如何在android上始終保持GPS /定位服務？

Question

如何在android上始終保持GPS /位置服務？

如果有代碼可以在Playstore上實現這個或任何可用的應用程序？

我需要跟蹤我的員工，當他們在交付路線。

Answer 1

我之前做過類似的事情。 這裏是位置服務：

public class LocationService extends Service { 
    public static final String BROADCAST_ACTION = "Hello World"; 
    private static final int TWO_MINUTES = 1000 * 60 * 2; 
    public LocationManager locationManager; 
    public MyLocationListener listener; 
    public Location previousBestLocation = null; 

    public long refreshTime = 60*1000; 

    Intent intent; 
    int counter = 0; 

    @Override 
    public void onCreate() { 
     super.onCreate(); 
     intent = new Intent(BROADCAST_ACTION); 
    } 

    @Override 
    public int onStartCommand(Intent intent, int flags, int startId) { 
     locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); 
     listener = new MyLocationListener(); 
     if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, 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 START_STICKY; 
     } 
     locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, refreshTime, 100, listener); 
     locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, refreshTime, 100, listener); 

     return START_STICKY; 
    } 
// @Override 
// public void onStart(Intent intent, int startId) { 
//  } 

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

    protected boolean isBetterLocation(Location location, Location currentBestLocation) { 
     if (currentBestLocation == null) { 
      // A new location is always better than no location 
      return true; 
     } 

     // Check whether the new location fix is newer or older 
     long timeDelta = location.getTime() - currentBestLocation.getTime(); 
     boolean isSignificantlyNewer = timeDelta > TWO_MINUTES; 
     boolean isSignificantlyOlder = timeDelta < -TWO_MINUTES; 
     boolean isNewer = timeDelta > 0; 

     // If it's been more than two minutes since the current location, use the new location 
     // because the user has likely moved 
     if (isSignificantlyNewer) { 
      return true; 
      // If the new location is more than two minutes older, it must be worse 
     } else if (isSignificantlyOlder) { 
      return false; 
     } 

     // Check whether the new location fix is more or less accurate 
     int accuracyDelta = (int) (location.getAccuracy() - currentBestLocation.getAccuracy()); 
     boolean isLessAccurate = accuracyDelta > 0; 
     boolean isMoreAccurate = accuracyDelta < 0; 
     boolean isSignificantlyLessAccurate = accuracyDelta > 200; 

     // Check if the old and new location are from the same provider 
     boolean isFromSameProvider = isSameProvider(location.getProvider(), 
       currentBestLocation.getProvider()); 

     // Determine location quality using a combination of timeliness and accuracy 
     if (isMoreAccurate) { 
      return true; 
     } else if (isNewer && !isLessAccurate) { 
      return true; 
     } else if (isNewer && !isSignificantlyLessAccurate && isFromSameProvider) { 
      return true; 
     } 
     return false; 
    } 


    /** Checks whether two providers are the same */ 
    private boolean isSameProvider(String provider1, String provider2) { 
     if (provider1 == null) { 
      return provider2 == null; 
     } 
     return provider1.equals(provider2); 
    } 


    @Override 
    public void onDestroy() { 
     // handler.removeCallbacks(sendUpdatesToUI); 
     super.onDestroy(); 
     Log.i("STOP_SERVICE", "DONE"); 
     if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, 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; 
     } 
     locationManager.removeUpdates(listener); 
    } 

    public static Thread performOnBackgroundThread(final Runnable runnable) { 
     final Thread t = new Thread() { 
      @Override 
      public void run() { 
       try { 
        runnable.run(); 
       } finally { 

       } 
      } 
     }; 
     t.start(); 
     return t; 
    } 

    public class MyLocationListener implements LocationListener 
    { 

     public void onLocationChanged(final Location loc) 
     { 
      Log.i("**************************************", "Location changed"); 
      if(isBetterLocation(loc, previousBestLocation)) { 
       loc.getLatitude(); 
       loc.getLongitude(); 
       intent.putExtra("Latitude", loc.getLatitude()); 
       intent.putExtra("Longitude", loc.getLongitude()); 
       intent.putExtra("Provider", loc.getProvider()); 
       sendBroadcast(intent); 
       LocationHelper.sendLocation(loc.getLatitude(), loc.getLongitude(), 
       new MyPreferenceManager(App.context).getAuthToken()); 
       Log.i("b8", "Location : "+ loc.getLatitude() + ":"+ loc.getLongitude()); 
      } 
     } 

     public void onProviderDisabled(String provider) 
     { 
      MyToast.makeText(getApplicationContext(), "Gps Disabled", Toast.LENGTH_SHORT).show(); 
     } 


     public void onProviderEnabled(String provider) 
     { 
      MyToast.makeText(getApplicationContext(), "Gps Enabled", Toast.LENGTH_SHORT).show(); 
     } 


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

     } 

    } 
} 

，你需要在你應該知道清單

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

另一件事添加此權限是每當認爲沒有足夠的內存是GC可以殺死服務（而應用程序在後臺或由用戶關閉） 當然使用return START_STICKY;在onStartCommand方法導致重新啓動服務，但它將取決於空閒內存