Android GPS如何显示当前位置

Question

我在android开发方面经验不足，我想在地图上显示当前位置。 但这向我显示了另一个位置，该位置在加拿大。 这是我的代码：

package com.manita.mapuse;

import android.content.Context;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.view.View;
import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapController;

import com.google.android.maps.MapView;
public class MapuseActivity extends MapActivity implements LocationListener {
    private MapView  mapView = null;
    private MapController mc;
    private GeoPoint location;
    double lat;
    double lon;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

      //---use the LocationManager class to obtain GPS locations---
        LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);    

        LocationListener locationListener = new MyLocationListener();

        lm.requestLocationUpdates( LocationManager.GPS_PROVIDER,  0, 0, locationListener);

        }


    /* Class My Location Listener */

    public class MyLocationListener implements LocationListener

    {

    @Override

    public void onLocationChanged(Location loc)

    {

    loc.getLatitude();

    loc.getLongitude();

    lat= loc.getLatitude();

    lon= loc.getLongitude();
    }

    @Override

    public void onProviderDisabled(String provider)

    {

    }


    @Override

    public void onProviderEnabled(String provider)

    {
    }


    @Override

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

    {


    }

    } /*End of Class MyLocationListener */





    /*   class map view     */

    public MapView viewmap (View mapview, double latitude, double longitude){

        this.mapView =  new MapView(this,this.getResources().getString(R.string.mapKey));

        this.mapView.setClickable(true);

        this.mc = this.mapView.getController();

        this.location = new GeoPoint((int) (latitude * 1000000.0),(int) (longitude * 1000000.0));

        this.mc.setCenter(this.location);

        this.mc.setZoom(17);

        this.mapView.setSatellite(true);

        this.mapView.invalidate();

        this.setContentView(this.mapView);

        mapView.setBuiltInZoomControls(true);

        return mapView;

    }
     /* End class map view     */



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

    }



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

    }



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

    }



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

    }



    @Override
    protected boolean isRouteDisplayed() {
        // TODO Auto-generated method stub
        return false;
    }


}

Answer 1

我太困惑了，您需要对此进行很多更改，尝试从我的帖子中查看一些教程，您从那里获得了很多链接

如何在带有标记的android中显示地图

Answer 2

这里http://www.vogella.de/articles/AndroidLocationAPI/article.html#overview_maps是一个非常不错的示例。 只需复制粘贴即可。

Answer 3

这是全部代码吗？ 我看不到对您的mapview对象进行任何调用来更新纬度或经度。 也许尝试初始化mc控制器，并将这段代码添加到onLocationChanged方法中，看看会发生什么。 这只是为了帮助您找到问题，实际上不要留下这样的代码，因为如果您甚至不知道MapController是否已被初始化，则使用MapController是危险的。

@Override

public void onLocationChanged(Location loc)

{
  loc.getLatitude();
  loc.getLongitude();
  lat= loc.getLatitude();
  lon= loc.getLongitude();
  this.location = new GeoPoint((int) (latitude * 1000000.0),(int) (longitude * 1000000.0));
  this.mc.setCenter(this.location);
}