android - 将 Gps 作为后台服务运行并将接收到的当前位置数据与 Sqlite 中的值进行比较？

Question

我知道有很多关于此的问题，几天来我一直在研究所有这些问题，但找不到合理的答案。我是 android 的新手，所以我不知道事情是如何完成的.

基本上我想知道如何在后台将 GPS 作为服务运行，例如当应用程序安装后它会启动，以及如何将从 gps 后台服务接收的数据与 SQLite 数据库中的数据进行比较。

Answer 1

您可以像上面那样提供服务，该服务从 GPS 和网络提供商获取位置信息，并在后台插入数据库。

package com.example.alireza.locationtracker;
import android.Manifest;
import android.app.Service;
import android.content.Intent;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.os.CountDownTimer;
import android.os.IBinder;
import android.util.Log;

import com.android.volley.AuthFailureError;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;

import java.util.Hashtable;
import java.util.Map;


public class LocationTracker extends Service {

public static LocationListener gpsloclistener;
public static LocationListener netlistener;
public static LocationManager mLocationManager;
public static Location gpsLOc;
public static Location netLOc;
private static Location gpslocation;
private static Location netlocation;
public static boolean isGPSEnabled;
public static boolean isNetworkEnabled;


@Override
public void onCreate() {
    super.onCreate();
    gpsloclistener = new gpsloclistener();
    netlistener = new netlistener();
    getLocation();
   // myfunc();

}

@Override
public IBinder onBind(Intent intent) {

    return null;
}


public void getLocation() {
    try
    {
        mLocationManager = (LocationManager) this.getSystemService(LOCATION_SERVICE);
        isGPSEnabled = mLocationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
        isNetworkEnabled = mLocationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
        if (isGPSEnabled || isNetworkEnabled)
        {
            if (isGPSEnabled)
            {
                mLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,180000,0,gpsloclistener);
            }
            if (isNetworkEnabled)
            {
                mLocationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 10000, 0, netlistener);//aslan bar roye network nemishe mahdodiyat gozasht
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
}

public class gpsloclistener implements LocationListener {
    @Override
    public void onLocationChanged(final Location location) {
        if (location.getAccuracy() < 20) {
                G.database.execSQL("INSERT INTO Gps_Location (Gps_lat,Gps_long,Gps_speed,Gps_time,Gps_bearing,Gps_alt,Gps_acur) VALUES ('" + location.getLatitude() + "','" + location.getLongitude() + "','" + location.getSpeed() + "','" + System.currentTimeMillis() + "','" + location.getBearing() + "','" + location.getAltitude() + "','" + location.getAccuracy() + "')");


    }

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {

    }

    @Override
    public void onProviderEnabled(String provider) {
        getLocation();
    }

    @Override
    public void onProviderDisabled(String provider) {

    }
}

private class netlistener implements LocationListener {
    @Override
    public void onLocationChanged(final Location location) {
            G.database.execSQL("INSERT INTO Net_Location (Net_lat,Net_long,Net_speed,Net_time,Net_bearing,Net_alt,Net_acur) VALUES ('" + location.getLatitude() + "','" + location.getLongitude() + "','" + location.getSpeed() + "','" + System.currentTimeMillis() + "','" + location.getBearing() + "','" + location.getAltitude() + "','" + location.getAccuracy() + "')");

    }

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {

    }

    @Override
    public void onProviderEnabled(String provider) {
        getLocation();
    }

    @Override
    public void onProviderDisabled(String provider) {

    }
}

此服务插入位置到 SQL lite 数据库，您必须从 Main Activity 之类的地方启动此服务

        try{
        startService(new Intent(getBaseContext(), LocationTracker.class));
    }catch (Exception ex){
    }

并与 SQL lite 位置进行比较，这很有趣，计算点之间的距离

    public static double distFrom(double lat1, double lng1, double lat2, double lng2) {
    double earthRadius = 3958.75;
    double dLat = Math.toRadians(lat2 - lat1);
    double dLng = Math.toRadians(lng2 - lng1);
    double a = Math.sin(dLat / 2) * Math.sin(dLat / 2) +
            Math.cos(Math.toRadians(lat1)) * Math.cos(Math.toRadians(lat2)) *
                    Math.sin(dLng / 2) * Math.sin(dLng / 2);
    double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
    double dist = earthRadius * c;

    int meterConversion = 1609;
    double v = dist * meterConversion;
    return v;
}

最后定义要显示的服务

  <service android:name=".LocationTracker"/>