没有从后台服务获取纬度和经度

Posted 2023-04-14

【中文标题】没有从后台服务获取纬度和经度

【英文标题】：Not getting latitude and longitude from background service

【发布时间】：2017-03-26 01:37:46

【问题描述】：

我是 android 新手，我想在后台运行一项服务，并在 10 分钟后获取纬度和经度或地理地址并发送到服务器。

请帮帮我。

这是我的代码：

活动中

public void serviceCall()
  Log.e("INSIDE ALARM", "INSIDE ALARM");
  Intent intent = new Intent(getApplicationContext(), MyService.class);
  final PendingIntent pIntent = PendingIntent.getBroadcast(this, MyService.REQUEST_CODE,
                intent, PendingIntent.FLAG_UPDATE_CURRENT);
  long firstMillis = System.currentTimeMillis();
  AlarmManager alarm = (AlarmManager) this.getSystemService(Context.ALARM_SERVICE);
  alarm.setInexactRepeating(AlarmManager.RTC_WAKEUP, firstMillis,
                6000, pIntent);

在 Reciver 中

public static final int REQUEST_CODE = 9411;

@Override
public void onReceive(Context context, Intent intent) 
  Intent inti = new Intent(context, LocationService.class);
  intent1.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK |Intent.FLAG_ACTIVITY_CLEAR_TOP |Intent.FLAG_ACTIVITY_NEW_TASK);
  context.startService(inti);

在 IntentService 中

protected void onHandleIntent(Intent intent) 
  Log.e("imsidehandler Service", ":=");
  mRequestingLocationUpdates = false;
  buildGoogleApiClient();
  createLocationRequest();
  buildLocationSettingsRequest();
  checkLocationSettings();
  sendDataServer();


public void onConnected(Bundle bundle) 
  if (mCurrentLocation == null) 
     mCurrentLocation = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
     mLastUpdateTime = DateFormat.getTimeInstance().format(new Date());
     updateLocationUI();
  


public void onConnectionSuspended(int i) 



public void onLocationChanged(Location location) 
  mCurrentLocation = location;
  mLastUpdateTime = DateFormat.getTimeInstance().format(new Date());


public void onConnectionFailed(ConnectionResult connectionResult) 



private synchronized void buildGoogleApiClient() 
  mGoogleApiClient = new GoogleApiClient.Builder(this)
            .addConnectionCallbacks(this)
            .addOnConnectionFailedListener(this)
            .addApi(LocationServices.API)
            .build();


private void createLocationRequest() 
  mLocationRequest = new LocationRequest();
  mLocationRequest.setInterval(UPDATE_INTERVAL_IN_MILLISECONDS);
  mLocationRequest.setFastestInterval(FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS);
  mLocationRequest.setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY);


private void buildLocationSettingsRequest() 
  LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder();
  builder.addLocationRequest(mLocationRequest);
  mLocationSettingsRequest = builder.build();


private void checkLocationSettings() 
  PendingResult<LocationSettingsResult> result =
            LocationServices.SettingsApi.checkLocationSettings(
                    mGoogleApiClient,
                    mLocationSettingsRequest
            );
  result.setResultCallback(this);


protected boolean 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) 
        return true;
  

  return false;


protected void stopLocationUpdates() 
    LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, (com.google.android.gms.location.LocationListener) this).setResultCallback(new ResultCallback<Status>() 
        @Override
        public void onResult(Status status) 
            mRequestingLocationUpdates = false;
        
    );


private void updateLocationUI() 
  if (mCurrentLocation != null) 
    updateCityAndPincode(mCurrentLocation.getLatitude(), mCurrentLocation.getLongitude());

  


private void updateCityAndPincode(double latitude, double longitude) 
  try 
     Log.e("latitude","==>"+longitude);
     Log.e("longitude","==>"+longitude);
     this.latitude = latitude;
     this.longitude = longitude;
     getGeoAddress(latitude, longitude);
   catch (Exception e) 
  



private void getGeoAddress(Double latitude, Double longitude) 
  Geocoder geocoder = new Geocoder(this, Locale.getDefault());
  String result = null;
  List<Address> addressList = null;
  try 
     addressList = geocoder.getFromLocation(
                latitude, longitude, 1);

      if (addressList != null && addressList.size() > 0) 
         Address address = addressList.get(0);
         Log.e("address","==>"+address);
         for (int i = 0; i < address.getMaxAddressLineIndex(); i++) 
            result += address.getAddressLine(i);
            result += " ";
         
         if (result.contains("null")) 
            result1 = result.replace("null", "");
         
       
     catch (IOException e) 
        e.printStackTrace();
    
  

  public void onResult(LocationSettingsResult locationSettingsResult) 
    final Status status = locationSettingsResult.getStatus();
    switch (status.getStatusCode()) 
        case LocationSettingsStatusCodes.SUCCESS:

            startLocationUpdates();

            break;
        case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
            try 
                status.startResolutionForResult((Activity) getApplicationContext(), REQUEST_CHECK_SETTINGS);
             catch (IntentSender.SendIntentException e) 
            
            break;
        case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
            break;

    

请帮帮我

【问题讨论】：

具体的问题是什么？ Service 不是基于基于 AlarmManager 的定时器机制运行的吗？还是它运行了，但您只是没有收到有效的位置？

【参考方案1】：

getLastLocation() 方法只是获取设备碰巧知道的最后一个已知位置。有时设备不会“碰巧知道”它的位置并返回null。

设备不会自行确定其位置，而是仅在某些应用程序请求位置时确定。因此，您的应用现在依赖于请求位置更新的其他应用。

这里的“最后已知位置”也意味着：它可能不是最新的。位置确实带有时间戳，可用于评估该位置是否仍然相关。

我在您的代码中的任何地方都没有看到对requestLocationUpdates() 的调用。这将按照您可以指定的时间间隔请求最新的位置更新。

您的onConnected() 方法可能有：

public void onConnected(Bundle bundle)     
    LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this);

（可以删除getLastLocation()调用。）

您的IntentService 可以实现LocationListener 并执行与onConnected() 现在相同的操作，但只有在位置更新到达之后：

@Override
public void onLocationChanged(Location location) 
    // Cancel the updates after the first one:
    LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this);

    mCurrentLocation = location;
    mLastUpdateTime = DateFormat.getTimeInstance().format(new Date());
    updateLocationUI();

这将是通过最小的代码更改请求和处理位置更新的方式。

当然还有其他方法，例如每 10 分钟请求一次更新并通过PendingIntent 处理它们。有this version of requestLocationUpdates() 需要PendingIntent：

public abstract PendingResult<Status> requestLocationUpdates (GoogleApiClient client, LocationRequest request, PendingIntent callbackIntent)

这将取代您当前的计时器机制。