android - 使用网络和 gps 卫星 Android 的最简单方法

Question

我需要监控用户的位置以获得纬度和经度，当我使用网络提供商或 gps 提供商时，它工作正常。但是当我使用这两个提供商时，我没有得到值(value)。任何人都请提供解决方案。正在搜索并尝试很多示例

   // Get the location manager
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
// Define the criteria how to select the locatioin provider -> use
// default
Criteria criteria = new Criteria();
provider = locationManager.getBestProvider(criteria, true);
networkLoc = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
gpsLoc = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);

  if (networkLoc != null) {
     System.out.println("Provider " + provider + " has been selected.");
  double l = (double) (networkLoc.getLatitude());
  double lng11 = (double) (networkLoc.getLongitude());
     latituteField1.setText(Double.toString(l));
  longitudeField1.setText(Double.toString(lng11));
   } 
  if ( gpsLoc  != null) {
    System.out.println("Provider " + provider + " has been selected.");
  double l0t = (double) (gpsLoc.getLatitude());
 double l0g = (double) (gpsLoc.getLongitude());
   latituteField.setText(Double.toString(l0t));
 longitudeField.setText(Double.toString(l0g));

 }
   locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, this);
   locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this);

     }
 @Override
 protected void onResume() {
super.onResume();

locationManager.requestLocationUpdates(
        LocationManager.NETWORK_PROVIDER, 
        MINIMUM_TIME_BETWEEN_UPDATES, 
        MINIMUM_DISTANCE_CHANGE_FOR_UPDATES,
         this
 );  }
  /* Remove the locationlistener updates when Activity is paused */
    @Override
protected void onPause() {
super.onPause();
locationManager.requestLocationUpdates(
        LocationManager.NETWORK_PROVIDER, 
        MINIMUM_TIME_BETWEEN_UPDATES, 
        MINIMUM_DISTANCE_CHANGE_FOR_UPDATES,
        this
);
}

      @Override
  public void onLocationChanged(Location location) {
lat1 = (double) (networkLoc.getLatitude());
lng1 = (double) (networkLoc.getLongitude());
latituteField1.setText(Double.toString(lat1));
 longitudeField1.setText(Double.toString(lng1));      
 lat = (double) (gpsLoc.getLatitude());
lng = (double) (gpsLoc.getLongitude());
 latituteField.setText(Double.toString(lat));
 longitudeField.setText(Double.toString(lng));  
  }
 @Override
      public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub

  }

     @Override
  public void onProviderEnabled(String provider) {
Toast.makeText(this, "Enabled new provider " + provider,
        Toast.LENGTH_SHORT).show();

     }

    @Override
    public void onProviderDisabled(String provider) {
Toast.makeText(this, "Disenabled provider " + provider,
        Toast.LENGTH_SHORT).show();
 }

  protected void Display(Cursor c) {
Toast.makeText(this, "rowid: " + c.getString(0) + "\n" +
 "Latitude: " + c.getString(1) + "\n" + "Longitude: " + c.getString(2) + "\n" +
 Toast.LENGTH_LONG, 0).show();
     }

Answer 1

不要向多个供应商请求位置更新。相反，选择 Criteria Android 会选择最适合您的。

例如代替:

   locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, this);
   locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this);

使用:

   Criteria c = new Criteria();
   c.setAccuracy(Criteria.ACCURACY_COARSE); //Or whatever criteria you want
   final String PROVIDER = locationManager.getBestProvider(c, true);
   locationManager.requestLocationUpdates(PROVIDER, minTime, minDistance, this);