如何使用 android 应用程序在后台跟踪位置？

Question

Im a complete beginner in this and using android studio to make a GPS tracking app for a project. I need the app to be able to track the user's location even when the app is closed. Something like how the Uber app tracks your location even if the app isn't open. How do i do something like that?

Answer 1

ADD THIS IN YOUR MANIFEST:

   <uses-permission android:name="android.permission.INTERNET"></uses-permission>
   <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"></uses-permission>
   <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"></uses-permission>

Declare service in the manifest

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

In your activity do following steps

   private static final int REQUEST_PERMISSIONS = 100;
   Double latitude,longitude;
   Geocoder geocoder;
   boolean isPermissionAllowed;

Oncreate:

    geocoder = new Geocoder(this, Locale.getDefault());
    Location_permission();

   if (isPermissionAllowed) {
    Intent intent = new Intent(getApplicationContext(), LocationService.class);
    startService(intent);
    }


  private void Location_permission() {
    if ((ContextCompat.checkSelfPermission(getApplicationContext(), android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED)) {

        if ((ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this, android.Manifest.permission.ACCESS_FINE_LOCATION))) {


        } else {
            ActivityCompat.requestPermissions(MainActivity.this, new String[]{android.Manifest.permission.ACCESS_FINE_LOCATION

                    },
                    REQUEST_PERMISSIONS);

        }
    } else {
        isPermissionAllowed = true;
    }
}

 @Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);

    switch (requestCode) {
        case REQUEST_PERMISSIONS: {
            if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                isPermissionAllowed = true;

            } else {
                Toast.makeText(getApplicationContext(), "Please allow the permission", Toast.LENGTH_LONG).show();

            }
        }
    }
}

LocationService.java

  public class LocationService extends Service implements LocationListener{

boolean isGPSEnable = false;
boolean isNetworkEnable = false;
double latitude,longitude;
LocationManager locationManager;
Location location;
private Handler mHandler = new Handler();
private Timer mTimer = null;
long notify_interval = 1000;
public static String str_receiver = "servicetutorial.service.receiver";
Intent intent;




public LocationService() {

}

@Nullable
@Override
public IBinder onBind(Intent intent) {
    return null;
}

@Override
public void onCreate() {
    super.onCreate();

    mTimer = new Timer();
    mTimer.schedule(new TimerTaskToGetLocation(),5,notify_interval);
    intent = new Intent(str_receiver);
}

@Override
public void onLocationChanged(Location location) {
 **//you can get updated location here**
}

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

}

@Override
public void onProviderEnabled(String provider) {

}

@Override
public void onProviderDisabled(String provider) {

}

private void fn_getlocation(){
    locationManager = (LocationManager)getApplicationContext().getSystemService(LOCATION_SERVICE);
    isGPSEnable = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
    isNetworkEnable = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);

    if (!isGPSEnable && !isNetworkEnable){

    }else {

        if (isNetworkEnable){
            location = null;
            locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER,1000,0,this);
            if (locationManager!=null){
                location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
                if (location!=null){

                    Log.e("latitude",location.getLatitude()+"");
                    Log.e("longitude",location.getLongitude()+"");

                    latitude = location.getLatitude();
                    longitude = location.getLongitude();
                    fn_update(location);
                }
            }

        }


        if (isGPSEnable){
            location = null;
            locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,1000,0,this);
            if (locationManager!=null){
                location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
                if (location!=null){
                    Log.e("latitude",location.getLatitude()+"");
                    Log.e("longitude",location.getLongitude()+"");
                    latitude = location.getLatitude();
                    longitude = location.getLongitude();
                    fn_update(location);
                }
            }
        }


    }

}

private class TimerTaskToGetLocation extends TimerTask{
    @Override
    public void run() {

        mHandler.post(new Runnable() {
            @Override
            public void run() {
                fn_getlocation();
            }
        });

    }
}

private void fn_update(Location location){

    intent.putExtra("latutide",location.getLatitude()+"");
    intent.putExtra("longitude",location.getLongitude()+"");
    sendBroadcast(intent);
}

}