不知道在某些Android手機中的準確位置

Question

我已經使用了下面的代碼。它工作正常，但在某些設備，如Redme，華碩沒有得到準確的位置。它顯示我離我目前的位置距離20公里遠。apotx沒有得到問題的人有什麼想法，請分享想法。提前感謝。

public class Currentlocation extends Service implements LocationListener { 

private final Context mContext; 

// flag for GPS status 
boolean isGPSEnabled = false; 

// flag for network status 
boolean isNetworkEnabled = false; 

// flag for GPS status 
public boolean canGetLocation = false; 

Location location; // location 
double latitude; // latitude 
double longitude; // longitude 

// The minimum distance to change Updates in meters 
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 10; // 10 meters 

// The minimum time between updates in milliseconds 
private static final long MIN_TIME_BW_UPDATES = 1000 * 60 * 1; // 1 minute 

// Declaring a Location Manager 
protected LocationManager locationManager; 

SetOnLocationFoundListner OLF; 

public interface SetOnLocationFoundListner { 
    public void onLocationFound(Location location, boolean getLocRegularly, GoogleMap gmap); 
} 

public Currentlocation(Context context) { 
    this.mContext = context; 
    getLocation(); 
} 

public Location getLocation() { 
    try { 
     locationManager = (LocationManager) mContext.getSystemService(LOCATION_SERVICE); 

     // getting GPS status 
     isGPSEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER); 

     // getting network status 
     isNetworkEnabled = locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER); 

     if (!isGPSEnabled && !isNetworkEnabled) { 
      // no network provider is enabled 
     } else { 
      this.canGetLocation = true; 
      // First get location from Network Provider 
      if (isNetworkEnabled) { 
       locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, MIN_TIME_BW_UPDATES, 
         MIN_DISTANCE_CHANGE_FOR_UPDATES, this); 
       Log.d("Network", "Network"); 
       if (locationManager != null) { 
        location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER); 
        if (location != null) { 
         latitude = location.getLatitude(); 
         longitude = location.getLongitude(); 
        } 
       } 
      } 
      // if GPS Enabled get lat/long using GPS Services 
      if (isGPSEnabled) { 
       if (location == null) { 
        locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, MIN_TIME_BW_UPDATES, 
          MIN_DISTANCE_CHANGE_FOR_UPDATES, this); 
        Log.d("GPS Enabled", "GPS Enabled"); 
        if (locationManager != null) { 
         location = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER); 
         if (location != null) { 
          latitude = location.getLatitude(); 
          longitude = location.getLongitude(); 
         } 
        } 
       } 
      } 
     } 

    } catch (Exception e) { 
     e.printStackTrace(); 
    } 

    return location; 
} 

/** 
* Stop using GPS listener Calling this function will stop using GPS in your 
* app 
*/ 
public void stopUsingGPS() { 
    if (locationManager != null) { 
     locationManager.removeUpdates(Currentlocation.this); 
    } 
} 

/** 
* Function to get latitude 
*/ 
public double getLatitude() { 
    if (location != null) { 
     latitude = location.getLatitude(); 
    } 

    // return latitude 
    return latitude; 
} 

/** 
* Function to get longitude 
*/ 
public double getLongitude() { 
    if (location != null) { 
     longitude = location.getLongitude(); 
    } 

    // return longitude 
    return longitude; 
} 

/** 
* Function to check GPS/wifi enabled 
* 
* @return boolean 
*/ 
public boolean canGetLocation() { 
    return this.canGetLocation; 
} 

@Override 
public void onLocationChanged(Location location) { 
    // TODO Auto-generated method stub 

} 

@Override 
public void onStatusChanged(String provider, int status, Bundle extras) { 
    // TODO Auto-generated method stub 

} 

@Override 
public void onProviderEnabled(String provider) { 
    // TODO Auto-generated method stub 

} 

@Override 
public void onProviderDisabled(String provider) { 
    // TODO Auto-generated method stub 

} 

@Override 
public IBinder onBind(Intent intent) { 
    // TODO Auto-generated method stub 
    return null; 
} 

/** 
* Function to show settings alert dialog On pressing Settings button will 
* lauch Settings Options 
*/ 

} 

Answer 1

你不能指望電話既不總是有一個有效的「最後已知的位置」，也不能以微秒定義它的位置。

您首先撥打requestLocationUpdates()，然後立即撥打getLastKnownLocation()。沒有時間讓手機確定/更新「最後的已知位置」。除此之外，當您致電getLocation()時，您總是一次又一次致電requestLocationUpdates()。當你想開始接收位置更新時，只需調用一次即可。

只需訂閱接收位置更新一次，並始終獲取回調中發生的最新位置，並且延遲時間很短。您已經有了空的onLocationChanged()方法。這是回調方法。只要做到這一點來處理位置更新。

如果您不想收到任何進一步的更新，您一旦收到onLocationChanged()回撥中的新鮮和最新位置，當然可以致電removeUpdates()或removeLocationUpdates()。

一些有用的討論＃1：

How to get location that isn't out of date?

Android: getLastKnownLocation out-of-date - how to force location refresh?

Android - Reliably getting the current location