定期發送GPS座標

Question

我是一名windows應用程序員，最近開始學習android。我打算在點擊「開始」按鈕後每隔30秒定期發送一個GPS座標的應用程序，並通過點擊「停止」按鈕（我已經開發了一個接受數據的Web服務）停止這樣做。在Windows中，我會使用一個計時器，並在每個「勾號」將找到GPS座標併發送它。請幫助理解如何在android中完成類似的事情。

Answer 1

請檢查我在我的應用程序中的使用方式及其完美。我使用融合api獲取更新位置請按照以下步驟操作。

第1步。這個類 GoogleLocationService.java

public class GoogleLocationService { 
private GoogleServicesCallbacks callbacks = new GoogleServicesCallbacks(); 
LocationUpdateListener locationUpdateListener; 
Context activity; 
protected GoogleApiClient mGoogleApiClient; 
protected LocationRequest mLocationRequest; 

public static final long UPDATE_INTERVAL_IN_MILLISECONDS = 30000; 


public GoogleLocationService(Context activity, LocationUpdateListener locationUpdateListener) { 
    this.locationUpdateListener = locationUpdateListener; 
    this.activity = activity; 
    buildGoogleApiClient(); 
} 

protected synchronized void buildGoogleApiClient() { 
    //Log.i(TAG, "Building GoogleApiClient"); 
    mGoogleApiClient = new GoogleApiClient.Builder(activity) 
      .addConnectionCallbacks(callbacks) 
      .addOnConnectionFailedListener(callbacks) 
      .addApi(LocationServices.API) 
      .build(); 
    createLocationRequest(); 
    mGoogleApiClient.connect(); 
} 

protected void createLocationRequest() { 
    mLocationRequest = new LocationRequest(); 
    mLocationRequest.setInterval(UPDATE_INTERVAL_IN_MILLISECONDS); 
    mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY); 

} 

private class GoogleServicesCallbacks implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener { 

    @Override 
    public void onConnected(Bundle bundle) { 
     startLocationUpdates(); 
    } 

    @Override 
    public void onConnectionSuspended(int i) { 
     mGoogleApiClient.connect(); 
    } 

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

     if (connectionResult.getErrorCode() == ConnectionResult.SERVICE_VERSION_UPDATE_REQUIRED) { 
      Toast.makeText(activity, "Google play service not updated", Toast.LENGTH_LONG).show(); 

     } 
     locationUpdateListener.cannotReceiveLocationUpdates(); 
    } 

    @Override 
    public void onLocationChanged(Location location) { 
     if (location.hasAccuracy()) { 
      if (location.getAccuracy() < 30) { 
       locationUpdateListener.updateLocation(location); 
      } 
     } 
    } 
} 

private static boolean locationEnabled(Context context) { 
    boolean gps_enabled = false; 
    LocationManager lm = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE); 
    try { 
     gps_enabled = lm.isProviderEnabled(LocationManager.GPS_PROVIDER); 
    } catch (Exception ex) { 
     ex.printStackTrace(); 
    } 
    return gps_enabled; 
} 

private boolean servicesConnected(Context context) { 
    return isPackageInstalled(GooglePlayServicesUtil.GOOGLE_PLAY_STORE_PACKAGE, context); 
} 

private boolean isPackageInstalled(String packagename, Context context) { 
    PackageManager pm = context.getPackageManager(); 
    try { 
     pm.getPackageInfo(packagename, PackageManager.GET_ACTIVITIES); 
     return true; 
    } catch (PackageManager.NameNotFoundException e) { 
     e.printStackTrace(); 
     return false; 
    } 
} 


public void startUpdates() { 
    /* 
    * Connect the client. Don't re-start any requests here; instead, wait 
    * for onResume() 
    */ 
    if (servicesConnected(activity)) { 
     if (locationEnabled(activity)) { 
      locationUpdateListener.canReceiveLocationUpdates(); 
      startLocationUpdates(); 
     } else { 
      locationUpdateListener.cannotReceiveLocationUpdates(); 
      Toast.makeText(activity, "Unable to get your location.Please turn on your device Gps", Toast.LENGTH_LONG).show(); 
     } 
    } else { 
     locationUpdateListener.cannotReceiveLocationUpdates(); 
     Toast.makeText(activity, "Google play service not available", Toast.LENGTH_LONG).show(); 
    } 
} 

//stop location updates 
public void stopUpdates() { 
    stopLocationUpdates(); 
} 

//start location updates 
private void startLocationUpdates() { 

    if (checkSelfPermission(activity, ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && checkSelfPermission(activity, ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) { 
     return; 
    } 
    if (mGoogleApiClient.isConnected()) { 
     LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, callbacks); 
    } 
} 

public void stopLocationUpdates() { 
    if (mGoogleApiClient.isConnected()) { 
     LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, callbacks); 
    } 
} 

public void startGoogleApi() { 
    mGoogleApiClient.connect(); 
} 

public void closeGoogleApi() { 
    mGoogleApiClient.disconnect(); 
} 

} 

第二步。使此接口 LocationUpdateListener.java

public interface LocationUpdateListener { 

/** 
* Called immediately the service starts if the service can obtain location 
*/ 
void canReceiveLocationUpdates(); 

/** 
* Called immediately the service tries to start if it cannot obtain location - eg the user has disabled wireless and 
*/ 
void cannotReceiveLocationUpdates(); 

/** 
* Called whenever the location has changed (at least non-trivially) 
* @param location 
*/ 
void updateLocation(Location location); 

/** 
* Called when GoogleLocationServices detects that the device has moved to a new location. 
* @param localityName The name of the locality (somewhere below street but above area). 
*/ 
void updateLocationName(String localityName, Location location); 
} 

步驟3.調用此對您的OnCreate

私人GoogleLocationService googleLocationService;

googleLocationService = new GoogleLocationService(context, new LocationUpdateListener() { 
    @Override 
    public void canReceiveLocationUpdates() { 
    } 

    @Override 
    public void cannotReceiveLocationUpdates() { 
    } 

    //update location to our servers for tracking purpose 
    @Override 
    public void updateLocation(Location location) { 
     if (location != null) { 
      Timber.e("updated location %1$s %2$s", location.getLatitude(), location.getLongitude()); 

     } 
    } 

    @Override 
    public void updateLocationName(String localityName, Location location) { 

     googleLocationService.stopLocationUpdates(); 
    } 
}); 
googleLocationService.startUpdates(); 


and call this onDestroy 
if (googleLocationService != null) { 
    googleLocationService.stopLocationUpdates(); 
} 

希望這會幫助你解決你的問題。

Answer 2

看一看RxGpsService（使用RxJava檢索GPS位置和路由統計信息的Android服務）。它檢索一個包含當前速度，距離，時間和航點的RouteStats對象。當您停止計時時，您也可以播放/停止計時器以放棄位置。