android overlay不可見

Question

我正在製作一個基於位置的應用程序。
我有以下代碼：

Drawable blueDrawable = getApplicationContext().getResources().getDrawable(R.drawable.blue); 
Drawable redDrawable = getApplicationContext().getResources().getDrawable(R.drawable.red); 
CustomizedOverlay blueItemizedOverlay = new CustomizedOverlay(blueDrawable); 
CustomizedOverlay redItemizedOverlay = new CustomizedOverlay(redDrawable); 

String [] s = startloc.getText().toString().split(" "); 
Log.e(tag, s[0]); Log.e(tag, s[1]); 
Double lat = Double.parseDouble(s[0]); 
Double lon = Double.parseDouble(s[1]); 
GeoPoint startpoint = new GeoPoint((int) (lat * 1e6) , (int) (lon * 1e6)); 

s = startloc.getText().toString().split(" "); 
lat = Double.parseDouble(s[0]); 
lon = Double.parseDouble(s[1]); 
GeoPoint stoppoint = new GeoPoint((int) (lat * 1e6) , (int) (lon * 1e6)); 

OverlayItem overlayitem = new OverlayItem(startpoint, "base camp",""); 
blueItemizedOverlay.addOverlay(overlayitem); 

地圖是動畫到正確的點。但疊加層沒有顯示出來。
如果你想要CustomizedOverlay類，我會發布它。
謝謝。

Answer 1

我忘了補充

List<Overlay> mapOverlays = mapView.getOverlays(); 
mapOverlays.add(blueItemizedOverlay);