Android MapView

Question

我想在Android中为myLocation添加覆盖图。地图显示，但覆盖图不显示。我确实使用扩展了ItemizedOverlay的单独类来显示叠加层。我想知道有没有办法显示这个单独的点，而不创建一个单独的类？

附件是活动类的源代码。

public class WalkAbout extends MapActivity { 

    //for Hello_mapview 
    List<Overlay> mapOverlays; 
    Drawable drawable; 

    private MapView m_vwMap; 
    private MapController m_mapController; 
    private PathOverlay m_pathOverlay; 
    private MyLocationOverlay m_locationOverlay; 

    private ArrayList<GeoPoint> m_arrPathPoints; 
    private ArrayList<OverlayItem> m_arrPicturePoints; 

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

     initLayout(); 
    } 
    @Override 
    protected boolean isRouteDisplayed() { 
     return false; 
    } 

    private void initLocationData() { 
     // TODO 
    } 

    private void initLayout() { 
     //instantiate XML File into corresponding view objects. 
     //Then inflate new view from XML resource. 
     setContentView(R.layout.map_layout); 
     MapView m_vwMap = (MapView)findViewById(R.id.mapview); 
     m_vwMap.setBuiltInZoomControls(true); 
     m_vwMap.setSatellite(true); 

     //retrieve list of overlay objects 
     mapOverlays=m_vwMap.getOverlays(); 

     //set market for overlays 
     drawable=this.getResources().getDrawable(R.drawable.item); 
     drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), 
            drawable.getIntrinsicHeight()); 

     //create OverlayItem with my location 
     m_locationOverlay= new MyLocationOverlay(this, m_vwMap); 

     //enable market to set location and direction 
     m_locationOverlay.enableCompass(); 
     m_locationOverlay.enableMyLocation(); 

     mapOverlays.add(m_locationOverlay); 
     } 
} 

Answer 1

您需要在您的m_vwMap上调用invalidate（），以便重绘自己。