android 9-patch image programmatically

private Drawable getThumb(int resId) {
Bitmap b = GBitmap.getResSoftBitmap(mContext, resId);
byte[] chunk = b.getNinePatchChunk();
NinePatchDrawable mapNinePatch = new NinePatchDrawable(getResources(),
b, chunk, new Rect(), null);
return mapNinePatch;
}