BitmapDescriptorFactory.fromView(view)返回null，报异常

gometest

MarkerOptions options = new MarkerOptions();
BitmapDescriptor bd = BitmapDescriptorFactory
        .fromView(mapimgView);
options.draggable(false)
        .position(latlng)
        .snippet(" ")
        .icon(bd);
Marker marker = mAMap.addMarker(options);

已确定mapimgView不为null;

log:
W/System.err:     at android.view.ViewGroup.dispatchDraw(ViewGroup.java:4087)
        at android.view.View.buildDrawingCacheImpl(View.java:18559)
        at android.view.View.buildDrawingCache(View.java:18421)
        at android.view.View.getDrawingCache(View.java:18327)
        at android.view.View.getDrawingCache(View.java:18292)
        at com.amap.api.col.ct.a(Util.java:1238)
        at com.amap.api.maps.model.BitmapDescriptorFactory.fromView(BitmapDescriptorFactory.java:115)