启动。

package als.wakeup;

import com.google.android.gms.maps.model.LatLng;

import android.app.Service;
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.os.IBinder;
import android.util.Log;
import android.widget.Toast;

public class Awake_Alarm extends Service implements LocationListener{
        Location location;
        ConversePrefs cp;
        ConversePrefs_sets cpss;
        LatLng final_dest;
        Settings sets;
        double final_range;
        LocationManager locationManager;
    @Override
    public IBinder onBind(Intent arg0) {

        return null;
    }
    @Override
    public void onCreate() {
        locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
        Criteria criteria = new Criteria();
        final String provider = locationManager.getBestProvider(criteria, true);
        location = locationManager.getLastKnownLocation(provider);
        locationManager.requestLocationUpdates(provider, 20000, 0, this);
        cp = new ConversePrefs(this);
        cpss = new ConversePrefs_sets(this);
        sets = new Settings(this);
        final_range = cp.GetIntSetting("Range", 250);
        final_dest = cp.GetCoords();
        if(cpss.GetIntSetting(sets.def_units_name, 0) == 1){
            final_range = final_range * 1.09361;
        }
        Toast.makeText(getApplicationContext(), "Started", Toast.LENGTH_LONG).show();
        Log.d("STATUS", "RUNNING");
    super.onCreate();
    }


    public double distanceGet(LatLng StartP, LatLng EndP) {
        double lat1 = StartP.latitude;
        double lat2 = EndP.latitude;
        double lon1 = StartP.longitude;
        double lon2 = EndP.longitude;
        double dLat = Math.toRadians(lat2-lat1);
        double dLon = Math.toRadians(lon2-lon1);
        double a = Math.sin(dLat/2) * Math.sin(dLat/2) +
        Math.cos(Math.toRadians(lat1)) * Math.cos(Math.toRadians(lat2)) *
        Math.sin(dLon/2) * Math.sin(dLon/2);
        double c = 2 * Math.asin(Math.sqrt(a));
        return 6366000 * c;
    }

    @Override
    public void onLocationChanged(Location arg0) {
        LatLng me = new LatLng(location.getLatitude(), location.getLongitude());
        double dest = distanceGet(me, final_dest);
        if(dest <= final_range){
        Toast.makeText(getApplicationContext(), String.valueOf(dest)+" Away-.", Toast.LENGTH_LONG).show();
        Log.d("STATUS", "RUNNING-"+String.valueOf(dest));
        }
        Toast.makeText(getApplicationContext(), String.valueOf(dest)+" Away2-.", Toast.LENGTH_LONG).show();
        Log.d("STATUS", "RUNNING2-"+String.valueOf(dest));
    }

    @Override
    public void onProviderDisabled(String arg0) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onProviderEnabled(String arg0) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
        // TODO Auto-generated method stub

    }


}

它似乎工作正常，它启动等运行，当位置更改时，它会根据需要制作Toast文本，但是：到目标的距离不会更新，比如我启动应用，点击启动服务和距离到目的地是1500米，当位置变化时，它仍然会使吐司文字说：“1500米”

我做错了什么？

后台进程有效，但不更新数据？

0 个答案: