package com.google.android;
import java.util.List;
import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapController;
import com.google.android.maps.MapView;
import com.google.android.maps.Overlay;
 
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Point;
import android.os.Bundle;
public class GoogleMap extends MapActivity {
 MapView mapView; 
    MapController mc;
    GeoPoint p;
    MapOverlay mapOverlay;
    Point screenPts;
    Bitmap bmp;
    List<Overlay> listOfOverlays;
    class MapOverlay extends com.google.android.maps.Overlay
    {
        @Override
        public boolean draw(Canvas canvas, MapView mapView, boolean shadow, long when) 
        {
            super.draw(canvas, mapView, shadow);                   
            //---translate the GeoPoint to screen pixels---
            screenPts = new Point();
            mapView.getProjection().toPixels(p, screenPts);
            //---add the marker---
            bmp = BitmapFactory.decodeResource(
                getResources(), R.drawable.icon);
            canvas.drawBitmap(bmp, screenPts.x, screenPts.y-50, null);         
            return true;
        }
    } 
    
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        //mc.animateTo(p);
        //mc.setZoom(17); 
        mapOverlay = new MapOverlay();
        listOfOverlays = mapView.getOverlays();
        listOfOverlays.clear();
        listOfOverlays.add(mapOverlay);        
        
        //mapView = (MapView)findViewById(R.id.map_view);
        mapView.invalidate();
    }
    protected boolean isRouteDisplayed(){
     return false;
    }
}


소스는 위와 같고, 이미 구글맵을 띄우는 테스트는 끝났습니다.
정상적으로 구글맵이 뜨는데 마커 추가하는 소스를 넣었더니 에러가 나네요.


02-10 09:14:03.598: ERROR/AndroidRuntime(829):     at dalvik.system.NativeStart.main(Native Method)
02-10 09:14:03.598: ERROR/AndroidRuntime(829): Caused by: java.lang.NullPointerException
02-10 09:14:03.598: ERROR/AndroidRuntime(829):     at com.google.android.GoogleMap.onCreate(GoogleMap.java:51)


이런 에러입니다.

널포인트 예외가 자꾸 발생하는데, 이유를 잘 모르겠네요.