如何在应用程序未打开时将位置更新到服务器

Question

当用户从一个地方旅行到另一个地方时，我需要更新服务器的位置。我们可以在我的应用程序打开时更新。如果用户长时间没有打开app，如何更新位置？

Answer 1

使用服务。

public class MyService extends Service implements LocationListener,
    GoogleApiClient.ConnectionCallbacks,
    GoogleApiClient.OnConnectionFailedListener {
private static final String TAG = "MyService";
private static final int UPDATE_INTERVAL = 5000;
private static final int FASTEST_INTERVAL = 3000;
private GoogleApiClient client;
private LocationRequest locationRequest;
private String lat, lon;

@Override
public void onConnected(@Nullable Bundle bundle) {
    if (Build.VERSION.SDK_INT>Build.VERSION_CODES.LOLLIPOP_MR1) {
    if (ActivityCompat.checkSelfPermission(this, 
Manifest.permission.ACCESS_FINE_LOCATION) == 
PackageManager.PERMISSION_GRANTED && 
ActivityCompat.checkSelfPermission(this, 
Manifest.permission.ACCESS_COARSE_LOCATION) == 
PackageManager.PERMISSION_GRANTED) {
            LocationServices.FusedLocationApi.requestLocationUpdates(client, 
locationRequest, this);
        }
    }else {
        LocationServices.FusedLocationApi.requestLocationUpdates(client, 
locationRequest, this);
    }
}

@Override
public void onConnectionSuspended(int i) {

}

@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {

}

@Override
public void onLocationChanged(Location location) {
    Log.i(TAG, "onLocationChanged: " + location);
    lat = String.valueOf(location.getLatitude());
    lon = String.valueOf(location.getLongitude());

    updateLocation();

}


@Override
public IBinder onBind(Intent arg0) {
    return null;
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    Log.d(TAG, "onStartCommand");
    super.onStartCommand(intent, flags, startId);
    return START_STICKY;
}

@Override
public void onCreate() {
    Log.d(TAG, "onCreate");
    preferences = getSharedPreferences(AppConfig.PREF, MODE_PRIVATE);
    locationRequest = new LocationRequest();
    locationRequest.setInterval(UPDATE_INTERVAL);
    locationRequest.setFastestInterval(FASTEST_INTERVAL);
    locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);

    buildGoogleApiClient();


}

protected synchronized void buildGoogleApiClient() {
    client = new GoogleApiClient.Builder(this)
            .addConnectionCallbacks(this)
            .addOnConnectionFailedListener(this)
            .addApi(LocationServices.API)
            .build();
    client.connect();
}

@Override
public void onDestroy()    //remove location update
{
    Log.d(TAG, "onDestroy");
    super.onDestroy();

    if (client != null) {
        LocationServices.FusedLocationApi.removeLocationUpdates(client, this);
        client.disconnect();
    }


}


private void updateLocation(){

    StringRequest stringRequest = new StringRequest(Request.Method.POST, AppConfig.URL_LOCATIONUPDATE, new Response.Listener<String>() {
        @Override
        public void onResponse(String response) {
            Toast.makeText(getApplicationContext(), response, Toast.LENGTH_LONG).show();

    }, new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            Toast.makeText(getApplicationContext(), error.toString(), Toast.LENGTH_LONG).show();
        }
    }) {
        protected Map<String, String> getParams() {
            Map<String, String> params = new HashMap<>();
            params.put("currLat",lat );
            params.put("currLon",lon );
            return params;
        }
    };
    RequestQueue requestQueue = Volley.newRequestQueue(getApplicationContext());
    requestQueue.add(stringRequest);
}
}

从您的活动中调用此服务。

Intent serviceIntent = new Intent(this, MyService.class);
startService(serviceIntent);