计算 onLocationChanged 方法之间的时间

Posted 2023-04-14

【中文标题】计算 onLocationChanged 方法之间的时间

【英文标题】：Calculate time between onLocationChanged method

【发布时间】：2017-08-24 22:13:21

【问题描述】：

我需要计算每次位置变化（onLocationChanged）之间的时间差。这样做的正确方法是什么？

我获取用户位置的代码：

public class LocationService extends Service implements
    GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener 

private Looper mServiceLooper;
private ServiceHandler mServiceHandler;
private GoogleApiClient mGoogleApiClient;
private LocationRequest mLocationRequest;
private DatabaseHelpers mDatabaseHelpers;

private final class ServiceHandler extends Handler 
    public ServiceHandler(Looper looper) 
        super(looper);
    


@Override
public void onCreate() 
    HandlerThread thread = new HandlerThread("ServiceStartArguments",
            Process.THREAD_PRIORITY_BACKGROUND);
    thread.start();

    // Get the HandlerThread's Looper and use it for our Handler
    mServiceLooper = thread.getLooper();
    mServiceHandler = new ServiceHandler(mServiceLooper);
    mDatabaseHelpers = new DatabaseHelpers(LocationService.this);


public void buildGoogleApiClient() 
    createLocationRequest();
    if (mGoogleApiClient == null) 
        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .addApi(LocationServices.API)
                .build();
        mGoogleApiClient.connect();
    


protected void createLocationRequest() 
    mLocationRequest = new LocationRequest();
    mLocationRequest.setInterval(10000);
    mLocationRequest.setFastestInterval(5000);
    mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);


private String getCurrentTimeStamp() 
    SimpleDateFormat simpleDateFormat = new SimpleDateFormat("dd-MM-yyyy-HH-mm");
    String format = simpleDateFormat.format(new Date());
    return format;


public void startLocationUpdates() 
    if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) 
        // TODO: Consider calling
        //    ActivityCompat#requestPermissions
        // here to request the missing permissions, and then overriding
        //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
        //                                          int[] grantResults)
        // to handle the case where the user grants the permission. See the documentation
        // for ActivityCompat#requestPermissions for more details.
        return;
    
    LocationServices.FusedLocationApi.requestLocationUpdates(
            mGoogleApiClient, mLocationRequest, this);


protected void stopLocationUpdates() 
    LocationServices.FusedLocationApi.removeLocationUpdates(
            mGoogleApiClient, this);
    mGoogleApiClient.disconnect();


@Override
public int onStartCommand(Intent intent, int flags, int startId) 
    Log.i("Location Service", "Started");
    buildGoogleApiClient();
    return START_STICKY;


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


@Override
public void onDestroy() 
    // The service is no longer used and is being destroyed
    stopLocationUpdates();


@Override
public void onLocationChanged(Location location) 

@Override
public void onConnected(@Nullable Bundle bundle) 
    startLocationUpdates();


@Override
public void onConnectionSuspended(int i) 


@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) 

在上面的代码中，我可以很好地获取用户的位置，但我需要计算调用 onLocationChanged 方法时的时间差。

【参考方案1】：

正确的方法？只需使用 Location 对象的getTime() 方法即可。

比较新的和以前的位置，然后找出差异。

private Location mPrevLocation;

@Override
public void onLocationChanged(Location location) 
    if(mPrevLocation != null)
        long prevTime = mPrevLocation.getTime();
        long currentTime = location.getTime();

        // This is exactly what you want 
        long diffTime = currentTime - prevTime ;
     

    mPrevLocation = location;