Question

我是android的新手。现在我正在开发一个基于位置的闹钟。但是在这个我需要在用户移动时持续经历纬度和经度，并且应用程序将处于关闭模式。我有很多代码但是当应用程序打开时，所有这些都有效。我给出了下面的代码。

服务类

public class LocationLoggerService 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;

    Intent intent;
    int counter = 0;

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

    @Override
    public void onStart(Intent intent, int startId) {      
        locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        listener = new MyLocationListener();        
        locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, listener);
        locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, listener);
    }

    @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.v("STOP_SERVICE", "DONE");
        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());      
                System.out.println("location"+loc.getLatitude());
                sendBroadcast(intent);          
                /*final Geocoder geocoder = new Geocoder(getApplicationContext(), Locale.getDefault());         
                String Text = "";
                try {
                    List<Address> addresses = geocoder.getFromLocation(loc.getLatitude(), loc.getLongitude(), 1);                
                    Text = "My current location is: "+addresses.get(0).getAddressLine(0); 

                } catch (Exception e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                    Text = "My current location is: " +"Latitude = " + loc.getLatitude() + ", Longitude = " + loc.getLongitude();  
                }
                */
                //Toast.makeText( getApplicationContext(), "Location polled to server", Toast.LENGTH_SHORT).show();
            }                               
        }

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


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


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

        }

    }
    }

活动代码

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ComponentName comp = new ComponentName(getPackageName(), LocationLoggerService.class.getName());
        ComponentName service = startService(new Intent().setComponent(comp));
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

}

Answer 1

在Service类中添加onStartCommand方法

@Override
public int onStartCommand(Intent intent, int flags, int startId) {

    Log.i(TAG, "Service onStartCommand");

     }
     return Service.START_STICKY;
}

此处返回的是 Service.START_STICKY

即使您从最近杀死并且app未在前台运行，它也会启动服务。

此处有关于Service.START_STICKY和START_NON_STICKY的更多explanation

在应用关闭时查找经度和纬度

服务类

1 个答案: