Question

我已经查看过，找不到任何有关我要找的内容的直接主题。我正在尝试创建一个Android应用程序，只需按一下按钮（我已经工作）拨出紧急号码，但无法获取显示的位置（显示在经度和纬度），我尝试用Toast和EditText框。我是Android开发的新手，所以想从容易开始，但LongLat部分很麻烦。任何帮助将不胜感激。

下面是我一直在篡改的代码，试图让它抓住Long和Lat，然后在另一个文件中我一直试图使用点击监听器将它分配给按钮，所以当按钮是按下（在main.xml中）它将在文本字段或吐司中显示Long和Lat。

import android.app.Activity;
import android.location.Location;
import android.location.LocationListener;
import android.os.Bundle;
import android.widget.TextView;
import android.content.Context;
import android.location.LocationManager;
import android.location.Criteria;



        public class EmergencyLocation extends Activity implements LocationListener {
            private TextView latituteField;
            private TextView longitudeField;
            private LocationManager locationManager;
            private String provider;

            /** Called when the activity is first created. **/
            @Override
            public void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.main);
                latituteField = (TextView) findViewById(R.id.TextView);
                longitudeField = (TextView) findViewById(R.id.long_lat);

                // Get the location manager
                locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
                // Define the criteria how to select the location provider -> use
                // default
                Criteria criteria = new Criteria();
                provider = locationManager.getBestProvider(criteria, false);
                Location location = locationManager.getLastKnownLocation(provider);

                // Initialise the location fields
                if (location != null) {
                    System.out.println("Provider " + provider + " has been selected.");
                    int lat = (int) (location.getLatitude());
                    int lng = (int) (location.getLongitude());
                    latituteField.setText(String.valueOf(lat));
                    longitudeField.setText(String.valueOf(lng));
                } else {
                    latituteField.setText("Provider not available");
                    longitudeField.setText("Provider not available");
                }
            }








        private void TextView() {
            // TODO Auto-generated method stub

        }


        @Override
        public void onLocationChanged(Location arg0) {
            // TODO Auto-generated method stub

        }


        @Override
        public void onProviderDisabled(String arg0) {
            // TODO Auto-generated method stub

        }


        @Override
        public void onProviderEnabled(String arg0) {
            // TODO Auto-generated method stub

        }


        @Override
        public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
            // TODO Auto-generated method stub

        }}

Answer 1

首先，您需要设置LocationManager：

LocationManager manager = (LocationManager) context.getSystemService(Context.LOCATION_SERVICE);

// set preferred provider based on the best accuracy possible
Criteria fineAccuracyCriteria = new Criteria();
fineAccuracyCriteria.setAccuracy(Criteria.ACCURACY_FINE);
String preferredProvider = manager.getBestProvider(fineAccuracyCriteria, true);

现在，您必须创建LocationListener。在这种情况下，它调用方法updateLocation()：

LocationListener listener = new LocationListener() {
        public void onLocationChanged(Location location) {
            // called when a new location is found by the network location provider.
            updateLocation(location);
        }

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

        public void onProviderEnabled(String provider) {}

        public void onProviderDisabled(String provider) {}
    };

修改

然后，您必须使用LocationManager注册侦听器（并尝试获取缓存位置）：

manager.requestLocationUpdates(preferredProvider, 0, 0, listener); // get a fast fix - cached version updateLocation(manager.getLastKnownLocation());

最后，updateLocation()方法：

private void updateLocation(Location location) { if (location == null) return; // save location details latitude = (float) location.getLatitude(); longitude = (float) location.getLongitude(); }

<强> EDIT2：

好的，只看到你的代码。为了使其工作，只需移动几位：

/** Called when the activity is first created. **/ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); latituteField = (TextView) findViewById(R.id.TextView); longitudeField = (TextView) findViewById(R.id.long_lat); // Get the location manager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); // Define the criteria how to select the location provider -> use // default Criteria criteria = new Criteria(); provider = locationManager.getBestProvider(criteria, false); locationManager.requestLocationUpdates(provider, 0, 0, this); Location location = locationManager.getLastKnownLocation(provider); onLocationChanged(location); } @Override protected void onDestroy() { super.onDestroy(); locationManager.removeUpdates(this); } @Override public void onLocationChanged(Location location) { if (location != null) { System.out.println("Provider " + provider + " has been selected."); int lat = (int) (location.getLatitude()); int lng = (int) (location.getLongitude()); latituteField.setText(String.valueOf(lat)); longitudeField.setText(String.valueOf(lng)); } else { latituteField.setText("Provider not available"); longitudeField.setText("Provider not available"); } }

希望它有所帮助！

Answer 2

非常简单。我使用 locationListener 作为 Location 类中的属性。我是这样做的：

package com.rifsoft.android.helper.location;

import com.rifsoft.android.helper.IListener;

import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;

public class Location implements IListener
{
  public final static int IDX_LATITIDE = 0;
  public final static int IDX_LONGITUDE = 1;

  private double[] lastLocation =  {0.0, 0.0};  
  private LocationManager locationManager = null;
  private ILocation activity = null;

  private LocationListener locationListener  = new LocationListener()
  {
      public void onLocationChanged(android.location.Location location) 
      {
        // TODO: http://developer.android.com/guide/topics/location/obtaining-user-location.html#BestEstimate
        lastLocation[IDX_LATITIDE] = location.getLatitude();
        lastLocation[IDX_LONGITUDE] = location.getLongitude();
        activity.onLocationChange();
      }

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

      public void onProviderEnabled(String provider) {}

      public void onProviderDisabled(String provider) {}
  };

  /**
   * Constructor, needs LocationManager
   * @param activity Activity that will receive the notification when location has changed
   * @param locationManager LocationManager
   */
  public Location(final ILocation act, LocationManager lm) throws LocationException
  {
    if (lm == null)
    {
      throw new LocationException(LocationException.ERR_NULL_LOCATION_MANAGER);
    }

    if (act == null)
    {
      throw new LocationException(LocationException.ERR_NULL_ILOCATION);
    }

    locationManager = lm;
    activity = act;

    registerListener();   

    android.location.Location lastCachedLocation = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
    if (lastCachedLocation != null)
    {
      lastLocation[IDX_LATITIDE] = lastCachedLocation.getLatitude();
      lastLocation[IDX_LONGITUDE] = lastCachedLocation.getLatitude();
    }
  }

  /**
   * Retuns last known most accurate location as latitude, longitude
   * @return Latitude, Longitude
   */
  public double[] getLastLocation()
  {
    return lastLocation;
  }

  @Override
  public void registerListener() 
  {   
    locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, locationListener);   
    locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, locationListener);   
  }

  @Override
  public void unRegisterListener() 
  {
    locationManager.removeUpdates(locationListener);    
  }
}

然后activity.onLocationChange（）就像

  public void onLocationChange() 
  {
    locationUpdated = true;

    double[] coordinates = location.getLastLocation();

    EditText lon = (EditText) activity.findViewById(R.id.longitude_value);
    lon.setText(String.valueOf(coordinates[Location.IDX_LONGITUDE]));

    EditText lat = (EditText) activity.findViewById(R.id.latitude_value);   
    lat.setText(String.valueOf(coordinates[Location.IDX_LATITIDE]));
  }

在Android文本框中打印经度和纬度

2 个答案: